阅读说明：本技术 一种脉冲消融仪及其控制方法 (Pulse ablation instrument and control method thereof ) 是由 史世江 王坤 高国庆 王永胜 于 2020-11-30 设计创作，主要内容包括：本申请公开了一种脉冲消融仪及其控制方法。脉冲消融仪包括电源电路、脉冲开关电路、采样电路和开关控制电路。电源电路用于给负载供电。脉冲开关电路与电源电路连接,以调控电源电路向负载输出的电流。采样电路用于采样流经负载的供电回路的电流并得到采样值。开关控制电路分别与采样电路和脉冲开关电路电连接,用于根据采样值输出控制脉冲开关电路工作的驱动信号,并在采样值大于门限值的情况下,降低驱动信号的占空比,以降低电源电路的输出电流。本申请的脉冲消融仪及其控制方法能够在流经负载和负载的供电回路的电流过大时,降低流经负载和负载的供电回路的电流,达到保护负载和供电回路中的开关器件的效果,避免开关器件和负载受到损害。(The application discloses a pulse ablation instrument and a control method thereof. The pulse ablation instrument comprises a power circuit, a pulse switch circuit, a sampling circuit and a switch control circuit. The power circuit is used for supplying power to a load. The pulse switch circuit is connected with the power circuit to regulate and control the current output by the power circuit to the load. The sampling circuit is used for sampling the current flowing through the power supply loop of the load and obtaining a sampling value. The switch control circuit is respectively electrically connected with the sampling circuit and the pulse switch circuit and used for outputting a driving signal for controlling the pulse switch circuit to work according to the sampling value and reducing the duty ratio of the driving signal under the condition that the sampling value is larger than a threshold value so as to reduce the output current of the power supply circuit. The pulse ablation instrument and the control method thereof can reduce the current flowing through the load and the power supply loop of the load when the current flowing through the load and the power supply loop of the load is overlarge, achieve the effect of protecting the load and a switch device in the power supply loop, and avoid the switch device and the load from being damaged.)

1. A pulse ablator, comprising:

a power supply circuit for supplying power to a load;

the pulse switch circuit is connected with the power supply circuit to regulate and control the current output by the power supply circuit to the load;

the sampling circuit is used for sampling the current flowing through the power supply loop of the load and obtaining a sampling value;

and the switch control circuit is respectively electrically connected with the sampling circuit and the pulse switch circuit and is used for outputting a driving signal for controlling the pulse switch circuit to work according to the sampling value, and reducing the duty ratio of the driving signal under the condition that the sampling value is greater than a threshold value so as to reduce the output current of the power supply circuit.

2. The pulse ablator of claim 1, wherein said threshold values comprise a first threshold value and a second threshold value:

under the condition that the sampling value is larger than the first threshold value, the switch control circuit reduces the duty ratio of the driving signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value; and/or

And under the condition that the sampling value is larger than the second threshold value, the switch control circuit reduces the duty ratio of the driving signal cycle by cycle until the pulse switch circuit stops working, wherein the second threshold value is larger than the first threshold value.

3. The pulse ablator of claim 2, wherein said switch control circuit comprises:

the pulse regulation and control circuit is used for generating a pulse signal and regulating the duty ratio of the pulse signal according to the sampling value;

the driving circuit is used for receiving the pulse signal and outputting the driving signal according to the pulse signal, and the duty ratio of the driving signal is changed along with the change of the duty ratio of the pulse signal.

4. The pulse ablator of claim 3, wherein the pulse conditioning circuit comprises:

a first pulse generator for generating a pulse signal;

and the first pulse width adjusting circuit is electrically connected with the first pulse generator, the sampling circuit and the driving circuit and is used for receiving the pulse signal and adjusting the duty ratio of the pulse signal according to the sampling value.

5. The pulse ablator of claim 4, wherein the first pulse width modulation circuit comprises:

and the pulse regulation and control first sub-circuit is used for judging whether the sampling value is larger than the first threshold value or not according to the input sampling value, and reducing the duty ratio of the pulse signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value under the condition that the sampling value is larger than the first threshold value.

6. The pulse ablator of claim 4, wherein the first pulse width modulation circuit comprises:

the non-inverting input end of the comparator is connected with the sampling value, the inverting input end of the comparator is connected with the second threshold value, and the comparator outputs a trigger level under the condition that the sampling value is larger than the second threshold value;

the trigger is used for receiving the trigger level and continuously outputting a control signal;

and the pulse regulation and control second sub-circuit is used for reducing the duty ratio of the pulse signal cycle by cycle according to the control signal until the duty ratio of the pulse signal is reduced to zero.

7. The pulse ablatograph of claim 6, further comprising a main control unit, wherein the main control unit controls an alarm unit to alarm when the sampling value is greater than the second threshold value; the main control unit is also used for sending a reset signal to the trigger according to an external reset instruction so as to reset the trigger and stop outputting the control signal.

8. The pulse ablator of claim 3, wherein the pulse conditioning circuit comprises:

the second pulse width regulating circuit is electrically connected with the sampling circuit and is used for generating a duty ratio regulating and controlling signal according to the sampling value;

and the second pulse generator is electrically connected with the second pulse width regulating circuit and the driving circuit and used for generating a pulse signal according to the duty ratio regulating and controlling signal, and the duty ratio of the pulse signal is regulated by the duty ratio regulating and controlling signal.

9. The pulse ablator of claim 3, wherein said power circuit comprises a first direct current power source; the pulse switching circuit includes a first pulse switching device;

the first end of the first pulse switch device is connected with the anode of the first direct current power supply, the second end of the first pulse switch device is connected with the first end of the load, the second end of the load is connected with the cathode of the first direct current power supply, and the control end of the first pulse switch device is connected with the output end of the driving circuit.

10. The pulse ablatograph of claim 9, wherein said power circuit further comprises a second dc power source, a positive pole of said second dc power source connected to said second end of said load and a negative pole of said first dc power source;

the pulse switching circuit further comprises a second pulse switching device, a first end of the second pulse switching device is connected with a first end of the load, a second end of the second pulse switching device is connected with a negative electrode of the second direct-current power supply, and a control end of the second pulse switching device is connected with the driving circuit;

the pulse regulation and control circuit is used for generating a first pulse signal and a second pulse signal, and the driving circuit comprises a first driving circuit and a second driving circuit;

the output end of the first driving circuit is connected with the control end of the first pulse switching device, and the first driving circuit is used for receiving the first pulse signal and outputting a first driving signal to drive the first pulse switching device to work;

the output end of the second driving circuit is connected with the control end of the second pulse switching device, and the second driving circuit is used for receiving the second pulse signal and outputting a second driving signal to drive the second pulse switching device to work.

11. The pulse ablator of claim 10, wherein:

the first pulse switch device and the second pulse switch device are both IGBT transistors; or

The first pulse switch device and the second pulse switch device are both MOS transistors.

12. The pulse ablator according to any one of claims 1 to 11, wherein the sampling circuitry comprises one or more current transformers comprising a primary winding and a secondary winding; the primary side winding is connected in series in the power supply loop of the load, the secondary side winding is electrically connected with the switch control circuit, and the secondary side winding is used for outputting the sampling value.

13. The pulse ablatograph of claim 12, wherein the sampling circuit further comprises a voltage divider circuit, the voltage divider circuit comprising a first resistor and a second resistor connected in series between an output terminal of a secondary winding of the current transformer and a ground terminal, a connection terminal of the first resistor and the second resistor outputting the sampled value.

14. A method of controlling a pulse ablator, comprising:

sampling current flowing through a power supply loop of a load and obtaining a sampling value;

and when the sampling value is larger than the threshold value, reducing the duty ratio of a driving signal for controlling the pulse switching circuit to work so as to reduce the current output to the load.

15. The pulse ablator control method of claim 14, wherein said threshold values comprise a first threshold value and a second threshold value, and wherein said reducing a duty cycle of a drive signal that controls operation of a pulse switching circuit if said sampled value is greater than said threshold value comprises:

under the condition that the sampling value is larger than the first threshold value, reducing the duty ratio of the driving signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value; and/or

And under the condition that the sampling value is larger than the second threshold value, reducing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops working, wherein the second threshold value is larger than the first threshold value.

Technical Field

The application relates to the technical field of pulse ablation equipment, in particular to a pulse ablation instrument and a control method thereof.

Background

The pulse ablation instrument can convert commercial power into high-voltage direct current through module circuits such as rectification, inversion and boosting, then outputs steep pulses through a pulse output circuit, and achieves the purpose of ablation on biological tissues by utilizing an electroporation technology. However, when the switching device of the pulse output circuit is operated under a high-voltage high-current operating condition and a load is short-circuited or a load current is too large, the switching device is easily subjected to high-current impact and is damaged.

Disclosure of Invention

The application aims to provide a pulse ablation instrument and a control method thereof, which aim to solve the technical problems in the prior art: how to avoid the switch device from being damaged due to the impact of large current when the load is short-circuited or the load current is overlarge.

In order to solve the technical problem, the following technical scheme is adopted in the application:

the embodiment of the application provides a pulse ablation instrument, the pulse ablation instrument includes: a power supply circuit for supplying power to a load; the pulse switch circuit is connected with the power supply circuit to regulate and control the current output by the power supply circuit to the load; the sampling circuit is used for sampling the current flowing through the power supply loop of the load and obtaining a sampling value; and the switch control circuit is respectively electrically connected with the sampling circuit and the pulse switch circuit and is used for outputting a driving signal for controlling the pulse switch circuit to work according to the sampling value, and reducing the duty ratio of the driving signal under the condition that the sampling value is greater than a threshold value so as to reduce the output current of the power supply circuit.

In some embodiments, the threshold value includes a first threshold value, and in the case where the sampling value is greater than the first threshold value, the switch control circuit decreases the duty cycle of the driving signal cycle by cycle until the sampling value is less than or equal to the first threshold value.

In some embodiments, the threshold value includes a second threshold value, and in the case where the sampled value is greater than the second threshold value, the switching control circuit decreases the duty cycle of the driving signal cycle by cycle until the pulse switching circuit stops operating.

In some embodiments, the threshold value includes a first threshold value and a second threshold value, and in the case where the sampling value is greater than the first threshold value, the switch control circuit decreases the duty cycle of the driving signal cycle by cycle until the sampling value is less than or equal to the first threshold value; and under the condition that the sampling value is larger than the second threshold value, the switch control circuit reduces the duty ratio of the driving signal cycle by cycle until the pulse switch circuit stops working, wherein the second threshold value is larger than the first threshold value.

In some embodiments, the switch control circuit comprises: the pulse regulation and control circuit is used for generating a pulse signal and regulating the duty ratio of the pulse signal according to the sampling value; the driving circuit is used for receiving the pulse signal and outputting the driving signal according to the pulse signal, and the duty ratio of the driving signal is changed along with the change of the duty ratio of the pulse signal.

In some embodiments, the pulse regulation circuitry comprises: a first pulse generator for generating a pulse signal; and the first pulse width adjusting circuit is electrically connected with the first pulse generator, the sampling circuit and the driving circuit and is used for receiving the pulse signal and adjusting the duty ratio of the pulse signal according to the sampling value.

In some embodiments, the first pulse width modulation circuit comprises: and the pulse regulation and control first sub-circuit is used for judging whether the sampling value is larger than the first threshold value or not according to the input sampling value, and reducing the duty ratio of the pulse signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value under the condition that the sampling value is larger than the first threshold value.

In some embodiments, the first pulse width modulation circuit further comprises: the non-inverting input end of the comparator is connected with the sampling value, the inverting input end of the comparator is connected with the second threshold value, and the comparator outputs a trigger level under the condition that the sampling value is larger than the second threshold value; the trigger is used for receiving the trigger level and continuously outputting a control signal; and the pulse regulation and control second sub-circuit is used for reducing the duty ratio of the pulse signal cycle by cycle according to the control signal until the duty ratio of the pulse signal is reduced to zero.

In some embodiments, the pulse ablatograph further comprises a main control unit, and the main control unit controls an alarm unit to alarm when the sampling value is larger than the second threshold value; the main control unit is also used for sending a reset signal to the trigger according to an external reset instruction so as to reset the trigger and stop outputting the control signal.

In some embodiments, the pulse regulation circuitry comprises: the second pulse width regulating circuit is electrically connected with the sampling circuit and is used for generating a duty ratio regulating and controlling signal according to the sampling value; and the second pulse generator is electrically connected with the second pulse width regulating circuit and the driving circuit and used for generating a pulse signal according to the duty ratio regulating and controlling signal, and the duty ratio of the pulse signal is regulated by the duty ratio regulating and controlling signal.

In some embodiments, the power circuit includes a first direct current power supply; the pulse switching circuit includes a first pulse switching device; the first end of the first pulse switch device is connected with the anode of the first direct current power supply, the second end of the first pulse switch device is connected with the first end of the load, the second end of the load is connected with the cathode of the first direct current power supply, and the control end of the first pulse switch device is connected with the output end of the driving circuit.

In some embodiments, the power circuit further comprises a second dc power source, the positive pole of the second dc power source being connected to the second end of the load and the negative pole of the first dc power source; the pulse switching circuit further comprises a second pulse switching device, a first end of the second pulse switching device is connected with a first end of the load, a second end of the second pulse switching device is connected with a negative electrode of the second direct-current power supply, and a control end of the second pulse switching device is connected with the driving circuit; the pulse regulation and control circuit is used for generating a first pulse signal and a second pulse signal, and the driving circuit comprises a first driving circuit and a second driving circuit; the output end of the first driving circuit is connected with the control end of the first pulse switching device, and the first driving circuit is used for receiving the first pulse signal and outputting a first driving signal to drive the first pulse switching device to work; the output end of the second driving circuit is connected with the control end of the second pulse switching device, and the second driving circuit is used for receiving the second pulse signal and outputting a second driving signal to drive the second pulse switching device to work.

In some embodiments, the first pulse switching device and the second pulse switching device are both IGBT transistors.

In some embodiments, the first pulse switching device and the second pulse switching device are both MOS transistors.

In some embodiments, the sampling circuit includes one or more current transformers including a primary winding and a secondary winding; the primary side winding is connected in series in the power supply loop of the load, the secondary side winding is electrically connected with the switch control circuit, and the secondary side winding is used for outputting the sampling value.

In some embodiments, the sampling circuit further includes a voltage divider circuit including a first resistor and a second resistor connected in series between an output terminal of the secondary winding of the current transformer and a ground terminal, and a connection terminal of the first resistor and the second resistor outputs the sampling value.

The embodiment of the present application further provides a control method of a pulse ablation instrument, including: sampling current flowing through a power supply loop of a load and obtaining a sampling value; and when the sampling value is larger than the threshold value, reducing the duty ratio of a driving signal for controlling the pulse switching circuit to work so as to reduce the current output to the load.

In some embodiments, the threshold value comprises a first threshold value, and the reducing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit in the case that the sampling value is greater than the threshold value comprises: and under the condition that the sampling value is larger than the first threshold value, reducing the duty ratio of the driving signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value.

In some embodiments, the threshold value comprises a second threshold value, and the reducing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit in the case that the sampled value is greater than the threshold value comprises: and under the condition that the sampling value is larger than the second threshold value, reducing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops working.

In some embodiments, the threshold value comprises a first threshold value and a second threshold value, and the reducing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit when the sampling value is greater than the threshold value comprises: under the condition that the sampling value is larger than the first threshold value, reducing the duty ratio of the driving signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value; and under the condition that the sampling value is larger than the second threshold value, reducing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops working, wherein the second threshold value is larger than the first threshold value.

According to the technical scheme, the method has at least the following advantages and positive effects:

the pulse ablation instrument and the control method thereof in the embodiment of the application obtain the sampling value by setting the sampling circuit to sample the current flowing through the load and the power supply loop of the load, and reduce the duty ratio of the pulse signal to reduce the output current of the power supply circuit when the sampling value is larger than the threshold value, so that the current flowing through the load and the power supply loop of the load can be reduced in real time when the current flowing through the load and the power supply loop of the load is overlarge, the effect of protecting the switching device of the pulse switching circuit in the power supply loop of the load is achieved, and the switching device of the pulse switching circuit is prevented from being damaged due to continuous large-current impact. In addition, the pulse ablation instrument and the control method thereof can also prevent the load from being under large current for a long time, so that damage to the load can be avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic electrical circuit diagram of a pulse ablator according to one embodiment of the present application;

FIG. 2 is a schematic electrical circuit diagram of a pulse ablator according to one embodiment of the present application;

FIG. 3 is a circuit diagram of a pulse ablator according to an embodiment of the present application;

FIG. 4 is a graph illustrating the variation of the pulse waveform and the sampling value waveform over time according to an embodiment of the present disclosure;

FIG. 5 is a schematic electrical circuit diagram of a pulse ablator according to another embodiment of the present application;

FIG. 6 is a schematic flow chart of a method of controlling a pulse ablator according to one embodiment of the present application;

FIG. 7 is a schematic flow chart of a method for controlling a pulse ablator according to an embodiment of the present application;

FIG. 8 is a schematic flow chart of a method of controlling a pulse ablator according to one embodiment of the present application;

FIG. 9 is a schematic flow chart diagram of a method of controlling a pulse ablator according to another embodiment of the present application;

fig. 10 is a schematic flow chart of a control method of a pulse ablator according to yet another embodiment of the present application.

The reference numerals are explained below:

100. a pulse ablation instrument;

1. a power supply circuit; 11. A first direct current power supply;

12. a second direct current power supply;

2. a pulse switching circuit;

21. a first pulse switching device; 211. A first terminal of a first pulse switching device;

212. a second terminal of the first pulse switching device; 213. A control terminal of the first pulse switching device;

22. a second pulse switching device; 221. A first terminal of a second pulse switching device;

222. a second terminal of the second pulse switching device; 223. A control terminal of the second pulse switching device;

3. a sampling circuit; 31. A current transformer;

311. a primary side winding; 312. A secondary side winding;

33. a voltage dividing circuit;

331. a first resistor; 332. A second resistor;

4. a switch control circuit;

41. a pulse regulation circuit;

411. a first pulse generator;

412. a first pulse width adjusting circuit; 4121. A pulse-modulated first sub-circuit;

4122. a comparator; 4123. A trigger;

4124. a pulse-controlled second sub-circuit;

413. a second pulse width adjusting circuit;

414. a second pulse generator;

43. a drive circuit;

431. a first drive circuit; 4311. A first drive circuit output;

432. a second drive circuit; 4321. A second drive circuit output;

5. a main control unit;

6. an alarm unit;

101. a load;

1011. a first end of a load; 1012. A second end of the load;

102. and a power supply loop.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The terms "first", "second" and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", "third" may explicitly or implicitly include one or more of the features. In the description of the present application, "a plurality" means two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "communicate", "mount", "connect", and the like are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In the related art, the pulse ablation instrument is connected with a protection resistor in series in a power supply loop of a load to protect an internal circuit and the load of the pulse ablation instrument. However, this solution has the following drawbacks: when the load impedance of the pulse ablation instrument is low, the protection resistor connected in series in the pulse output circuit can divide the output pulse voltage, so that the difference between the pulse voltage value on the load and the direct-current high voltage is large, the pulse voltage level required by the electroporation technology cannot be reached, and the ablation effect is reduced. How to avoid the switch device of the internal circuit of the pulse ablation instrument and the like from being damaged due to continuous large current impact and simultaneously not reduce the output voltage at two ends of the load is also a problem to be solved.

Referring to fig. 1, a pulse ablatograph 100 according to an embodiment of the present application includes a power circuit 1, a pulse switch circuit 2, a sampling circuit 3, and a switch control circuit 4.

Wherein the power supply circuit 1 is used to supply a load 101. The pulse switch circuit 2 is connected to the power supply circuit 1 to regulate the current output from the power supply circuit 1 to the load 101. The sampling circuit 3 is used for sampling the current flowing through the power supply loop 102 of the load and obtaining a sampling value. The switch control circuit 4 is respectively electrically connected with the sampling circuit 3 and the pulse switch circuit 2, and is used for outputting a driving signal for controlling the pulse switch circuit 2 to work according to the sampling value, and reducing the duty ratio of the driving signal under the condition that the sampling value is greater than a threshold value, so as to reduce the output current of the power circuit 1.

The pulse ablation instrument of the embodiment of the application obtains the sampling value by setting the sampling circuit to sample the current flowing through the load and the power supply loop of the load, and when the sampling value is larger than the threshold value, the duty ratio of the pulse signal is reduced through the switch control circuit so as to reduce the output current of the power supply circuit, so that when the current flowing through the load and the power supply loop of the load is overlarge, the current flowing through the load and the pulse switch device is reduced in real time, the effect of protecting the switch device in the pulse switch circuit is achieved, and the switch device is prevented from being damaged due to continuous large-current impact. In addition, the pulse ablation instrument and the control method thereof can also prevent the load from being under large current for a long time, so that damage to the load can be avoided.

The pulse ablation instrument controls the power supply circuit 1 to directly supply power to the load through the pulse switch circuit 2, so that the situation that the pulse voltage value on the load is greatly different from the direct-current high voltage due to the fact that the existing protective resistor connected in series in the power supply circuit divides the output pulse voltage can be avoided, and the ablation effect can be improved.

The following is further described with reference to the accompanying drawings.

Referring to fig. 2 and 3, the pulse ablatograph 100 includes a power circuit 1, a pulse switch circuit 2, a sampling circuit 3, and a switch control circuit 4. The power supply circuit 1 is used to supply power to a load. The load may be biological tissue or the like. The power supply circuit 1 includes a direct current power supply. The direct current power supply can be formed by storing direct current output by commercial power through an inverter circuit and a rectifying and filtering circuit in an energy storage capacitor. The power circuit may be comprised of one or more high voltage dc power supplies and may output high voltage pulses to a load. The voltage of the high-voltage pulse reaches the pulse voltage level required by the electroporation technology, and a better ablation effect can be realized. The high-voltage direct-current power supply in the power supply circuit can output 500V-4000V high-voltage power, for example, the high-voltage direct-current power supply can be used for outputting 500V, 1000V, 2500V, 3000V and 4000V high-voltage power, different output voltages of the high-voltage direct-current power supply are selected according to different load types, the ablation effect can be improved, and the protection of the load and an internal circuit of the pulse ablation instrument is facilitated. The pulse switch circuit 2 is connected to the power supply circuit 1 to regulate and control the current output from the power supply circuit 1 to the load 101. The power supply circuit 1 and the pulse switch circuit 2 constitute a power supply loop 102 of the load 101.

In some embodiments, the power supply circuit 1 and the pulse switch circuit 2 are configured to output a pulse current of a single polarity to a load. The power supply circuit 1 includes a first direct-current power supply 11; the pulse switching circuit 2 includes a first pulse switching device 21. The first end 211 of the first pulse switching device 21 is connected to the positive electrode of the first dc power supply 11, the second end 212 of the first pulse switching device 21 is connected to the first end 1011 of the load 101, the second end 1012 of the load 101 is connected to the negative electrode of the first dc power supply 11, the control end 213 of the first pulse switching device 21 is connected to the output end of the driving circuit 43, and specifically, the control end 213 of the first pulse switching device 21 is connected to the output end 4311 of the first driving circuit 431. The first drive signal output by the first drive circuit 431 controls the on/off of the first pulse switching device 21 so that the power supply circuit 1 outputs a unipolar pulse to the load. Therefore, the pulse ablator 100 can output unipolar pulse current to a load, and the circuit structure is simple, which is beneficial to improving the stability of the circuit operation of the pulse ablator 100.

In other embodiments, the power circuit 1 and the pulse switch circuit 2 are used to output bipolar pulse current to the load 101. The power supply circuit 1 includes a first direct-current power supply 11 and a second direct-current power supply 12; the pulse switching circuit 2 includes a first pulse switching device 21 and a second pulse switching device 22. The first end 211 of the first pulse switching device 21 is connected to the positive electrode of the first dc power supply 11, the second end 212 of the first pulse switching device 21 is connected to the first end 1011 of the load 101, the second end 1012 of the load 101 is connected to the negative electrode of the first dc power supply 11, and the control end 213 of the first pulse switching device 21 is connected to the output end 4311 of the first driving circuit 431. The positive electrode of the second dc power supply 12 is connected to the second end 1012 of the load 101 and the negative electrode of the first dc power supply 11, the first end 221 of the second pulse switching device 22 is connected to the first end 1011 of the load 101, the second end 222 of the second pulse switching device 22 is connected to the negative electrode of the second dc power supply 12, the control end 223 of the second pulse switching device 22 is connected to the driving circuit 43, and specifically, the control end 223 of the second pulse switching device 22 is connected to the output end 4321 of the second driving circuit 432. The first driving signal output by the first driving circuit 431 controls the on/off of the first pulse switching device 21, and the second driving signal output by the second driving circuit 432 controls the on/off of the second pulse switching device 22, so that the first pulse switching device 21 and the second pulse switching device 22 are alternately turned on and alternately turned off, and the power supply circuit 1 is caused to output a bipolar pulse to the load. Thus, the pulse ablator 100 can output a bipolar pulsed current to the load. The bipolar pulse current ablation provided by the embodiment can enable the electric field distribution to be more uniform, so that the problem of muscle contraction caused in the process of using the pulse ablation instrument can be reduced, the pulse ablation instrument can have a better ablation effect, and meanwhile, the safety of the ablation process of biological tissues can be improved.

Specifically, the first pulse switching device 21 and the second pulse switching device 22 are both IGBT transistors. Further, the first pulse switching device 21 and the second pulse switching device 22 are IGBT transistors of withstand voltage 1200V and current 30A. Alternatively, the first pulse switching device 21 and the second pulse switching device 22 are both MOS transistors. Thus, the driving signal can drive the first pulse switching device 21 through the control terminal 213 of the first pulse switching device 21 and drive the second pulse switching device 22 through the control terminal 223 of the second pulse switching device 22 to control the current flowing through the load 101 and the pulse switching device 2.

Referring to fig. 2 and 3, the sampling circuit 3 is used for sampling the current flowing through the power supply circuit 102 of the load 101 and obtaining a sampling value.

The sampling circuit 3 comprises one or more current transformers 31. The current transformer 31 may include, but is not limited to, a transformation ratio of 1: 50. the current transformers with the transformation ratios of 1:80, 1:100 or 1:200 and the like can ensure that the sampling value obtained by induction cannot be too high under the condition that the sampling current is large, namely the current flowing through the power supply loop 102 of the load 101, are favorable for preventing the sampling circuit from being damaged when the sampling current is too large, and are favorable for maintaining the stable operation of the circuit of the pulse ablation instrument. The current transformer 31 includes a primary winding 311 and a secondary winding 312; the primary winding 311 is connected in series to the power supply circuit 102 of the load 101, the secondary winding 312 is electrically connected to the switch control circuit 4, and the secondary winding 312 is used to output a sampling value. The current transformer 31 samples the current of the power supply circuit 102 of the load 101, so that a high-voltage circuit on the load side can be effectively isolated from a lower-voltage circuit on the sampling circuit side, and the high-voltage circuit on the load side is prevented from damaging the sampling circuit 3.

Further, the sampling circuit 3 further includes a voltage dividing circuit 33, the voltage dividing circuit 33 includes a first resistor 331 and a second resistor 332 connected in series between the output terminal of the secondary winding 312 of the current transformer 31 and the ground terminal, and the connection terminal of the first resistor 331 and the second resistor 332 outputs the sampling value. When the sampling circuit 3 includes a plurality of current transformers 31, the sampling circuit 3 may include voltage dividing circuits 33 corresponding to the plurality of current transformers 31. For example, as shown in the embodiment of fig. 3, the sampling circuit 3 includes two current transformers 31 and a voltage dividing circuit 33 corresponding to each current transformer 31. The current transformer L1 corresponds to the voltage dividing circuit 33 composed of a first resistor R7 and a second resistor R6; the current transformer L2 corresponds to the voltage dividing circuit 33 composed of the first resistor R13 and the second resistor R12. Compare in direct with the induced voltage that current transformer 31 inducted and obtain as the sampling value, after bleeder circuit 33 divides the induced voltage that current transformer 31 inducted and obtain, regard the voltage value of the sampling value of the output of the link of first resistance 331 and second resistance 332 as the sampling value again, be favorable to reducing the voltage of the sampling value of sampling circuit output to be favorable to protecting the internal circuit of pulse ablation instrument.

Referring to fig. 3, the sampling value output by the sampling circuit 3 may be further output to the switch control circuit 4 through the current limiting resistor, so that an excessive current can be prevented from flowing into the switch control circuit 4, which is beneficial to protecting the internal circuit of the switch control circuit 4. Specifically, the sampled value output from the sampling circuit 3 is output to the switch control circuit 4 through the current limiting resistors R8 and R11, and the sampled value output from the sampling circuit 3 is output to the switch control circuit 4 through the current limiting resistors R7 and R15.

The switch control circuit 4 is respectively electrically connected with the sampling circuit 3 and the pulse switch circuit 2, and is used for outputting a driving signal for controlling the pulse switch circuit 2 to work according to the sampling value, and reducing the duty ratio of the driving signal to reduce the output current of the power circuit under the condition that the sampling value is greater than a threshold value, so that the effect of protecting the pulse switch circuit 2 is achieved, and the pulse switch circuit 2 can be prevented from being damaged by overlarge current; meanwhile, the load can be prevented from being under a large current for a long time, so that damage to the load can be avoided.

In some embodiments, the threshold value comprises a first threshold value, which may correspond to a threshold value that the sample value exceeds when the load current is excessive. In the case where the sampling value is larger than the first threshold value, the switch control circuit 4 decreases the duty ratio of the drive signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value. Therefore, the switch control circuit 4 reduces the current flowing through the load and the pulse switch circuit when the current flowing through the load and the pulse switch circuit is too large, namely, reduces the output current of the power supply circuit until the current flowing through the load and the pulse switch circuit returns to normal, and realizes the over-current protection of the circuit where the load and the pulse switch circuit are located, namely the over-current protection of the power supply circuit of the load.

In some embodiments, the threshold value comprises a second threshold value, the second threshold value being greater than the first threshold value, the second threshold value may correspond to a threshold value that the sample value exceeds when the load is shorted. When the sampling value is larger than the second threshold value, the switching control circuit 4 decreases the duty ratio of the drive signal cycle by cycle until the pulse switching circuit stops operating. Therefore, the switch control circuit 4 reduces the duty ratio of the driving signal periodically until the pulse switch circuit stops working when the load is in short circuit, so that the output current of the power supply circuit can be gradually reduced, the pulse switch device is closed in a soft landing mode, the induced voltage spike caused by large current transient change can be avoided, the circuit safety in the process of closing the pulse switch circuit when the load is in short circuit can be improved, the short circuit protection of the load and the circuit where the pulse switch circuit is located is realized, and the short circuit protection of the power supply loop of the load is also realized.

In some embodiments, the threshold value comprises a first threshold value and a second threshold value. In the case where the sampling value is larger than the first threshold value, the switch control circuit 4 decreases the duty ratio of the drive signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value. And under the condition that the sampling value is greater than a second threshold value, the switch control circuit 4 reduces the duty ratio of the driving signal cycle by cycle until the pulse switch circuit stops working, wherein the second threshold value is greater than the first threshold value. In a specific example, the first threshold value can be modified and adjusted according to actual conditions, and can include, but is not limited to, values between 430mV and 550mV, such as values of 430mV, 440mV, 450mV, 460mV, 470mV, 480mV, 490mV, 500mV, 510mV, 520mV, 530mV, 540mV, 550 mV. The second threshold value can be modified and adjusted according to actual conditions, and can include, but is not limited to, values between 1.0V and 2.0V, such as 1.0V, 1.1V, 1.2V, 1.3V, 1.4V, 1.5V, 1.6V, 1.7V, 1.8V, 1.9V, 2.0V, and the like. Therefore, the switch control circuit 4 can simultaneously realize overcurrent protection and short-circuit protection of the circuit where the load and the pulse switch circuit are located, and the second threshold value is larger than the first threshold value, so that the first threshold value which is required to be reached by the sampling value when overcurrent protection is triggered and the second threshold value which is required to be reached by the sampling value when short-circuit protection is triggered can be distinguished, and thus, the overcurrent protection and the short-circuit protection of the circuit where the load and the pulse switch circuit are located can be simultaneously realized by the same control logic.

Specifically, with continued reference to fig. 2 and 3, the switch control circuit 4 includes a pulse control circuit 41 and a driving circuit 43. The pulse regulation and control circuit 41 is used for generating a pulse signal and regulating the duty ratio of the pulse signal according to a sampling value. The driving circuit 43 is configured to receive the pulse signal and output a driving signal according to the pulse signal, wherein a duty ratio of the driving signal changes with a change of the duty ratio of the pulse signal.

The pulse control circuit 41 is configured to generate a first pulse signal and a second pulse signal. The first pulse signal and the second pulse signal may be a pair of pulse signals having the same frequency and duty ratio and being 180 degrees out of phase.

The driving circuit 43 includes a first driving circuit 431 and a second driving circuit 432.

The output end 4311 of the first driving circuit 431 is connected to the control end 213 of the first pulse switching device 21, and the first driving circuit is configured to receive the first pulse signal and output the first driving signal to drive the first pulse switching device 21 to operate.

The output end 4321 of the second driving circuit 432 is connected to the control end 223 of the second pulse switch device 22, and the second driving circuit 432 is configured to receive the second pulse signal and output the second driving signal to drive the second pulse switch device 22 to operate.

In some embodiments, referring to fig. 3, the pulse control circuit 41 includes a first pulse generator 411 and a first pulse width modulation circuit 412. The first pulse generator 411 is used to generate a pulse signal, and specifically, the first pulse generator 411 may be used to output a pulse signal with a fixed duty ratio. When the power supply circuit 1 and the pulse switch circuit 2 are used to output a pulse current of a single polarity to a load, the first pulse generator 411 may generate a pulse signal with a fixed duty ratio. When the power circuit 1 and the pulse switch circuit 2 are used to output bipolar pulse current to the load 101, the first pulse generator 411 may be a complementary symmetric PWM waveform generator, and can simultaneously generate and output a pair of pulse signals with the same frequency and duty ratio and 180 degrees phase difference. The first pulse width adjusting circuit 412 is electrically connected to the first pulse generator 411, the sampling circuit 3 and the driving circuit 43, and is configured to receive the pulse signal and adjust the duty ratio of the pulse signal according to the sampled value. The first pulse width modulation circuit 412 includes a pulse conditioning first sub-circuit 4121. As shown in fig. 3, the pulse-controlled first sub-circuit 4121, that is, the pulse-controlled first sub-circuit U3 and the pulse-controlled first sub-circuit U5 shown in fig. 3, receive a sampling value through a CIN pin, and determine whether the sampling value is greater than a first threshold value according to the input sampling value, where the first threshold value may be modified and adjusted according to actual conditions, and the application range is wider.

The pulse control first sub-circuit 4121 decreases the duty ratio of the pulse signal cycle by cycle until the sample value is less than or equal to the first threshold value, when the sample value is greater than the first threshold value. That is to say, under the condition that the sampling value received by the CIN pin of the pulse regulation first sub-circuit 4121 is greater than the first threshold value, the pulse regulation first sub-circuit 4121 reduces the duty ratio of the pulse signal and outputs the pulse signal after the duty ratio is reduced, and when the next period of the pulse signal comes, if the sampling value received by the CIN pin is still greater than the first threshold value, the duty ratio of the current period of the pulse signal is continuously reduced and the pulse signal is output until the sampling value received by the CIN pin is less than or equal to the first threshold value. The pulse-width-by-pulse regulation circuit can be integrated in the pulse regulation and control first sub-circuit, and the duty ratio of the pulse signal can be reduced cycle by cycle. In some embodiments, reducing the duty cycle of the output pulse signal cycle by cycle may include, but is not limited to, reducing in two ways: (1) if the original duty ratio is 30%, decreasing by 29%, 28%, 27% and 26% according to the duty ratio; (2) the duty cycle is reduced in proportion to the duty cycle, e.g., 30% duty cycle, and each cycle is multiplied by a factor less than 1, e.g., 30% 0.9, 0.9. Therefore, the switch control circuit 4 can realize the overcurrent protection of the load and the circuit where the pulse switch circuit is located through the first pulse width adjusting circuit 412.

Referring to fig. 4, a section a of fig. 4 shows that the current of the power supply circuit 102 of the load 101 is in a normal range (i.e., V)_CINIs smaller than a first threshold value V_CINTH+The same as described later) of the first pulse generator 411 is generated₁The first pulse width adjustment circuit 412 adjusts the duty ratio of the pulse signal V1 according to the sampling value, and outputs the pulse signal V₂And a signal V received by a CIN pin of the pulse regulation first sub-circuit U3 or a pulse regulation first sub-circuit U5_CIN，V_CINI.e. a signal whose sample values vary with time. Wherein, V_CINTH+Is a first threshold value. In the region a, when the current of the power supply circuit 102 of the load 101 is in the normal range, the first pulse width modulation circuit 412 outputs the duty ratio and the pulse signal V₁Pulse signal V keeping consistency₂. The current of the supply circuit 102 of the load 101 is over-current (i.e. the signal V received by the first sub-circuit is pulsed)_CINReaching or exceeding a first threshold value V_CINTH+The same as described later), the pulse-controlled first sub-circuit 4121 decreases the duty ratio of the output pulse signal V2 cycle by cycle until V_CINIs smaller than a first threshold value V_CINTH+Then, the output pulse signal V is maintained₂The current duty cycle is unchanged until the over-current condition disappears or the pulse ablator resets. As shown in the area C of fig. 4, when receiving the external reset command, the first pwm circuit 412 recovers to the normal output, i.e. outputs the duty ratio and the pulse signal V₁Pulse signal V keeping consistency₂. If at this time V_CINReaching or exceeding a first threshold value V_CINTH+No longer present, the first pulse width is adjustedWay 412 continues to maintain output duty cycle and pulse signal V₁Pulse signal V keeping consistency₂。

In other embodiments of the present application, when the current of the power supply circuit 102 of the load 101 is in the normal range, the first pulse width modulation circuit 412 outputs the duty ratio and the pulse signal V₁Pulse signal V with fixed proportional relation of duty ratio₂The output pulse signal V2 can be regulated and controlled conveniently, and the pulse signal V2 suitable for the current gear of the pulse ablation instrument is generated. For example, the first pulse width adjusting circuit 412 outputs a pulse signal V having a duty ratio₁0.4, 0.5, 0.6, 0.7, 0.8, 1.2, 1.3, 1.4, 1.5, 1.6 times of the duty cycle of (a)₂。

Further, the first pulse width adjusting circuit 412 may further include a comparator 4122, a flip-flop 4123, and a pulse regulation second sub-circuit 4124. The non-inverting input terminal of the comparator 4122 is connected to the sampled value, and the inverting input terminal of the comparator 4122 is connected to the second threshold value. In the case where the sample value is larger than the second threshold value, the comparator 4122 outputs a trigger level. Specifically, the comparator may be of the type LM 193. The second threshold value of the comparator may be a reference voltage. The reference voltage can be output by the connection end of the fixed resistor and the adjustable resistor which are connected in series. One end of the fixed resistor is connected with the adjustable resistor, and the other end of the fixed resistor is connected with a power supply VCC. One end of the adjustable resistor is connected with the constant value resistor, and the other end of the adjustable resistor is grounded. The adjustable resistors shown in fig. 3 are R1 and R18, and the fixed resistors are R4 and R16, and by adjusting the adjustable resistors R1 and R18, the second threshold value can be modified and adjusted according to actual conditions, so that the application range is wider. The flip-flop 4123 is configured to receive a trigger level and continuously output a control signal to the CIN pin of the pulse-controlled second sub-circuit 4124.

In some examples, as shown in fig. 3, the pulse-controlled first sub-circuit 4121 and the pulse-controlled second sub-circuit 4124 are the same chip, the CIN pin of the pulse-controlled first sub-circuit 4121 and the CIN pin of the pulse-controlled second sub-circuit 4124 are the same pin, and the over-current protection and the short-circuit protection for the circuit where the load and the pulse switch circuit are located are implemented by the same CIN pin in the first pulse width adjusting circuit 412.

Specifically, the flip-flop 4123 may be a D flip-flop or an RS flip-flop or the like. The flip-flop 4123 in the embodiment shown in fig. 3 is a D flip-flop, and more specifically, the model of the D flip-flop may be CD 4013. When the flip-flop 4123 is an RS flip-flop or other flip-flops, the circuit configuration of the flip-flop 4123 in the embodiment shown in fig. 3 needs to be modified accordingly to meet the level control logic. The pulse control second sub-circuit 4124 is configured to decrease the duty ratio of the pulse signal cycle by cycle according to the control signal until the duty ratio of the pulse signal decreases to zero. That is to say, when the pulse-controlled second sub-circuit 4124 receives the trigger level output by the comparator 4122, that is, the sampling value is greater than the second threshold value, the pulse-controlled second sub-circuit 4124 decreases the duty ratio of the pulse signal and outputs the pulse signal after the decreased duty ratio, and when the next period of the pulse signal comes, the pulse-controlled second sub-circuit 4124 continues to decrease the duty ratio of the current period of the pulse signal and outputs the pulse signal until the duty ratio of the current period of the pulse signal decreases to zero, so as to slowly turn off the pulse switching circuit 2, and achieve the effect of power-off soft landing, thereby achieving the protection of the pulse ablator and the load.

Further, when the pulse-controlled second sub-circuit 4124 receives the trigger level output by the comparator 4122, that is, the sampling value is greater than the second threshold, the rate at which the pulse-controlled second sub-circuit 4124 reduces the duty ratio of the pulse signal is faster than the rate at which the sampling value received by the pulse-controlled first sub-circuit 4121 is greater than the first threshold, so that the circuit safety of the pulse ablation instrument when the short circuit condition of the power supply circuit of the load occurs can be improved. Thus, the switch control circuit 4 can implement short-circuit protection for the load and the circuit where the pulse switch circuit is located through the first pulse width modulation circuit 412.

The pulse-controlled first sub-circuit 4121 and the pulse-controlled second sub-circuit 4124 may be a same integrated circuit, for example, the function of reducing the duty ratio of the pulse signal cycle by cycle of the pulse-controlled first sub-circuit 4121 and the pulse-controlled second sub-circuit 4124 may be implemented by a same chip of the type FAN 3181. Alternatively, the pulse-controlled first sub-circuit 4121 and the pulse-controlled second sub-circuit 4124 may be two identical integrated circuits, for example, the pulse-controlled first sub-circuit 4121 and the pulse-controlled second sub-circuit 4124 may be two identical FAN3181 chips. Alternatively, the first pulse-controlled sub-circuit 4121 and the second pulse-controlled sub-circuit 4124 may also be two different integrated circuits, the duty cycle of the pulse signal that is reduced by the two different integrated circuits may be different, and the rate at which the integrated circuit corresponding to the second pulse-controlled sub-circuit 4124 reduces the duty cycle of the pulse signal by the cycles may be faster than the rate at which the integrated circuit corresponding to the first pulse-controlled sub-circuit 4121 reduces the duty cycle of the pulse signal by the cycles. For example, the first pulse-controlled sub-circuit 4121 may be a FAN3181 chip and the second pulse-controlled sub-circuit 4124 may be another integrated circuit.

The pulse ablator 100 may also include a main control unit 5 and an alarm unit 6. Referring to fig. 3, when the sampling value is greater than the second threshold value, the trigger 4123 further sends a control signal to the main control unit 5 through the diode D1 and the diode D2, and then the main control unit 5 controls the alarm unit 6 to alarm, where the alarm may be an audible and visual alarm. The main control unit 5 may also send a reset signal to the flip-flop 4123 according to an external reset instruction to reset the flip-flop 4123 and stop outputting the control signal. The control signal is sent to the main control unit 5 through the diode, so that the influence of the internal voltage of the main control unit 5 on the control signal can be avoided, the control signal can be prevented from being influenced, the duty ratio of the pulse signal is reduced periodically by the pulse regulation and control second sub-circuit 4124 until the duty ratio of the pulse signal is reduced to zero, and the improvement of the functional operation stability of the short-circuit protection of the pulse regulation and control second sub-circuit is facilitated. In a specific application scenario, when a short circuit condition occurs, the sampling value obtained by the sampling circuit 3 is greater than the second threshold value, so that the trigger 4123 sends the control signal to the main control unit 5 through the diode D1 and the diode D2, and the main control unit 5 controls the alarm unit 6 to alarm. When an operator hears an alarm sound or the alarm is turned on, the short-circuit condition of the pulse ablation instrument 100 and the load 101 is detected, and after the short-circuit fault is eliminated, a reset key of the pulse ablation instrument 100 can be pressed or an external reset instruction is sent to the main control unit 5 in other modes, so that the trigger 4123 can be reset, and the internal circuit of the pulse ablation instrument can work normally again.

In other embodiments, referring to fig. 5, the pulse control circuit 41 includes a second pulse width adjusting circuit 413 and a second pulse generator 414. The second pulse width adjusting circuit 413 is electrically connected to the sampling circuit 3, and is configured to generate a duty ratio adjusting signal according to the sampling value. The second pulse generator 414 is electrically connected to the second pulse width adjusting circuit 413 and the driving circuit 43, and is configured to generate a pulse signal according to a duty ratio adjusting signal, where the duty ratio of the pulse signal is adjusted by the duty ratio adjusting signal, and the duty ratio adjusting signal controls the second pulse generator 414 to generate a pulse signal with a controlled duty ratio.

The second pulse width modulation circuit 413 may comprise a microprocessor. The microprocessor of the second pulse width adjusting circuit 413 may receive the sampled value and output the duty ratio regulation signal according to the sampled value through internal processing of the microprocessor. Specifically, in the case that the sampling value is greater than the first threshold value, the second pulse width adjusting circuit 413 may output the duty ratio regulating signal to decrease the duty ratio of the pulse signal output by the second pulse generator 414 cycle by cycle, so as to decrease the duty ratio of the driving signal output by the driving circuit 43 cycle by cycle until the sampling value is less than or equal to the first threshold value. In the case that the sampling value is greater than the second threshold value, the second pulse width adjusting circuit 413 may output a duty ratio adjusting signal to decrease the duty ratio of the pulse signal cycle by cycle, thereby decreasing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops operating. Wherein the second threshold is greater than the first threshold. Therefore, the switch control circuit 4 can simultaneously realize the overcurrent protection and the short-circuit protection of the load and the circuit where the pulse switch circuit is located through the second pulse width adjusting circuit 413.

That is, when the sampling value received by the microprocessor is greater than the first threshold value, the microprocessor of the second pulse width adjusting circuit 413 directly controls the second pulse generator 414 to decrease the duty ratio of the output pulse signal according to the preset duty ratio manner of decreasing the output pulse signal by the duty ratio adjusting signal. When the next period of the pulse signal comes, if the sampling value received by the microprocessor is still greater than the first threshold value, the microprocessor of the second pulse width adjusting circuit 413 continues to control the second pulse generator 414 to decrease the duty ratio of the output pulse signal until the sampling value received by the microprocessor is less than or equal to the first threshold value. Under the condition that the sampling value received by the microprocessor is greater than the second threshold value, the microprocessor of the second pulse width adjusting circuit 413 directly controls the second pulse generator 414 to reduce the duty ratio of the output pulse signal through the duty ratio regulating and controlling signal according to a preset duty ratio mode of reducing the output pulse signal. When the next period of the pulse signal comes, if the duty ratio of the pulse signal is not reduced to zero, the microprocessor of the second pulse width adjusting circuit 413 continues to control the second pulse generator 414 to reduce the duty ratio of the output pulse signal until the pulse switching circuit stops working.

When the power circuit 1 and the pulse switch circuit 2 are used to output a pulse current with a single polarity to a load, the second pulse generator 414 can be used to generate a pulse signal with a fixed duty ratio. When the power circuit 1 and the pulse switch circuit 2 are used to output bipolar pulse current to the load 101, the second pulse generator 414 can be a complementary symmetric PWM waveform generator, and can simultaneously generate and output a pair of pulse signals with the same frequency and duty ratio and 180 degrees phase difference.

Referring to fig. 6, a method for controlling a pulse ablator according to an embodiment of the present application includes:

s01: sampling current flowing through a power supply loop of a load and obtaining a sampling value;

s02: and when the sampling value is larger than the threshold value, reducing the duty ratio of a driving signal for controlling the pulse switching circuit to work so as to reduce the current output to the load.

The control method of the pulse ablation instrument obtains the sampling value by sampling the current flowing through the load and the power supply loop of the load, and when the sampling value is larger than the threshold value, the duty ratio of the pulse signal is reduced to reduce the current output to the load, so that the current flowing through the load and the power supply loop of the load can be reduced in real time when the current flowing through the load and the power supply loop of the load is overlarge, the effect of protecting a switching device in a pulse switching circuit is achieved, and the switching device is prevented from being damaged due to continuous heavy current impact. In addition, the control method of the pulse ablation instrument can also avoid that the load is under long-time heavy current, so that damage to the load can be avoided.

In particular, the pulse ablator control method may be implemented by processor control. Referring to fig. 7, in the control method of the pulse ablator, the processor may first read preset pulse parameters, where the preset pulse parameters may include preset duty cycle values, preset frequency values, and the like. Then, the processor controls the pulse generator to output a pulse waveform according to the preset value of the pulse parameter. Then, the sampling circuit samples the current flowing through the power supply loop of the load to obtain a sampling value and sends the sampling value to the processor, and the processor receives, reads and judges whether the sampling value exceeds a threshold value. And under the condition that the sampling value reaches or exceeds the threshold value, the processor reduces the duty ratio preset value in the pulse parameter preset values and modifies a register, the register is used for storing the pulse parameter preset values, and then the processor reads the modified pulse parameter preset values again and controls the pulse generator to output pulse waveforms according to the modified pulse parameter preset values. In the case that the sample value does not reach and does not exceed the threshold value, the processor returns to the step of receiving and reading the sample value, and continuously monitors whether the sample value reaches or exceeds the threshold value. Therefore, the control method of the pulse ablation instrument can reduce the current flowing through the load and the power supply loop where the load is located in real time in a software control mode under the condition that the current flowing through the load is overlarge, so that the effect of protecting the power supply loop is achieved, and the power supply loop is prevented from being damaged due to the impact of large current. In addition, the load can be prevented from being under a large current for a long time, so that the damage to the load can be avoided.

When the processor receives an external reset instruction, the pulse parameter preset value is reset to an initial value preset by the processor and the register is modified. Therefore, after the pulse ablation instrument is reset by the pulse ablation instrument control method, the pulse generator can be controlled to output the pulse waveform according to the initial value preset by the processor.

Referring to fig. 8, in some embodiments of the method for controlling a pulse ablator, the threshold value comprises a first threshold value, and in the case that the sampled value is greater than the threshold value, decreasing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit (S02) comprises:

s021: and under the condition that the sampling value is larger than the first threshold value, reducing the duty ratio of the driving signal cycle by cycle until the sampling value is smaller than or equal to the first threshold value.

The first threshold may correspond to a threshold that the sampling value exceeds when the load current is too large, and specific values thereof may refer to the foregoing, and description thereof is not repeated here. The step of reducing the duty ratio of the driving signal cycle by cycle until the sampling value is less than or equal to the first threshold value comprises continuously judging whether the sampling value of the current cycle is less than or equal to the first threshold value, and if so, stopping reducing the duty ratio of the driving signal; if not, the duty ratio of the driving signal is continuously reduced in the next period until the sampling value is smaller than or equal to the first threshold value. Therefore, the pulse ablation instrument control method realizes that when the current flowing through the power supply loop of the load is overlarge, the duty ratio of the driving signal is reduced, the current output to the load is reduced until the current flowing through the power supply loop of the load is recovered to be normal, and the overcurrent protection of the load and the power supply loop of the load is realized.

Referring to fig. 9, in some embodiments of the method for controlling a pulse ablatograph, the threshold value includes a first threshold value and a second threshold value, and in the case that the sampled value is greater than the threshold value, decreasing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit (S02) includes:

s022: and under the condition that the sampling value is larger than the second threshold value, the duty ratio of the driving signal is reduced cycle by cycle until the pulse switching circuit stops working. Wherein the second threshold is greater than the first threshold.

The first threshold may correspond to a threshold that a sampling value exceeds when the load current is too large, and the second threshold may correspond to a threshold that a sampling value exceeds when the load is short-circuited. Specific values of the first threshold and the second threshold may refer to the above, and a description thereof is not repeated here. The step of reducing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops working comprises continuously judging whether the duty ratio of the pulse signal in the current cycle is reduced to zero, and if so, stopping reducing the duty ratio of the driving signal; if not, the duty ratio of the driving signal is continuously reduced in the next period until the pulse switching circuit stops working. Therefore, under the condition that the power supply loop of the load is in a short circuit state, the control method of the pulse ablation instrument can enable the current output to the load to be gradually reduced, the switching device is closed in a soft landing mode, the phenomenon that the induced voltage spike is caused by large current transient change can be avoided, the circuit safety of the process of closing the pulse switching circuit when the load is in a short circuit state is improved, and the short circuit protection of the load and the power supply loop of the load is realized.

Referring to fig. 10, in some embodiments of the method for controlling a pulse ablatograph, the threshold value includes a first threshold value and a second threshold value, and in the case that the sampled value is greater than the threshold value, decreasing the duty cycle of the driving signal for controlling the operation of the pulse switching circuit (S02) includes:

s021: under the condition that the sampling value is larger than a first threshold value, the duty ratio of the driving signal is reduced cycle by cycle until the sampling value is smaller than or equal to the first threshold value; and

s022: and under the condition that the sampling value is larger than the second threshold value, the duty ratio of the driving signal is reduced cycle by cycle until the pulse switching circuit stops working. Wherein the second threshold is greater than the first threshold.

The first threshold may correspond to a threshold that a sampling value exceeds when the load current is too large, and the second threshold may correspond to a threshold that a sampling value exceeds when the load is short-circuited. Specific values of the first threshold and the second threshold may refer to the above, and a description thereof is not repeated here. The step of reducing the duty ratio of the driving signal cycle by cycle until the sampling value is less than or equal to the first threshold value comprises continuously judging whether the sampling value of the current cycle is less than or equal to the first threshold value, and if so, stopping reducing the duty ratio of the driving signal; if not, the duty ratio of the driving signal is continuously reduced in the next period until the sampling value is smaller than or equal to the first threshold value. The step of reducing the duty ratio of the driving signal cycle by cycle until the pulse switching circuit stops working comprises continuously judging whether the duty ratio of the pulse signal in the current cycle is reduced to zero, and if so, stopping reducing the duty ratio of the driving signal; if not, the duty ratio of the driving signal is continuously reduced in the next period until the pulse switching circuit stops working. Therefore, the pulse ablation instrument control method realizes that when the current flowing through the power supply loop of the load is overlarge, the duty ratio of the driving signal is reduced, the current output to the load is reduced until the current flowing through the power supply loop of the load is recovered to be normal, and the overcurrent protection of the load and the power supply loop of the load is realized. In addition, under the condition that the power supply loop of the load is in a short circuit state, the control method of the pulse ablation instrument can enable the current output to the load to be gradually reduced, the switching device is closed in a soft landing mode, the phenomenon that the induced voltage spike is caused by large current transient change can be avoided, the circuit safety of the process of closing the pulse switching circuit when the load is in a short circuit state is improved, and the short circuit protection of the load and the power supply loop of the load is realized.

In summary, the pulse ablation instrument and the control method thereof according to the embodiments of the present application obtain the sampling value by setting the sampling circuit to sample the current flowing through the load and the power supply loop of the load, and when the sampling value is greater than the threshold value, the duty ratio of the pulse signal is reduced by the switch control circuit to reduce the output current of the power supply circuit, so that when the current flowing through the load and the power supply loop of the load is too large, the current flowing through the load and the power supply loop of the load is reduced in real time, an effect of protecting the switching device in the pulse switching circuit is achieved, and the switching device is prevented from being damaged due to continuous large current impact. In addition, the pulse ablation instrument and the control method thereof can also prevent the load from being under large current for a long time, so that damage to the load can be avoided.

In the description of embodiments of the present application, any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and the scope of the preferred embodiments of the present application includes additional implementations in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present application.

The logic and/or steps represented in the flowcharts or otherwise described herein, such as an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processing module-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection having one or more wires (control method), a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the embodiments of the present application may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.