阅读说明：本技术 直流高压发生装置 (DC high voltage generator ) 是由 张欣 吕启深 詹威鹏 张�林 廖姗姗 于 2021-07-02 设计创作，主要内容包括：本发明涉及一种直流高压发生装置,包括：整流单元,用于提供初始直流信号；高频逆变单元,与整流单元连接,用于根据直流信号生成第一交流信号；高频变压单元,与高频逆变单元连接,用于将第一交流信号转化为第二交流信号,第二交流信号大于第一交流信号；直流倍压单元,与高频变压单元连接,用于根据第二交流信号生成预设电压值的直流高压。该装置不仅更加小型化而且还能输出更稳定的直流信号。(The invention relates to a direct current high voltage generating device, comprising: a rectifying unit for providing an initial DC signal; the high-frequency inversion unit is connected with the rectification unit and used for generating a first alternating current signal according to the direct current signal; the high-frequency transformation unit is connected with the high-frequency inversion unit and used for converting the first alternating current signal into a second alternating current signal, and the second alternating current signal is larger than the first alternating current signal; and the direct current voltage doubling unit is connected with the high-frequency voltage transformation unit and is used for generating a direct current high voltage with a preset voltage value according to the second alternating current signal. The device is not only more miniaturized but also can output more stable direct current signals.)

1. A direct current high voltage generating device, comprising:

a rectifying unit for providing an initial DC signal;

the high-frequency inversion unit is connected with the rectification unit and used for generating a first alternating current signal according to the direct current signal;

the high-frequency transformation unit is connected with the high-frequency inversion unit and used for converting the first alternating current signal into a second alternating current signal, and the voltage value of the second alternating current signal is greater than that of the first alternating current signal;

and the direct current voltage doubling unit is connected with the high-frequency voltage transformation unit and is used for generating a direct current high voltage with a preset voltage value according to the second alternating current signal.

2. The apparatus of claim 1, wherein the rectification unit comprises:

the power frequency power supply is used for providing a power frequency alternating current signal;

the rectifying circuit is connected with the power frequency power supply and used for rectifying the power frequency alternating current signal into a first direct current signal;

and the filter circuit is connected with the rectifying circuit and used for acquiring an initial direct current signal according to the first direct current signal, and the ripple wave of the initial direct current signal is lower than that of the first direct current signal.

3. The apparatus of claim 2, wherein the filtering circuit comprises:

the smoothing circuit comprises a smoothing inductor and a filter capacitor, wherein the smoothing inductor and the filter capacitor are connected between two output ends of the rectifying circuit in series.

4. The apparatus of claim 2, wherein the rectification circuit comprises:

the anode of the first diode is connected with the anode of the power frequency power supply;

a second diode, a cathode of the second diode being connected to an anode of the first diode;

the anode of the third diode is connected with the cathode of the power frequency power supply, and the cathode of the third diode is connected with the cathode of the first diode;

the anode of the fourth diode is connected with the anode of the second diode, and the cathode of the fourth diode is connected with the anode of the third diode;

and a node between the cathode of the first diode and the cathode of the third diode is used as one output end of the rectifying circuit, and the anode of the second diode and the anode of the fourth diode are used as the other output end of the rectifying circuit.

5. The apparatus of claim 1, wherein the rectifying unit comprises two output terminals, the high frequency transforming unit comprises two input terminals, and the high frequency inverting unit comprises:

a collector of the first transistor is connected with a first output end of the rectifying unit, an emitter of the first transistor is connected with a first input end of the high-frequency voltage transformation unit, a gate of the first transistor is used for receiving a first control signal, and the first control signal is used for controlling the on-off of each first transistor;

a collector of the second transistor is connected with an emitter of the first transistor, the emitter of the second transistor is connected with a second output end of the rectifying unit, a gate of the second transistor is used for receiving a second control signal, and the second control signal is used for controlling the on-off of each second transistor;

a collector of the third transistor is connected with a collector of the first transistor, an emitter of the third transistor is connected with the second input end of the high-frequency transformation unit, a gate of the third transistor is used for receiving a third control signal, and the third control signal is used for controlling the on-off of each third transistor;

and a collector of the fourth transistor is connected with an emitter of the third transistor, an emitter of the fourth transistor is connected with an emitter of the second transistor, a gate of the fourth transistor is used for receiving a fourth control signal, and the fourth control signal is used for controlling the on-off of each fourth transistor.

6. The apparatus of claim 1, wherein the dc voltage doubling unit comprises: the input end of the voltage doubling circuit of the first stage is connected with the output end of the high-frequency transformation unit, the input end of the voltage doubling circuit of the mth stage is correspondingly connected with the output end of the voltage doubling circuit of the (m-1) th stage, the voltage doubling circuit of the nth stage is used for outputting the direct-current high voltage, wherein m is more than 1 and less than or equal to n, and m and n are both positive integers.

7. The apparatus of claim 6, wherein the voltage doubling circuit comprises:

one end of the first capacitor is used as a first input port;

a negative electrode of the fifth diode is connected with the other end of the first capacitor;

a sixth diode, an anode of the sixth diode being connected to an anode of the fifth diode;

wherein a node between the fifth diode and the sixth diode serves as a second input port;

one end of the second capacitor is connected with the cathode of the sixth diode, and the other end of the second capacitor is used as a third input port;

a seventh diode, an anode of the seventh diode being connected to a cathode of the fifth diode;

the cathode of the eighth diode is connected with the cathode of the seventh diode, and the anode of the eighth diode is connected with the cathode of the sixth diode;

a node at which the anode of the seventh diode is connected to the cathode of the fifth diode serves as a first output port;

a connection point of the seventh diode and the eighth diode serves as a second output port;

a node at which the anode of the eighth diode is connected with the cathode of the sixth diode serves as a third output port;

and the third capacitor is respectively connected with the anode of the fifth diode and the cathode of the seventh diode.

8. The apparatus of claim 7, wherein the high frequency transforming unit comprises two output ports, a first input port of the first stage voltage doubling circuit is connected to the first output port of the high frequency transforming unit, a second input port is used for grounding, and a third input port is connected to the second output port of the high frequency transforming unit.

9. The apparatus of claim 7, wherein the second output port of the nth stage voltage doubling circuit is configured to be connected to a load.

10. The apparatus of claim 6, wherein the preset voltage value is n times the voltage value of the second AC signal.

Technical Field

The invention relates to the field of direct-current high-voltage testing and detection, in particular to a direct-current high-voltage generating device.

Background

At present, the direct current high voltage generator is widely used in domestic transformer substations and electric power science research institutes. For example, the insulation strength of converter station equipment and insulating materials in a direct-current high-voltage transmission system under direct-current high-voltage signals, the corona effect of a direct-current transmission line, the detection of the electrical insulation strength and leakage current of high-voltage power equipment and the like are researched. Therefore, the dc high voltage generator is a critical instrument for performing high voltage signal tests.

With the rapid development of microelectronic technology and power electronic technology, the conventional dc high-voltage power supply rectifies an ac signal into a dc signal by using a high-voltage transformer and a high-voltage silicon stack, and the whole system has the disadvantages of large ripple factor, large volume, heavy mass and the like, which cannot meet the requirements of related researchers.

Disclosure of Invention

In view of this, it is necessary to provide a stable and compact dc high voltage generator.

A direct current high voltage generating device comprising:

a rectifying unit for providing an initial DC signal;

the high-frequency inversion unit is connected with the rectification unit and used for generating a first alternating current signal according to the direct current signal;

the high-frequency transformation unit is connected with the high-frequency inversion unit and used for converting the first alternating current signal into a second alternating current signal, and the voltage value of the second alternating current signal is greater than that of the first alternating current signal;

and the direct current voltage doubling unit is connected with the high-frequency voltage transformation unit and is used for generating a direct current high voltage with a preset voltage value according to the second alternating current signal.

In one embodiment, the rectifying unit includes:

the power frequency power supply is used for providing a power frequency alternating current signal;

the rectifying circuit is connected with the power frequency power supply and used for rectifying the power frequency alternating current signal into a first direct current signal;

and the filter circuit is connected with the rectifying circuit and used for acquiring an initial direct current signal according to the first direct current signal, and the ripple wave of the initial direct current signal is lower than that of the first direct current signal.

In one embodiment, a filter circuit includes:

the smoothing inductor and the filter capacitor are connected between two output ends of the rectifying circuit in series.

In one embodiment, a rectifier circuit includes:

the anode of the first diode is connected with the anode of the power frequency power supply;

the cathode of the second diode is connected with the anode of the first diode;

the anode of the third diode is connected with the cathode of the power frequency power supply, and the cathode of the third diode is connected with the cathode of the first diode;

the anode of the fourth diode is connected with the anode of the second diode, and the cathode of the fourth diode is connected with the anode of the third diode;

and a node between the cathode of the first diode and the cathode of the third diode is used as one output end of the rectifying circuit, and the anode of the second diode and the anode of the fourth diode are used as the other output end of the rectifying circuit.

In one embodiment, the rectifying unit includes two output terminals, the high frequency transforming unit includes two input terminals, and the high frequency inverting unit includes:

the collector of the first transistor is connected with the first output end of the rectifying unit, the emitter of the first transistor is connected with the first input end of the high-frequency voltage transformation unit, the gate of the first transistor is used for receiving a first control signal, and the first control signal is used for controlling the on-off of each first transistor;

a collector of the second transistor is connected with an emitter of the first transistor, the emitter is connected with a second output end of the rectifying unit, a gate of the second transistor is used for receiving a second control signal, and the second control signal is used for controlling the on-off of each second transistor;

the collector electrode of the third transistor is connected with the collector electrode of the first transistor, the emitter electrode of the third transistor is connected with the second input end of the high-frequency voltage transformation unit, the gate electrode of the third transistor is used for receiving a third control signal, and the third control signal is used for controlling the on-off of each third transistor;

and the collector electrode of the fourth transistor is connected with the emitter electrode of the third transistor, the emitter electrode of the fourth transistor is connected with the emitter electrode of the second transistor, the gate electrode of the fourth transistor is used for receiving a fourth control signal, and the fourth control signal is used for controlling the on-off of each fourth transistor.

In one embodiment, the dc voltage doubling unit includes: the input end of the first-stage voltage doubling circuit is connected with the output end of the high-frequency transformation unit, the input end of the mth-stage voltage doubling circuit is correspondingly connected with the output end of the (m-1) -th-stage voltage doubling circuit, the nth-stage voltage doubling circuit is used for outputting direct-current high voltage, wherein m is more than 1 and less than or equal to n, and m and n are positive integers.

In one embodiment, the voltage doubling circuit comprises:

one end of the first capacitor is used as a first input port;

the cathode of the fifth diode is connected with the other end of the first capacitor;

the anode of the sixth diode is connected with the anode of the fifth diode;

a node between the fifth diode and the sixth diode is used as a second input port;

the second capacitor is connected with the cathode of the sixth diode at one end, and the other end of the second capacitor is used as a third input port;

the anode of the seventh diode is connected with the cathode of the fifth diode;

the cathode of the eighth diode is connected with the cathode of the seventh diode, and the anode of the eighth diode is connected with the cathode of the sixth diode;

a node, in which the anode of the seventh diode is connected to the cathode of the fifth diode, serves as a first output port;

the connection point of the seventh diode and the eighth diode is used as a second output port;

a node at which the anode of the eighth diode is connected with the cathode of the sixth diode serves as a third output port;

and the third capacitor is respectively connected with the anode of the fifth diode and the cathode of the seventh diode.

In one embodiment, the high-frequency transforming unit includes two output ports, a first input port of the first stage voltage-doubling circuit is connected with the first output port of the high-frequency transforming unit, a second input port is used for grounding, and a third input port is connected with the second output port of the high-frequency transforming unit.

In one embodiment, the second output port of the nth stage voltage doubling circuit is used for connecting a load.

In one embodiment, the preset voltage value is n times of the voltage value of the second alternating current signal.

The direct current high voltage generating device comprises a rectifying unit, a voltage regulating unit and a voltage regulating unit, wherein the rectifying unit is used for providing an initial direct current signal; the high-frequency inversion unit is connected with the rectification unit and used for generating a first alternating current signal according to the direct current signal; the high-frequency transformation unit is connected with the high-frequency inversion unit and used for converting the first alternating current signal into a second alternating current signal, and the second alternating current signal is larger than the first alternating current signal; and the direct current voltage doubling unit is connected with the high-frequency voltage transformation unit and is used for generating a first direct current high voltage according to the second alternating current signal. The voltage signal of the invention is directly obtained from the high-frequency voltage transformation unit, the direct-current high voltage is realized through voltage doubling, and compared with the voltage signal output by the traditional voltage doubling circuit, the voltage drop is lower, namely, the potential difference is lower and more stable; and direct current voltage doubling unit can generate the direct current high voltage of predetermineeing the voltage value as required, promotes the voltage value of output easily, for in the conventional art, can effectively avoid the use of expensive, the high voltage direct current power that can not expand, has also promoted the scalability of module simultaneously.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the conventional technologies of the present application, the drawings used in the descriptions of the embodiments or the conventional technologies will be briefly introduced below, it is obvious that the drawings in the following descriptions are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a DC high voltage generator according to an embodiment;

FIG. 2 is a schematic structural diagram of a rectifying unit in an embodiment;

FIG. 3 is a circuit diagram of a rectifying unit in one embodiment;

FIG. 4 is a circuit diagram of a high frequency inverter unit according to an embodiment;

FIG. 5 is a circuit diagram of a DC high voltage generator according to an embodiment;

FIG. 6 is a schematic diagram illustrating the charging of two third capacitors with an AC signal according to an embodiment;

FIG. 7 is a second schematic diagram illustrating the charging of two third capacitors of the AC signal according to an embodiment;

FIG. 8 is a diagram illustrating discharge of two third capacitors in an embodiment.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Embodiments of the present application are set forth in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

It will be understood that, as used herein, the terms "first," "second," and the like may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first diode may be referred to as a second diode, and similarly, a second diode may be referred to as a first diode, without departing from the scope of the present application. The first diode and the second diode are both diodes, but they are not the same diode.

It is to be understood that "connection" in the following embodiments is to be understood as "electrical connection", "communication connection", and the like if the connected circuits, modules, units, and the like have communication of electrical signals or data with each other.

As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising," "includes" or "including," etc., specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

In the description herein, references to the description of "some embodiments," "other embodiments," "desired embodiments," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, a schematic description of the above terminology may not necessarily refer to the same embodiment or example.

In one embodiment, as shown in FIG. 1, a schematic diagram of a DC high voltage generator is provided. The dc high voltage generating apparatus 100 includes a rectifying unit 110, a high frequency inverting unit 120, a high frequency transforming unit 130, and a dc voltage doubling unit 140. The rectifying unit 110 is configured to provide an initial dc signal for the entire system, and an input end of the high-frequency inverting unit 120 is connected to an input end of the rectifying unit 110, and is configured to generate a first ac signal according to the initial dc signal; the input end of the high-frequency transformation unit 130 is connected with the output end of the high-frequency inversion unit 130, and the high-frequency transformation unit 130 is used for converting the first alternating current signal into a second alternating current signal with a higher voltage signal value; the input end of the dc voltage doubling unit 140 is connected to the output end of the high frequency transforming unit 130, and the dc voltage doubling unit 140 is configured to convert the second ac signal with a higher voltage value into a dc high voltage with a higher preset voltage value.

The above-mentioned embodiment provides a device capable of outputting a dc high voltage signal, which has a compact circuit structure and the potential of realizing modularization, and is capable of outputting a more stable dc high voltage with a preset voltage value. Compare and directly obtain alternating current signal from power frequency power supply among the conventional art to through voltage doubling circuit output direct current high voltage signal, the alternating current signal of this scheme is got from high frequency voltage transformation unit, realizes direct current high pressure through direct current voltage doubling unit, and its voltage drop is lower, and is more stable, has the faster advantage of the speed of charging. Meanwhile, the small-sized modular design does not need a large-sized high-voltage transformer, the manufacturing cost is lower, and great convenience is brought to various field detection.

In one embodiment, as shown in fig. 2, a schematic diagram of a rectifying unit is provided, and the rectifying unit 110 includes a power frequency power supply 111, a rectifying circuit 113, and a filtering circuit 115. The input end of the rectifying circuit 113 is connected with the positive and negative output ends of the power frequency power supply 111 in a one-to-one correspondence manner, and the rectifying circuit 113 is used for rectifying the power frequency alternating current signal into a first direct current signal; the input end of the filter circuit 115 is connected to the output port of the rectifying circuit 113, and the filter circuit 115 is configured to obtain an initial dc signal with smaller ripple according to the first dc signal.

The ripple is a phenomenon caused by voltage signal fluctuation of the dc regulated power supply, and the element in the circuit is damaged due to the too large ripple, so in the above embodiment, the ac signal can be converted into the first dc signal with smaller ripple and more stability through the combination of the rectifier circuit and the filter circuit.

In one embodiment, as shown in FIG. 3, a circuit diagram of a rectifying unit is provided, in which a filter circuit 115 includes a smoothing inductor L₀And a filter capacitor C₀And the two are connected in series between two output ends of the rectifying circuit.

The smoothing inductor can effectively restrain over-current flowing through the diode at the moment of power-on, the influence of the power-on moment on a power system is reduced, and the output direct current ripple wave which can be formed by the serial combination of the smoothing inductor and the filter capacitor is smaller and is closer to ideal direct current.

In one embodiment, the filter capacitor C₀Is an aluminum electrolytic capacitor. The aluminum electrolytic capacitor is larger than other capacitors, and the ripple factor can be effectively reduced.

In one embodiment, continuing with FIG. 3, the rectifying circuit 113 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The anode of the first diode D1 is connected with the anode of the power frequency power supply 111; the cathode of the second diode D2 is connected with the anode of the first diode D1; the anode of the third diode D3 is connected with the cathode of the industrial frequency power supply 111, and the cathode of D3 is connected with the cathode of the first diode; the anode of the fourth diode D4 is connected to the anode of the second diode D2, and the cathode of D4 is connected to the anode of the third diode D3. A node between the cathode of the first diode D1 and the cathode of the third diode D3 serves as one output terminal of the rectifying circuit 113, and a node between the anode of the second diode D2 and the anode of the fourth diode D4 serves as the other output terminal of the rectifying circuit 113.

In one embodiment, as shown in fig. 4, a circuit diagram of a high frequency inverting unit 120 is provided, the high frequency inverting unit 120 including a first transistor T1, a second transistor T2, a third transistor T3, and a fourth transistor T4. The high-frequency voltage transformation unit comprises a first input end and a second input end, a collector of a first transistor T1 in the high-frequency inversion unit is connected with the first output end of the rectification unit, an emitter of the first transistor T1 is connected with the first input end of the high-frequency voltage transformation unit, and a gate of the high-frequency voltage transformation unit is used for receiving a first control signal to control the on-off of the first transistor; the collector of the second transistor T2 is connected to the emitter of the first transistor T1, the emitter is connected to the second output terminal of the rectifying unit, and the gate is used to receive a second control signal to control the on/off of the second transistor T2; the collector of the third transistor T3 is connected to the collector of the first transistor T1, the emitter is connected to the second input terminal of the high frequency transformer unit, and the gate is used to receive a third control signal to control the on/off of the third transistor T3; the collector of the fourth transistor T4 is connected to the emitter of the third transistor T3, the emitter is connected to the emitter of the second transistor T2, and the gate is used to receive a fourth control signal to control the on/off of the fourth transistor.

In one embodiment, continuing with fig. 4, there are 4 Insulated Gate Bipolar Transistors (IGBTs) with parallel diodes, including a first Transistor T1, a second Transistor T2, a third Transistor T3, a fourth Transistor T4, a first body diode D_T1Second body diode D_T2A third body diode D_T3A fourth body diode D_T4. The positive electrode of each body diode is connected to the emitter of the corresponding transistor, and the negative electrode is connected to the collector of the corresponding transistor. Each transistor is connected with the corresponding body diode, so that abnormal conduction of the circuit can be effectively prevented, and the circuit is protected.

Each transistor is further connected with a corresponding driving circuit, an isolation power supply and a control circuit, and in order to make the circuit diagram simple, fig. 4 does not show each driving circuit, isolation power supply and control circuit. The positive and negative electrodes of each isolated power supply are connected with each corresponding driving circuit, each control circuit is connected with each corresponding driving circuit, and the gate pole and the emitter of each transistor are connected with each corresponding driving circuit. Each driving circuit can provide +15V and-8V driving voltage between a gate electrode and an emitter electrode of each transistor, an isolation power supply connected with each driving circuit can isolate 3kV voltage, so that the driving circuit of each transistor realizes isolation power supply, and the control circuit transmits driving signals and controls output voltage through a pulse width modulation method.

The alternating voltage controlled and output by the pulse width modulation method can be used as a high-frequency voltage source to charge a post-stage circuit through the high-frequency voltage transformation unit. The voltage amplitude of the secondary side of the transformer can be adjusted by controlling the voltage pulse width of the primary side of the high-frequency transformation unit.

In one embodiment, as shown in fig. 5, a circuit diagram of a dc high voltage generating apparatus is provided, where the dc voltage doubling unit 140 includes N cascaded voltage doubling circuits 140N, an input terminal of a first stage voltage doubling circuit is connected to the high frequency transforming unit 130, an input terminal of an mth stage voltage doubling circuit is correspondingly connected to an output terminal of an m-1 th stage voltage doubling circuit, and the nth stage voltage doubling circuit is used for outputting dc high voltage, where 1 < m ≦ N, and m and N are positive integers. Specifically, in the embodiment shown in fig. 5, the dc voltage doubling unit 140 includes 2 voltage doubling circuits 140N in cascade.

The circuit can output positive polarity direct current high voltage, and the output voltage value can be improved under the condition of changing the whole topology by increasing the cascade number of the voltage doubling circuit. Meanwhile, the voltage-multiplying circuit topological structure also has potential of being applied to a low-voltage electronic circuit, and provides voltage with a stable preset voltage value for the low-voltage electronic circuit.

In one embodiment, the voltage-withstand values of the voltage-doubling circuits during normal operation are the same, and the highest operating voltage is the voltage value output by the secondary side of the high-frequency transformation unit, which is beneficial to the design of the insulation of the high-voltage generation device.

In one embodiment, continuing with fig. 5, voltage doubler circuit 140N comprises: a first capacitor C1, a second capacitor C2, a third capacitor C3, a fifth diode D5, a sixth diode D6, a seventh diode D7, and an eighth diode D8. One end of the first capacitor C1 is used as a first input port; the cathode of the fifth diode D5 is connected with the first capacitor; the anode of the sixth diode D6 is connected to the anode of the fifth diode D5; wherein a node between the fifth diode D5 and the sixth diode D6 serves as a second input port; one end of the second capacitor C2 is connected to the cathode of the sixth diode D6, and the other end serves as a third input port; the anode of the seventh diode D7 is connected to the cathode of the fifth diode D5; the cathode of the eighth diode D8 is connected with the cathode of the seventh diode D7, and the anode of the eighth diode D8 is connected with the cathode of the sixth diode; a node at which the anode of the seventh diode D7 is connected to the cathode of the fifth diode D5 serves as a first output port; the connection point of the seventh diode D7 and the eighth diode D8 serves as a second output port; a node at which the anode of the eighth diode D8 is connected to the cathode of the sixth diode D6 serves as a third output port; the third capacitor C3 is connected to the anode of the fifth diode D5 and the cathode of the seventh diode D7, respectively.

In one embodiment, the highest withstand voltage of each diode and each capacitor in the voltage doubling circuit is the same and is 10 kV.

At present, in a voltage doubling circuit of a high-voltage direct-current generating device, the requirement on the withstand voltage of each capacitor and diode is high, and the capacitance value of a high-voltage capacitor for high-voltage and high-current application cannot reach high withstand voltage, so that the problems of low transient response speed, large ripple factor, large volume and the like of the direct-current high-voltage generating device designed by the traditional voltage doubling circuit are caused. Therefore, the direct-current voltage generating device in the circuit provided by the invention has low requirement on voltage resistance of each device, high response speed and low voltage signal drop, and can bring great convenience to the development of an insulation test of a power system.

In one embodiment, the high-frequency transforming unit includes two output ports, a first input port of the first stage voltage-doubling circuit is connected with the first output port of the high-frequency transforming unit, a second input port is used for grounding, and a third input port is connected with the second output port of the high-frequency transforming unit.

In one embodiment, the second output port of the nth stage voltage doubling circuit is used for connecting a load.

In one embodiment, each input end of the mth stage voltage doubling circuit is correspondingly connected with each output end of the (m-1) th stage voltage doubling circuit, namely, a first input end of the mth stage voltage doubling circuit is connected with a first output end of the (m-1) th stage voltage doubling circuit, a second input end of the mth stage voltage doubling circuit is connected with a second output end of the (m-1) th stage voltage doubling circuit, and a third input end of the mth stage voltage doubling circuit is connected with a third output end of the (m-1) th stage voltage doubling circuit.

In one embodiment, the preset voltage value is n times of the voltage value of the second ac signal. Namely, each stage of voltage doubling circuit can increase the voltage value to 1 time of the peak value of the output voltage signal at the high-voltage side of the high-frequency transformation unit, and the voltage doubling circuit is cascaded n times to output the direct-current high voltage meeting the requirement, wherein the value of the direct-current high voltage can reach nUac, n is the number of cascade connection, and Uac is the output voltage signal at the secondary side of the high-frequency transformation unit.

In one embodiment, the high frequency transforming unit 130 is a high frequency transformer, and the transformation ratio of the transformer is 310V: 8kV, and the working frequency of the transformer is 10 kHz.

In one embodiment, as shown in fig. 5, a circuit diagram of a dc high voltage generator is provided, which includes the electronic components in the above embodiments, wherein the connection relationship of the electronic components is as defined above, and is not described herein again.

The power frequency power supply of the system is 220V commercial power, the filter capacitor is charged after rectification by the rectifying circuit, and after the system is connected with the power supply, the voltage on the filter capacitor is stabilized at the voltageBecause the capacitance value of the capacitor for aluminum electrolysis is large, the ripple coefficient of the voltage signal is small. After the high-frequency inversion unit consisting of 4 IGBT modules with anti-parallel diodes inverts, a first alternating current signal can be input to the primary side of the high-frequency transformation unit, after the high-frequency transformation unit boosts the voltage through the high-frequency transformer, a second alternating current signal is output to the secondary side, and the main frequency of the high-frequency high voltage is the same as the frequency of the high-frequency inversion unit.

In one embodiment, as shown in fig. 6, a schematic diagram for charging two third capacitors in the voltage doubling circuit at positive half cycle of the high frequency ac signal is provided. When the high frequency transformation unit outputs a positive half cycle of the voltage signal, the seventh diode D7₁Sixth diode D6₁Seventh diode D7₂And a sixth diode D6₂On and the other diodes off. In this case, the high frequency transformer 130 and the first capacitor C1 are used in the first stage voltage doubling circuit₁Is a third capacitor C3₁And a second capacitor C2₁The voltage value of the supplementary charge will increase. For the second stage voltage-doubling circuit, the high-frequency voltage transformation unit 130 and the first capacitor C1 are used₂Is its third capacitance C3₂And a second capacitor C2₂The charge is replenished and its voltage value increases. The above process makes the third capacitor C3₁And a third capacitor C3₂Second capacitor C2₁And a second capacitor C2₂The voltage value of the high-frequency transformation unit can be maintained at the peak value of the output voltage signal of the high-frequency transformation unit.

In one embodiment, as shown in FIG. 7, it is provided that the high frequency transformer outputs the negative half cycle of the voltage signalAnd charging the third capacitor. When the high frequency transformation unit outputs a negative half cycle of the voltage signal, the fifth diode D5₁An eighth diode D8₁An eighth diode D8₂And a seventh diode D7₂On and the other diodes off. In this case, the high frequency transformer 130 and the second capacitor C2 are used for the first stage voltage doubling circuit₁Is a third capacitor C3₁And a first capacitor C1₁The voltage value of the supplementary charge will increase. For the second stage voltage-doubling circuit, the high-frequency voltage transformation unit 130 and the second capacitor C2 are used₂Is its third capacitance C3₂And a first capacitor C1₂The charge is replenished and its voltage value increases. The above process makes the third capacitor C3₁And C3₂First capacitor C1₁And a first capacitor C1₂The voltage value of the high-frequency voltage transformation unit is maintained at the peak value of the voltage signal output by the high-frequency voltage transformation unit.

In one embodiment, a third capacitor discharge circuit schematic is provided, as shown in FIG. 8. When the third capacitor is charged in the positive and negative half cycles, all the diodes are in the cut-off state. At this time, if the second output terminal of the voltage doubling circuit is connected to the load, the third capacitor C3₁And a third capacitor C3₂The load will be discharged and the voltage value of the third capacitor will gradually decrease.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.