阅读说明：本技术 一种电力电子器件驱动电源 (Power electronic device driving power supply ) 是由 徐关澄 孟向军 吕淼 王林 吴金龙 于 2021-10-25 设计创作，主要内容包括：本发明一种电力电子器件驱动电源,包括软起网络、控制芯片、功率开关模块、变压器、倍压电路以及输出电路；软起网络连接至控制芯片,在所述控制芯片上电时,所述软起网络电压逐渐升高使得所述控制芯片输出脉冲电压逐渐升高；控制芯片输出脉冲信号,控制所述功率开关模块输出电压至变压器的原边；变压器副边输出电压经倍压电路升压后,由输出电路输出驱动电力电子器件。本发明电路设计简单精巧,保证了驱动电源工作的可靠性。本发明结构简单、成本低、并能提高整个驱动电源的工作性能、安全性和可靠性。(The invention relates to a power electronic device driving power supply which comprises a soft start network, a control chip, a power switch module, a transformer, a voltage doubling circuit and an output circuit, wherein the soft start network is connected with the control chip; the soft start network is connected to the control chip, and when the control chip is powered on, the voltage of the soft start network is gradually increased, so that the output pulse voltage of the control chip is gradually increased; the control chip outputs a pulse signal to control the power switch module to output voltage to the primary side of the transformer; the output voltage of the secondary side of the transformer is boosted by the voltage doubling circuit, and then output by the output circuit drives the power electronic device. The circuit of the invention has simple and exquisite design and ensures the working reliability of the driving power supply. The invention has simple structure and low cost, and can improve the working performance, safety and reliability of the whole driving power supply.)

1. A power electronic device driving power supply is characterized by comprising a soft start network, a control chip, a power switch module, a transformer, a voltage doubling circuit and an output circuit;

the soft start network is connected to a control chip, and when the control chip is powered on, the voltage of the soft start network is gradually increased to enable the control chip to output pulse voltage;

the control chip outputs a pulse signal to control the power switch module to output voltage to the primary side of the transformer;

and after the secondary output voltage of the transformer is boosted by the voltage doubling circuit, the secondary output voltage is output by the output circuit to drive the power electronic device.

2. The power electronics device driver power supply of claim 1, where the control chip is UC 2845.

3. The power electronic device driving power supply according to claim 2, wherein the error amplifier output pin, the error amplifier inverting input pin, and the current detection pin of UC2845 are grounded through a ground resistor; the push-pull output pin outputs the second pulse fixed to be the maximum duty ratio.

4. The power electronics drive power supply according to claim 1 or 2, wherein the soft start network comprises a first diode, a first resistor, and a second diode; the first diode is connected with the first resistor in parallel, the parallel circuit is connected with the voltage-stabilizing capacitor in parallel, a voltage output pin of the control chip is connected with one end of the parallel circuit through the second diode, and the other end of the parallel circuit is connected with a chip reference voltage output pin.

5. The power electronic device driving power supply according to claim 1 or 2, wherein a frequency generating resistor R4 is connected between the chip reference voltage output pin and the frequency oscillation load pin of the control chip, a frequency generating capacitor C3 is connected between the frequency oscillation load pin and the ground pin, and the frequency f of the control chip output pulse is 1.72/(R4C 3).

6. The power electronic device driving power supply according to claim 1 or 2, wherein the power switch module includes an NPN-type transistor, a PNP-type transistor; the collector of the NPN transistor is connected with the anode of a power supply through a pull-up resistor, and the emitter of the NPN transistor is connected with the dotted terminal of the primary side of the transformer and the emitter of the PNP transistor; bases of the NPN type transistor and the PNP type transistor are connected with a pulse output pin of the soft start network through a capacitor and a resistor network which are connected in parallel; and the collector of the PNP transistor is connected to the synonym terminal of the primary side of the transformer through a resistor and a capacitor.

7. The power electronic device driving power supply according to claim 1 or 2, wherein the voltage doubling circuit includes a voltage doubling capacitor, a first voltage doubling diode and a second voltage doubling diode;

one end of the voltage-multiplying capacitor is connected with the different-name end of the secondary side of the transformer, the other end of the voltage-multiplying capacitor is connected with the cathode of the first voltage-multiplying diode, and the anode of the first voltage-multiplying diode is connected with the same-name end of the secondary side of the transformer; the anode of the second voltage doubling diode is connected with the cathode of the first voltage doubling diode, and the cathode of the second voltage doubling diode is connected with the output circuit.

8. The power electronics drive power supply of claim 7 wherein the output circuit includes a zener diode, a bleed resistor, a first support capacitor, and a second support capacitor;

the negative electrode of the voltage stabilizing diode is connected with the negative electrode of the second voltage doubling diode and is used as the positive output end of the driving voltage; the positive electrode of the voltage stabilizing diode is connected with one end of the bleeder resistor and is used as a grounding end of the driving voltage; the other end of the bleeder resistor is connected with the homonymous end of the secondary side of the transformer and is used as a negative output end of the driving voltage; the first support capacitor is connected with the voltage stabilizing diode in parallel, and the second support capacitor is connected with the bleeder resistor in parallel.

Technical Field

The invention relates to the technical field of power supply design, in particular to a power electronic device driving power supply.

Background

Nowadays, with the continuous development of power electronic technology, switching power supplies are widely applied to almost all electronic devices with the characteristics of small size, light weight and high efficiency, and are an indispensable power supply mode for the rapid development of the electronic information industry at present. The high frequency is the development direction, and the high frequency enables the miniaturization of the switching power supply, enables the switching power supply to enter wider application fields, particularly the application in the high and new technology field, and promotes the miniaturization and the lightness of high and new technology products. In addition, the development and application of the switching power supply have important significance in the aspects of security monitoring, energy conservation, resource conservation and environmental protection.

The product is widely applied to the fields of industrial automation control, military equipment, scientific research equipment, LED illumination, industrial control equipment, communication equipment, power equipment, instruments and meters, medical equipment, semiconductor refrigeration and heating, air purifiers, electronic refrigerators, liquid crystal displays, LED lamps, communication equipment, audio-visual products, security monitoring, LED lamp belts, computer cases, digital products, instruments and the like.

The design of the driving power supply is significant for a power electronic device, and the driving power supply with excellent design can reduce the loss of a switching device and ensure the safe and efficient switching-on and switching-off of a switching tube.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides the driving power supply of the power electronic device, the circuit design is simple and exquisite, and the working reliability of the driving power supply is ensured. The invention has simple structure and low cost, and can improve the working performance, safety and reliability of the whole driving power supply.

In order to achieve the above object, the present invention provides a power electronic device driving power supply, which includes a soft start network, a control chip, a power switch module, a transformer, a voltage doubling circuit and an output circuit;

the soft start network is connected to a control chip, and when the control chip is powered on, the voltage of the soft start network is gradually increased to enable the control chip to output pulse voltage;

the control chip outputs a pulse signal to control the power switch module to output voltage to the primary side of the transformer;

and after the secondary output voltage of the transformer is boosted by the voltage doubling circuit, the secondary output voltage is output by the output circuit to drive the power electronic device.

Further, the control chip is UC 2845.

Furthermore, an output pin of the error amplifier of the UC2845, an inverted input pin of the error amplifier, and a current detection pin are grounded through a ground resistor; the push-pull output pin outputs the second pulse fixed to be the maximum duty ratio.

Further, the soft start network comprises a first diode, a first resistor and a second diode; the first diode is connected with the first resistor in parallel, the parallel circuit is connected with the voltage-stabilizing capacitor in parallel, a voltage output pin of the control chip is connected with one end of the parallel circuit through the second diode, and the other end of the parallel circuit is connected with a chip reference voltage output pin.

Furthermore, a frequency generating resistor R4 is connected between the chip reference voltage output pin and the frequency oscillation load pin of the control chip, a frequency generating capacitor C3 is connected between the frequency oscillation load pin and the ground pin, and the frequency f of the output pulse of the control chip is 1.72/(R4C 3).

Further, the power switch module comprises an NPN-type transistor and a PNP-type transistor; the collector of the NPN transistor is connected with the anode of a power supply through a pull-up resistor, and the emitter of the NPN transistor is connected with the dotted terminal of the primary side of the transformer and the emitter of the PNP transistor; bases of the NPN type transistor and the PNP type transistor are connected with a pulse output pin of the soft start network through a capacitor and a resistor network which are connected in parallel; and the collector of the PNP transistor is connected to the synonym terminal of the primary side of the transformer through a resistor and a capacitor.

Further, the voltage doubling circuit comprises a voltage doubling capacitor, a first voltage doubling diode and a second voltage doubling diode;

one end of the voltage-multiplying capacitor is connected with the different-name end of the secondary side of the transformer, the other end of the voltage-multiplying capacitor is connected with the cathode of the first voltage-multiplying diode, and the anode of the first voltage-multiplying diode is connected with the same-name end of the secondary side of the transformer; the anode of the second voltage doubling diode is connected with the cathode of the first voltage doubling diode, and the cathode of the second voltage doubling diode is connected with the output circuit.

Further, the output circuit comprises a voltage stabilizing diode, a bleeder resistor, a first support capacitor and a second support capacitor;

the negative electrode of the voltage stabilizing diode is connected with the negative electrode of the second voltage doubling diode and is used as the positive output end of the driving voltage; the positive electrode of the voltage stabilizing diode is connected with one end of the bleeder resistor and is used as a grounding end of the driving voltage; the other end of the bleeder resistor is connected with the homonymous end of the secondary side of the transformer and is used as a negative output end of the driving voltage; the first support capacitor is connected with the voltage stabilizing diode in parallel, and the second support capacitor is connected with the bleeder resistor in parallel.

The technical scheme of the invention has the following beneficial technical effects:

(1) the circuit of the invention has simple and exquisite design and ensures the working reliability of the driving power supply.

(2) The invention has simple structure and low cost, and can improve the working performance, safety and reliability of the whole driving power supply.

(3) The output of the triode geminate transistor is used for directly driving the on and off of the transformer, and the circuit is simple and easy to debug, so that the reliability is improved.

Drawings

Fig. 1 is a schematic diagram of a control chip UC2845 and its peripheral circuits;

FIG. 2 is a schematic diagram of a secondary side output circuit;

fig. 3 is a schematic diagram of a driving power supply circuit.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

A circuit for driving a power supply is provided, which comprises a soft start network, a control chip, a power switch module, a transformer, a frequency adjusting circuit, a voltage doubling circuit and an output circuit.

The soft start network is connected to a control chip, and when the control chip is powered on, the voltage of the soft start network is gradually increased, so that the output pulse voltage of the control chip is gradually increased.

The soft start network comprises a first diode D2, a first resistor R1, and a second diode D1; the first diode D2 and the first resistor R1 are connected in parallel, the parallel circuit is connected with the voltage-stabilizing capacitors C1 and C2 in parallel, the voltage output pin 14 of the control chip is connected with one end of the parallel circuit through the second diode D1, and the other end of the parallel circuit is connected with the voltage input chip reference voltage output pin 14

The control chip outputs a pulse signal to control the power switch module to output voltage to the primary side of the transformer.

And after the secondary output voltage of the transformer is boosted by the voltage doubling circuit, the secondary output voltage is output by the output circuit to drive the power electronic device.

The frequency adjustment circuit includes a frequency generating resistor R4 and a frequency generating capacitor C3. A frequency generation resistor R4 is connected between a chip reference voltage output pin 14 and a frequency oscillation load pin 7 of the control chip, a frequency generation capacitor C3 is connected between the pin 7 and the pin 8, and the frequency f of an output pulse of the control chip is 1.72/(R4C 3).

The power switch module comprises an NPN transistor Q1 and a PNP transistor Q2; the collector of the NPN transistor Q1 is connected with the positive electrode of a power supply through a pull-up resistor, and the emitter of the NPN transistor Q1 is connected with the dotted terminal of the primary side of the transformer and the emitter of the PNP transistor Q2; the bases of the NPN transistor Q1 and the PNP transistor are connected with a pulse output pin of the soft start network through a capacitor and a resistor network which are connected in parallel; the collector of the PNP transistor Q2 is connected to the synonym terminal of the primary side of the transformer through a resistor and a capacitor.

The voltage doubling circuit comprises a voltage doubling capacitor C6, a first voltage doubling diode D3 and a second voltage doubling diode D4; one end of the voltage-doubling capacitor C6 is connected with the different name end of the secondary side of the transformer T1, the other end of the voltage-doubling capacitor C6 is connected with the cathode D3 of the first voltage-doubling diode, and the anode of the first voltage-doubling diode D3 is connected with the same name end of the secondary side of the transformer T1; the anode of the second voltage doubling diode D4 is connected to the cathode of the first voltage doubling diode D3, and the cathode of the second voltage doubling diode D4 is connected to the output circuit.

The output circuit comprises a voltage stabilizing diode Z1, a bleeder resistor R10, a first supporting capacitor C7 and a second supporting capacitor C8; the cathode of the voltage stabilizing diode Z1 is connected with the cathode of the second voltage doubling diode D4 and is used as the positive output end of the driving voltage; the anode of the voltage stabilizing diode Z1 is connected with one end of the bleeder resistor and is used as the grounding end of the driving voltage; the other end of the bleeder resistor R10 is connected with the dotted terminal of the secondary side of the transformer and is used as the negative output end of the driving voltage; the first supporting capacitor C7 is connected in parallel with the Zener diode Z1, and the second supporting capacitor C8 is connected in parallel with the bleeder resistor R10.

In one embodiment, the control chip UC2845 used is a high-performance single-ended output current control type pulse width modulator chip manufactured by unitede, usa. On the basis of the chip, a control circuit is designed.

The function of each pin of the control chip UC2845 is introduced in table 1.

TABLE 1 UC2845 function of each pin

Referring to fig. 1, a control chip UC2845 and its peripheral circuits are shown, in this embodiment, pins 1, 3 and 5 are directly grounded through a resistor of 10k, a current detection protection function (pin 5) and a voltage feedback detection function (pin 3) of the chip UC2845 are not used, and a compensation circuit (pin 1) of the chip UC2845 is not used. The pins 1, 3 and 5 are grounded, so that the peripheral circuit of the chip can be simplified to the maximum extent, and the debugging process is simplified. In this connection state, the pulse output from the pin of the chip 10 is fixed at the maximum duty ratio (UC2845 is a duty ratio of 50%). And the soft start network composed of the diode, the resistor and the capacitor can enable the circuit to be in soft start, and damage caused by direct maximum duty ratio output is avoided.

In the power-on process, the voltage input pins 11 and 12 of the control chip UC2845 are powered on, and 8 and 9 are grounded pins. The 1 pin output voltage slowly charges the capacitor C2, the 14 pin input voltage gradually increases to start, and the 10 pin output voltage slowly increases with the 14 pin input voltage. After start-up, the voltage at pin 14 is in dynamic equilibrium. The frequency of the 10-pin output pulse varies depending on the values of R4 and C3 between 7 pins and 14 pins, and the frequency f of the 10-pin output pulse is 1.72/(R4 × C3).

In the circuit part shown in fig. 3, the output of the triode geminate transistor is used for directly driving the on-off of the transformer, and the circuit is simple and easy to debug, so that the reliability is improved.

The driving power supply needs to drive different switching tubes, IGBT tubes, MOS field effect tubes, SIC MOS tubes and the like under different working conditions. The driving voltages required by the switching tubes are different, so that the driving power supply is designed to output different voltages to match different switching tubes. The output voltage is adjustable within a range of +/-20V, and the output power is 2-3W. The specific circuit topology is shown in fig. 2:

a voltage doubling circuit formed by a diode and a capacitor is designed, and voltage meeting the output requirement is generated through the voltage doubling circuit. The voltage-stabilizing tube at the rear stage of the circuit can output voltages of different grades by selecting voltage-stabilizing tubes of different models so as to meet the requirement of the circuit for outputting different voltage grades; a bleeder resistor in the circuit generates a backflow branch circuit for driving negative voltage, and the driving negative voltage is ensured not to be increased all the time because of no backflow branch circuit.

In summary, the power electronic device driving power supply of the present invention includes a soft start network, a control chip, a power switch module, a transformer, a voltage doubling circuit, and an output circuit; the soft start network is connected to the control chip, and when the control chip is powered on, the voltage of the soft start network is gradually increased, so that the output pulse voltage of the control chip is gradually increased; the control chip outputs a pulse signal to control the power switch module to output voltage to the primary side of the transformer; the output voltage of the secondary side of the transformer is boosted by the voltage doubling circuit, and then output by the output circuit drives the power electronic device. The circuit of the invention has simple and exquisite design and ensures the working reliability of the driving power supply. The invention has simple structure and low cost, and can improve the working performance, safety and reliability of the whole driving power supply.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.