Advanced driving circuit for high-frequency power supply

Abstract

The utility model discloses an advanced driving circuit for a high-frequency power supply, which relates to the technical field of high-frequency power supplies and comprises a main circuit, a control circuit, a driving circuit positioned between the main circuit and the control circuit, and an intermediate circuit for amplifying signals of the control circuit, a power supply of an interface board in the driving circuit is isolated by a conjugate transformer and then is electrically connected with the IGBT. After a pulse signal optical fiber receiving head receives a signal, a push-pull circuit composed of a resistor R1, a triode Q1 and a triode Q2 outputs a pulse driving signal to trigger an IGBT (Insulated Gate Bipolar Translator) to drive a PWM1; similarly, after passing through a push-pull circuit composed of a resistor R2, a triode Q3 and a triode Q4, a pulse driving signal is output to trigger an IGBT to drive a PWM2. By adopting the mode, the push-pull circuit has the effects of improving power output, reducing distortion, enhancing driving capability and improving switching speed and load capacity, and effectively solves the problems that most of the existing driving circuits are extremely easy to interfere and low in safety and stability.

Description

Technical Field

[0001] The utility model relates to the technical field of high-frequency power supply, in particular to an advanced driving circuit for high-frequency power supply. Background Art

[0002] As the scale of human production expands, air pollution becomes more serious. Dust is one of the main pollutants causing air pollution. Coal processing, mining, electricity, metallurgy, oil refining, chemical industry, papermaking and other industries are all sources of dust emissions. At present, electrostatic precipitators can effectively reduce the emission of dust in industrial production, and the recovered dust contains a large amount of precious materials such as metals, thereby effectively reducing the loss of a large amount of precious metal materials.

[0003] At present, most of the electrostatic precipitator power supplies used in my country are powered by industrial frequency power supplies, which have obvious disadvantages such as low dust removal efficiency, high energy consumption, low power factor, and long response time. High-frequency and high-voltage electrostatic precipitator power supplies overcome the disadvantages of industrial frequency switching power supplies. They can provide almost flat corona voltage and fast response time, and have obvious advantages such as high dust removal efficiency, small resistance loss, high temperature resistance, and large flue gas treatment capacity. Therefore, they have good application prospects. However, because the core of high-frequency and high-voltage switching power supplies is an inverter circuit using IGBT as a switching device, most of the existing IGBT drive circuits in high-power switching power supply applications have the disadvantages of being extremely susceptible to interference, low security and stability. Utility Model Content

[0004] The purpose of the utility model is to provide an advanced driving circuit for a high-frequency power supply to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] An advanced driving circuit for high-frequency power supply, comprising a main circuit, a control circuit, a driving circuit located between the main circuit and the control circuit, and an intermediate circuit for amplifying the control circuit signal, wherein the power supply of the interface board in the driving circuit is electrically connected to the IGBT after isolating the power supply through a conjugate transformer, and the high-frequency fault signal of the IGBT is fed back to the control circuit through an optical fiber;

[0007] The interface board in the driving circuit includes a push-pull circuit 1 composed of a resistor R1, a transistor Q1, and a transistor Q2, and a push-pull circuit 2 composed of a resistor R2, a transistor Q3, and a transistor Q4. The push-pull circuit 1 outputs a pulse driving signal to trigger the IGBT to drive PWM1, and the push-pull circuit 2 outputs a pulse driving signal to trigger the IGBT to drive PWM2. An interlocking protection circuit is electrically connected between the output end of PWM1 and the output end of PWM2.

[0008] Preferably, the interlock protection circuit comprises a light emitting diode LED1 connected from the output end of PWM2 to the output end of PWM1, a resistor R3, a resistor R4 and a transistor Q5.

[0009] Preferably, the interlock protection circuit further includes a light emitting diode LED2 connected from the output end of PWM1 to the output end of PWM2, a resistor R5, a resistor R6 and a transistor Q6.

[0010] Preferably, the pulse control signal in the control circuit is connected to the optical fiber receiving head end of the high-frequency driving board of the intermediate circuit via the optical fiber transmitting head end, and the optical fiber transmitting and receiving head end of the high-frequency driving board is connected to the optical fiber receiving head end of the high-frequency power supply controller of the control circuit through the high-frequency fault signal optical fiber.

[0011] Preferably, the high-frequency fault signal forms an IGBT fault circuit through transistor Q7, resistor R7 and the optical fiber transmitter, and is received by the signal optical fiber and the optical fiber receiving head and then input into the high-frequency power supply controller.

[0012] Preferably, the control circuit is provided with two optical fiber transmitting heads and the high-frequency driving board optical fiber receiving heads are provided with two heads respectively, and the two optical fiber transmitting heads in the control circuit are connected to the two optical fiber receiving heads of the high-frequency driving board through the high-frequency A group driving optical fiber and the high-frequency B group driving optical fiber respectively.

[0013] Preferably, the transistor Q1 and the transistor Q3 both adopt PNP polarity.

[0014] Preferably, the transistor Q2, the transistor Q4, the transistor Q5 and the transistor Q6 all adopt NPN polarity.

[0015] Due to the adoption of the above technical solution, the utility model has achieved the following technical progress compared with the prior art:

[0016] The utility model provides an advanced driving circuit for high-frequency power supply, in order to solve the problem that most of the IGBT driving circuits in existing high-power switching power supply applications are extremely susceptible to interference, low security and stability. After receiving the signal through the pulse signal optical fiber receiving head, the push-pull circuit 1 composed of resistor R1, transistor Q1 and transistor Q2 outputs a pulse driving signal to trigger the IGBT drive PWM1; similarly, after receiving the signal through the push-pull circuit 2 composed of resistor R2, transistor Q3 and transistor Q4, the pulse signal optical fiber receiving head outputs a pulse driving signal to trigger the IGBT drive PWM2; the push-pull circuit 1 and the push-pull circuit 2 adopt this method to improve power output, reduce distortion, enhance driving ability, and improve switching speed and load capacity, effectively solving the problem that most of the existing driving circuits are extremely susceptible to interference, low security and stability.

[0017] The utility model provides an advanced driving circuit for high-frequency power supply, in which an IGBT pulse control signal is sent through a high-frequency power supply controller through two optical fiber transmitting heads, and is connected to an optical fiber receiving head on a high-frequency driving board through optical fibers, thereby achieving the purpose of completely isolating the control pulse driving signal from the IGBT, and an IGBT fault signal is formed into an IGBT fault circuit through a transistor Q7, a resistor R7 and an optical fiber transmitting head, and is received by the optical fiber and the receiving optical fiber head, and then input into a high-frequency controller, thereby achieving the purpose of completely isolating all IGBT signals.

[0018] The utility model provides an advanced driving circuit for a high-frequency power supply, wherein a PWM2 output terminal is connected to a PWM1 output terminal via a light-emitting diode LED1, a resistor R3, a resistor R4, and a transistor Q5; when the PWM2 output terminal is at a high level, the PWM1 output terminal is forced to be pulled low; similarly, for the sake of safety, the PWM1 output terminal is connected to the PWM2 output terminal via a light-emitting diode LED2, a resistor R5, a resistor R6, and a transistor Q6; when the PWM1 output terminal is at a high level, the PWM2 output terminal is forced to be pulled low, thereby realizing the function of interlocking the output signals PWM1 and PWM2. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the circuit of the utility model;

[0020] Figure 2 This is a schematic diagram of the principle circuit structure of the interface board in the drive circuit.

[0021] In the figure: 1. driving circuit; 2. main circuit; 3. control circuit; 4. conjugate transformer. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below in conjunction with the embodiments:

[0023] like Figure 1-2As shown, the utility model provides an advanced driving circuit for high-frequency power supply, including a main circuit 2, a control circuit 3, a driving circuit 1 located between the main circuit 2 and the control circuit 3, and an intermediate circuit for amplifying the signal of the control circuit 3. The driving circuit 1 has the function of amplifying the PWM pulse of the control electrical output to a power amplification function sufficient to drive the power transistor-switch power. The power supply of the interface board in the driving circuit 1 is electrically connected to the IGBT after isolating the power supply through a conjugate transformer 4. The high-frequency fault signal of the IGBT is fed back to the control circuit 3 through an optical fiber. The interface board in the driving circuit 1 is electrically connected to the IGBT through an optical fiber. The board includes a push-pull circuit 1 composed of a resistor R1, a transistor Q1, and a transistor Q2, and a push-pull circuit 2 composed of a resistor R2, a transistor Q3, and a transistor Q4. The push-pull circuit 1 outputs a pulse drive signal to trigger the IGBT to drive PWM1, and the push-pull circuit 2 outputs a pulse drive signal to trigger the IGBT to drive PWM2. An interlocking protection circuit is electrically connected between the output end of PWM1 and the output end of PWM2. The transistors Q1 and Q3 both adopt PNP polarity, and the transistors Q2, Q4, Q5, and Q6 all adopt NPN polarity.

[0024] like Figure 2 As shown, specifically, after a pulse signal 1 in an optical fiber receiving head receives a signal, it passes through a push-pull circuit 1 composed of a resistor R1 and transistor Q1 (PNP) and transistor Q1Q2 (NPN) to output a pulse drive signal to trigger the IGBT to drive PWM1; similarly, after a pulse signal 1 in another optical fiber receiving head receives a signal, it passes through a push-pull circuit 2 composed of a resistor R2 and transistor Q3 (PNP) and transistor Q4 (NPN) to output a pulse drive signal to trigger the IGBT to drive PWM2. The push-pull circuit 1 and the push-pull circuit 2 use this method to improve power output, reduce distortion, enhance driving capability, and improve switching speed and load capacity.

[0025] like Figure 2 As shown, the interlock protection circuit includes a light-emitting diode LED1 connected from the output end of PWM2 to the output end of PWM1, a resistor R3, a resistor R4 and a transistor Q5, and the interlock protection circuit also includes a light-emitting diode LED2 connected from the output end of PWM1 to the output end of PWM2, a resistor R5, a resistor R6 and a transistor Q6.

[0026] Specifically, in order to ensure that the IGBT is not damaged and PWM1 and PWM2 cannot be turned on at the same time, an interlocking protection circuit is required. The function implementation principle of the interlocking protection circuit is as follows: the output end of PWM2 is connected to the output end of PWM1 through a light-emitting diode LED1, a resistor R3, a resistor R4, and a transistor Q5 (NPN); when the output end of PWM2 is at a high level, the output end of PWM1 is forced to be pulled low; similarly, for the sake of safety, the output end of PWM1 is connected to the output end of PWM2 through a light-emitting diode LED2, a resistor R5, a resistor R6, and a transistor Q6 (NPN); when the output end of PWM1 is at a high level, the output end of PWM2 is forced to be pulled low, thereby realizing the function of interlocking the output signals PWM1 and PWM2.

[0027] like Figure 1 As shown, the pulse control signal in the control circuit 3 is connected to the high-frequency driving board optical fiber receiving head end of the intermediate circuit via the optical fiber transmitting head end, and the optical fiber transmitting and receiving head end of the high-frequency driving board is connected to the optical fiber receiving head end of the high-frequency power supply controller of the control circuit 3 via the high-frequency fault signal optical fiber. The high-frequency fault signal forms an IGBT fault circuit through the transistor Q7, the resistor R7 and the optical fiber transmitting head, and is received by the signal optical fiber and the optical fiber receiving head and then input into the high-frequency power supply controller. There are two optical fiber transmitting heads and two optical fiber receiving heads of the high-frequency driving board in the control circuit 3, and the two optical fiber transmitting heads in the control circuit 3 are respectively connected to the two optical fiber receiving heads of the high-frequency driving board through the high-frequency A group driving optical fiber and the high-frequency B group driving optical fiber.

[0028] Specifically, the high-frequency power supply controller sends the IGBT pulse control signal through two optical fiber transmitters, which are connected to the optical fiber receiving head on the high-frequency drive board through optical fibers, thereby achieving the purpose of completely isolating the control pulse drive signal from the IGBT. Similarly, the IGBT fault signal is fed back to the high-frequency controller through the optical fiber, and the IGBT fault signal forms an IGBT fault circuit through the transistor Q7, the resistor R7 and the optical fiber transmitter. After being received by the optical fiber and the receiving optical fiber head, it is input into the high-frequency controller, thereby achieving the purpose of completely isolating all IGBT signals.

[0029] It should be pointed out that in the description of the present disclosure, it should be explained that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0030] The above generally describes the present invention in detail, but it is obvious to a person skilled in the art that some modifications or improvements can be made to the present invention. Therefore, modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. An advanced driving circuit for a high frequency power supply, characterized in that: It includes a main circuit, a control circuit, a drive circuit between the main circuit and the control circuit, and an intermediate circuit for amplifying the control circuit signal. The power supply of the interface board in the drive circuit is electrically connected to the IGBT after isolating the power supply through a conjugate transformer, and the high-frequency fault signal of the IGBT is fed back to the control circuit through an optical fiber. The interface board in the driving circuit includes a push-pull circuit 1 composed of a resistor R1, a transistor Q1, and a transistor Q2, and a push-pull circuit 2 composed of a resistor R2, a transistor Q3, and a transistor Q4. The push-pull circuit 1 outputs a pulse driving signal to trigger the IGBT to drive PWM1, and the push-pull circuit 2 outputs a pulse driving signal to trigger the IGBT to drive PWM2. An interlocking protection circuit is electrically connected between the output end of PWM1 and the output end of PWM2.

2. The advanced driving circuit for high frequency power supply according to claim 1, characterized in that: The interlock protection circuit includes a light emitting diode LED1 connected from the output end of PWM2 to the output end of PWM1, a resistor R3, a resistor R4 and a transistor Q5.

3. The advanced driving circuit for high frequency power supply according to claim 2, characterized in that: The interlock protection circuit further includes a light emitting diode LED2 connected from the output end of PWM1 to the output end of PWM2, a resistor R5, a resistor R6 and a transistor Q6.

4. The advanced driving circuit for high frequency power supply according to claim 1, characterized in that: The pulse control signal in the control circuit is connected to the optical fiber receiving head end of the high-frequency driving board of the intermediate circuit via the optical fiber transmitting head end, and the optical fiber transmitting and receiving head end of the high-frequency driving board is connected to the optical fiber receiving head end of the high-frequency power supply controller of the control circuit through the high-frequency fault signal optical fiber.

5. The advanced driving circuit for high frequency power supply according to claim 4, characterized in that: The high-frequency fault signal is transmitted through the transistor Q7, the resistor R7 and the optical fiber transmitting head to form an IGBT fault circuit, and is received by the signal optical fiber and the optical fiber receiving head and then input into the high-frequency power supply controller.

6. The advanced driving circuit for high frequency power supply according to claim 4, characterized in that: The control circuit is provided with two optical fiber transmitting heads and the high-frequency driving board optical fiber receiving heads are provided with two heads respectively, and the two optical fiber transmitting heads in the control circuit are connected to the two optical fiber receiving heads of the high-frequency driving board through the high-frequency A group driving optical fiber and the high-frequency B group driving optical fiber respectively.

7. The advanced driving circuit for high frequency power supply according to claim 3, characterized in that: The transistor Q1 and the transistor Q3 both adopt PNP polarity.

8. The advanced driving circuit for high frequency power supply according to claim 7, characterized in that: The transistors Q2 , Q4 , Q5 and Q6 all adopt NPN polarity.

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