Protection circuit and IGBT drive control module of intelligent variable frequency constant current power supply

Abstract

This application relates to a protection circuit for an intelligent variable frequency constant current power supply, comprising several sub-circuits. The IGBT drive control module includes a collector, a drive chip, and a gate. The sub-circuits include a resistor, diodes 1, 2, 3, 4, 5, 6, and 7, and a capacitor. The resistor, diodes 1 and 2 are connected in series. The end of the resistor furthest from diode 1 is the first connection terminal, used to connect to the DES pin of the drive chip. One end of the capacitor connected in parallel with diode 7 is connected to the first connection terminal, and the other end is grounded. The end of diode 2 furthest from diode 1 is the second connection terminal, used to connect to the collector. One end of diodes 6, 3, 4, and 5 connected in series is connected to the second connection terminal, and the other end is connected to the gate. The protection circuit of this application is less prone to failure and is beneficial for the long-term stable operation of the IGBT drive control module.

Description

Technical Field

[0001] This application relates to the field of variable frequency constant current power supply technology, and in particular to a protection circuit and IGBT drive control module for an intelligent variable frequency constant current power supply. Background Technology

[0002] A high-frequency, high-voltage DC power supply is a device used to generate high-frequency, high-voltage power. It typically includes a transformer, rectifier, filter, and power amplifier, with output voltages reaching thousands or even tens of kilovolts and output frequencies ranging from thousands to hundreds of hertz. The basic principle of a high-frequency, high-voltage power supply is to utilize the interaction of components such as inductors, capacitors, and switching transistors in the circuit to generate a high-frequency oscillation circuit, which is then used to boost the voltage through a transformer. When the input voltage oscillates at a high frequency, the switching transistor rapidly switches the output circuit, causing the inductor to store energy and transfer it to the output terminal; at the output terminal, the capacitor releases the stored energy to form a high-voltage output.

[0003] For example, Chinese patent application number CN201310096035.5 discloses a frequency converter power supply, including a control module and a power supply module electrically connected to the control module. The control module is also electrically connected to a rectifier circuit, a protection circuit, a detection circuit, and an IGBT drive circuit. The rectifier circuit is also electrically connected to the output terminal of the power supply module. The IGBT drive circuit is also electrically connected to an IGBT switching circuit. The protection circuit includes a surge protection circuit, an overcurrent protection circuit, an overvoltage protection circuit, and an overtemperature protection circuit. The surge protection circuit, overcurrent protection circuit, overvoltage protection circuit, and overtemperature protection circuit are respectively connected to the input terminal of the control module.

[0004] Regarding the aforementioned technologies, the inventors believe that the following defects exist: the protection circuit of a common variable frequency constant current power supply has four sub-circuit modules with completely different functional structures, and uses a large number of electronic components, which makes it easy to fail and is not conducive to the long-term stable operation of the control module. Utility Model Content

[0005] This application provides a protection circuit and IGBT drive control module for an intelligent variable frequency constant current power supply to improve the following technical problems: the protection circuit of a common variable frequency constant current power supply has many sub-circuit modules and uses many electronic components, which are prone to failure and are not conducive to the long-term stable operation of the control module.

[0006] In a first aspect, this application provides a protection circuit for an intelligent variable frequency constant current power supply, which adopts the following technical solution:

[0007] A protection circuit for an intelligent variable frequency constant current power supply includes several sub-circuits that connect to and protect an IGBT drive control module. The IGBT drive control module includes a collector, a drive chip, and a gate. Each sub-circuit includes a resistor, diodes 1, 2, 3, 4, 5, 6, and 7, and a capacitor. The resistor, diode 1, and diode 2 are connected in series. The end of the resistor furthest from diode 1 is a first connection terminal, which is used to connect to the DES pin of the drive chip. One end of the capacitor connected in parallel with diode 7 is connected to the first connection terminal, and the other end is grounded. The end of diode 2 furthest from diode 1 is a second connection terminal, which is used to connect to the collector. One end of diodes 6, 3, 4, and 5 connected in series is connected to the second connection terminal, and the other end is used to connect to the gate.

[0008] In one feasible technical solution of this application, the sub-circuit has two components. The IGBT drive control module includes an upper transistor circuit and a lower transistor circuit. The upper transistor circuit has a collector IGBT1, a first driver chip, and a gate OUT1. One of the sub-circuits is used to connect to and protect the upper transistor circuit from desaturation voltage. The lower transistor circuit has a collector IGBT2, a second driver chip, and a gate OUT2. The other sub-circuit is used to connect to and protect the lower transistor circuit from desaturation voltage.

[0009] In one feasible technical solution of this application, the diode five is a bidirectional breakdown diode.

[0010] In one feasible technical solution of this application, diode seven, diode three, and diode four are all single tunnel diodes.

[0011] In one feasible technical solution of this application, diode one, diode two, and diode six are all rectifier diodes.

[0012] In one feasible technical solution of this application, the cathode of diode seven is connected to the DES pin of the driver chip, and the cathode of diode six is ​​connected to the gate.

[0013] Secondly, this application provides an IGBT drive control module, which adopts the following technical solution: an IGBT drive control module, including: an input / output interface circuit, a DC power conversion circuit, an isolation power supply circuit, an isolation drive circuit, a single-chip microcomputer (MCU) unit circuit, and the protection circuit as described above.

[0014] In one feasible technical solution of this application, the input / output interface circuit is used to complete the level conversion and filtering of the input control pulse and the level conversion and filtering of the alarm signal; the DC power conversion circuit is used to convert the input 15V DC voltage into a stable and low-ripple 5V and 12V voltage; the isolation power supply circuit is used to convert the 12V DC voltage into an isolated +15V and -9V voltage; the microcontroller (MCU) unit circuit is used to complete the signal processing and control functions of the entire system, the control functions including generating corresponding control signals according to the input pulse, configuring and controlling the isolation drive circuit, and completing the identification and processing of alarm signals; the isolation drive circuit is used to complete the signal isolation and drive functions according to the configuration and control signals of the MCU, enabling the IGBT drive control module to work according to the signal and provide alarm signals according to the working status.

[0015] In summary, this application includes at least one of the following beneficial technical effects:

[0016] To protect the IGBT drive control module from desaturation voltage, resistor, diode 1, and diode 2 are connected in series and then connected to the collector and the DES pin of the drive chip, respectively. When the IGBT drive control module enters the desaturation state, diodes 1 and 2 will change from the conducting state to the cutoff state. The drive chip will detect this change and output a corresponding control signal to shut down the IGBT drive control module, thereby protecting the IGBT drive control module. Resistor, capacitor, and diode 7 are used to protect the DSE pin of the drive chip and filter out interference signals to avoid malfunction of the protection.

[0017] To protect against voltage spikes between the collector and gate of the IGBT drive control module, diodes six, three, four, and five are connected in series to the collector and gate respectively. When the voltage spike between the collector and gate of the IGBT drive control module exceeds the protection voltage threshold, diodes six, three, four, and five will change from the off state to the on state, limiting the voltage between the collector and gate within a safe voltage range and absorbing the energy of the voltage spike. Diode five is a bidirectional breakdown diode with stable voltage-temperature characteristics and small inter-electrode capacitance, which facilitates the cooperation of diodes six, three, four, and five to break it down.

[0018] The protection circuit of this application has the same functional structure for each sub-circuit module, and uses a relatively small number and variety of electronic components. This not only ensures good protection effect, but also makes it less prone to failure, which is conducive to the long-term stable operation of the IGBT drive control module. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of one of the sub-circuits in the protection circuit of this application embodiment.

[0021] Figure 2 This is a schematic diagram of another sub-circuit in the protection circuit of this application embodiment.

[0022] Figure 3 This is a schematic diagram of the IGBT drive control module according to an embodiment of this application.

[0023] Explanation of reference numerals in the attached figures:

[0024] R, Resistor; C, Capacitor; D1, Diode 1; D2, Diode 2; D3, Diode 3; D4, Diode 4; D5, Diode 5; D6, Diode 6; D7, Diode 7. Detailed Implementation

[0025] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0026] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0027] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0029] The following is in conjunction with the appendix Figure 1-3 This application will be further described in detail below. An embodiment of this application discloses a protection circuit for an intelligent variable frequency constant current power supply. (Refer to...) Figure 1 and Figure 2 The protection circuit of the intelligent variable frequency constant current power supply includes several sub-circuits that connect to and protect the IGBT drive control module. The IGBT drive control module includes a collector, a drive chip, and a gate. The sub-circuit includes a resistor R, diodes D1, D2, D3, D4, D5, D6, D7, and a capacitor C. Resistor R, diodes D1 and D2 are connected in series. The end of resistor R furthest from diode D1 is the first connection terminal, which is used to connect to the DES pin of the drive chip. One end of capacitor C connected in parallel with diode D7 is connected to the first connection terminal, and the other end is grounded. The end of diode D2 furthest from diode D1 is the second connection terminal, which is used to connect to the collector. One end of diodes D6, D3, D4, and D5 connected in series is connected to the second connection terminal, and the other end is used to connect to the gate.

[0030] In this embodiment, there are two sub-circuits. The IGBT drive control module includes an upper transistor circuit and a lower transistor circuit. The upper transistor circuit has a collector IGBT1, a first driver chip, and a gate OUT1. One sub-circuit is used to connect to and protect the upper transistor circuit from desaturation voltage. The lower transistor circuit has a collector IGBT2, a second driver chip, and a gate OUT2. Another sub-circuit is used to connect to and protect the lower transistor circuit from desaturation voltage.

[0031] Among them, diode 5D5 is a bidirectional breakdown diode, diode 7D7, diode 3D3, and diode 4D4 are all single tunnel diodes, diode 1D1, diode 2D2, and diode 6D6 are all rectifier diodes, the cathode of diode 7D7 is connected to the DES pin of the driver chip, and the cathode of diode 6D6 is connected to the gate.

[0032] Reference Figure 3 This application also discloses an IGBT drive control module, including: an input / output interface circuit, a DC power conversion circuit, an isolation power supply circuit, an isolation drive circuit, a microcontroller (MCU) unit circuit, and a protection circuit as described above.

[0033] The input / output interface circuit is used to perform level conversion and filtering of input control pulses and alarm signals; the DC power conversion circuit is used to convert the input 15V DC voltage into stable and low-ripple 5V and 12V voltages; the isolation power supply circuit is used to convert the 12V DC voltage into isolated +15V and -9V voltages; the microcontroller (MCU) unit circuit is used to perform signal processing and control functions for the entire system, including generating corresponding control signals based on input pulses, configuring and controlling the isolation drive circuit, and identifying and processing alarm signals; the isolation drive circuit is used to perform signal isolation and drive functions based on the MCU's configuration and control signals, enabling the IGBT drive control module to operate according to signals and providing alarm signals based on the operating status.

[0034] The beneficial technical effects of the protection circuit and IGBT drive control module of the intelligent variable frequency constant current power supply in this application embodiment are roughly as follows:

[0035] To protect the IGBT drive control module from desaturation voltage, resistor R, diode D1, and diode D2 are connected in series and then connected to the collector and the DES pin of the drive chip, respectively. When the IGBT drive control module enters the desaturation state, diodes D1 and D2 will change from the on state to the off state. The drive chip will detect this change and output a corresponding control signal to shut down the IGBT drive control module, thereby protecting the IGBT drive control module. Resistor R, capacitor C, and diode D7 are used to protect the DSE pin of the drive chip and filter out interference signals to avoid false protection operation.

[0036] To protect against voltage spikes between the collector and gate of the IGBT drive control module, diodes D6, D3, D4, and D5 are connected in series to the collector and gate respectively. When the voltage spike between the collector and gate of the IGBT drive control module exceeds the protection voltage threshold, diodes D6, D3, D4, and D5 will change from the off state to the on state, limiting the voltage between the collector and gate within a safe voltage range and absorbing the energy of the voltage spike. Furthermore, diode D5 is a bidirectional breakdown diode with stable voltage-temperature characteristics and a small inter-electrode capacitance C, which facilitates the cooperation of diodes D6, D3, D4, and D5 to break it down.

[0037] The protection circuit of this application has the same functional structure for each sub-circuit module, and uses a relatively small number and variety of electronic components. This not only ensures good protection effect, but also makes it less prone to failure, which is conducive to the long-term stable operation of the IGBT drive control module.

[0038] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A protection circuit of an intelligent variable frequency constant current power supply, characterized in that, The device includes several sub-circuits that connect and protect an IGBT drive control module. The IGBT drive control module includes a collector, a drive chip, and a gate. Each sub-circuit includes a resistor (R), diodes 1 (D1), 2 (D2), 3 (D3), 4 (D4), 5 (D5), 6 (D6), 7 (D7), and a capacitor (C). The resistor (R), diodes 1 (D1), and 2 (D2) are connected in series. The end of the resistor (R) furthest from diode 1 (D1) is the first connection terminal, which is used to connect to the DES pin of the drive chip. One end of the capacitor (C) connected in parallel with diode 7 (D7) is connected to the first connection terminal, and the other end is grounded. The end of diode 2 (D2) furthest from diode 1 (D1) is the second connection terminal, which is used to connect to the collector. One end of diodes 6 (D6), 3 (D3), 4 (D4), and 5 (D5) connected in series is connected to the second connection terminal, and the other end is used to connect to the gate.

2. The protection circuit of the intelligent variable-frequency constant-current power supply according to claim 1, characterized in that, The sub-circuit has two components. The IGBT drive control module includes an upper transistor circuit and a lower transistor circuit. The upper transistor circuit has a collector IGBT1, a first driver chip, and a gate OUT1. One of the sub-circuits is used to connect to and protect the upper transistor circuit from desaturation voltage. The lower transistor circuit has a collector IGBT2, a second driver chip, and a gate OUT2. The other sub-circuit is used to connect to and protect the lower transistor circuit from desaturation voltage.

3. The protection circuit of the intelligent variable frequency constant current power supply according to claim 1, characterized in that, The diode five (D5) is a bidirectional breakdown diode.

4. The protection circuit of the intelligent variable-frequency constant-current power supply according to claim 1, characterized in that, Diode 7 (D7), Diode 3 (D3), and Diode 4 (D4) are all single tunnel diodes.

5. The protection circuit of the intelligent variable frequency constant current power supply according to claim 1, characterized in that, Diode 1 (D1), Diode 2 (D2), and Diode 6 (D6) are all rectifier diodes.

6. The protection circuit of the intelligent variable-frequency constant-current power supply according to claim 1, characterized in that, The cathode of diode seven (D7) is connected to the DES pin of the driver chip, and the cathode of diode six (D6) is connected to the gate.

7. An IGBT drive control module, characterized by, include: Input / output interface circuit, DC power conversion circuit, isolation power supply circuit, isolation drive circuit, microcontroller (MCU) unit circuit, and protection circuit as described in any one of claims 1-6.

8. The IGBT drive control module of claim 7, wherein, The input / output interface circuit is used to perform level conversion and filtering of input control pulses and level conversion and filtering of alarm signals; the DC power conversion circuit is used to convert the input 15V DC voltage into stable and low-ripple 5V and 12V voltages; the isolation power supply circuit is used to convert the 12V DC voltage into isolated +15V and -9V voltages; the microcontroller (MCU) unit circuit is used to perform signal processing and control functions for the entire system, including generating corresponding control signals based on input pulses, configuring and controlling the isolation drive circuit, and identifying and processing alarm signals. The isolation driving circuit is used for completing signal isolation and driving functions according to the configuration and control signals of the MCU, making the IGBT driving control module work according to signals and providing an alarm signal according to a working state.

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