MOS / IGBT driving circuit giving driving current in real time according to target driving waveform

Abstract

The invention discloses an MOS / IGBT (Metal Oxide Semiconductor / Insulated Gate Bipolar Transistor) driving circuit for giving a driving current in real time according to a target driving waveform, and relates to the technical field of MOS / IGBT driving control, comprising a PWM (Pulse Width Modulation) signal generation module for generating an original PWM signal; the delay circuit module is used for delaying the original PWM signal to obtain a target driving waveform with a target switching speed; the operational amplifier negative feedback circuit module comprises an input positive electrode, an input negative electrode and an output pin, the input positive electrode is used for accessing a target driving waveform, the input negative electrode is connected with a grid electrode of the MOS / IGBT device, and the output pin is connected with an input end of the current driving circuit module; and a target driving waveform is compared and amplified by the operational amplifier negative feedback circuit module and is subjected to current amplification by the current driving circuit module to drive the MOS / IGBT device. According to the invention, all power tubes in the system can have consistent switching speed, and even power tubes of different models can be driven to have consistent waveforms, so that the efficiency and stability of the whole system are improved.

Description

Technical Field

[0001] This invention relates to the technical field of MOS / IGBT drive control, and in particular to a MOS / IGBT drive circuit that provides a drive current in real time based on a target drive waveform. Background Technology

[0002] MOS / IGBT drive control refers to the technology of controlling the switching of two types of power semiconductor devices, MOS (Metal-Oxide-Semiconductor Field-Effect Transistor) and IGBT (Insulated Gate Bipolar Transistor), using voltage-driven methods. Both MOS and IGBT are voltage-controlled devices, and their drive control principle is to change the internal electric field strength by altering the gate voltage, thereby regulating the current flow.

[0003] Existing MOS / IGBT drive control circuits suffer from unstable drive waveforms and inconsistent switching speeds due to interference caused by factors such as parameter differences between different batches of MOS / IGBT power devices, individual parameter differences between different power devices within the same batch, and stray inductance and capacitance in the circuit. Summary of the Invention

[0004] This invention provides a MOS / IGBT driving circuit that provides a driving current in real time based on the target driving waveform. It solves the problems of unstable driving waveform and inconsistent switching speed caused by interference from factors such as parameter differences between different batches of MOS / IGBT power devices, individual parameter differences between different power devices in the same batch, and stray inductance and capacitance of the circuit.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a MOS / IGBT driving circuit that provides a driving current in real time based on a target driving waveform, comprising a PWM signal generation module, a delay circuit module, an operational amplifier negative feedback circuit module, and a current driving circuit module connected in sequence; the output terminal of the current driving circuit module is connected to the gate of the MOS / IGBT device to be driven. The PWM signal generation module is used to generate the original PWM signal; The delay circuit module is used to delay the original PWM signal to obtain a target drive waveform with the target switching speed; The operational amplifier negative feedback circuit module includes an input positive terminal, an input negative terminal, and an output pin. The input positive terminal is used to connect to the target driving waveform, the input negative terminal is connected to the gate of the MOS / IGBT device, and the output pin is connected to the input terminal of the current driving circuit module. The target driving waveform is sequentially compared and amplified by the operational amplifier negative feedback circuit module, and then amplified by the current driving circuit module to drive the MOS / IGBT device.

[0006] In one possible implementation, the operational amplifier negative feedback circuit module includes an operational amplifier; The positive input of the operational amplifier is used to connect to the target driving waveform, the negative input of the operational amplifier is connected to the gate of the MOS / IGBT device, and the output pin of the operational amplifier is connected to the input terminal of the current driving circuit module.

[0007] In one possible implementation, the operational amplifier negative feedback circuit module further includes a first resistor and a filter capacitor; The first resistor is connected in series between the negative input terminal of the operational amplifier and the gate of the MOS / IGBT device; the filter capacitor is connected in series between the positive and negative power supply terminals of the operational amplifier.

[0008] In one possible implementation, the current drive circuit module is a totem circuit or a driver chip for driving MOS / IGBT devices.

[0009] In one possible implementation, the delay circuit module is an RC delay circuit, including a second resistor and a first capacitor; One end of the second resistor is connected to the PWM signal generation module, and the other end of the second resistor is connected to one end of the first capacitor and the positive input of the operational amplifier negative feedback circuit module. The other end of the first capacitor is grounded.

[0010] In one possible implementation, a third resistor is connected in series between the output of the current drive circuit module and the gate of the MOS / IGBT device to be driven.

[0011] In one possible implementation, the PWM signal generation module is a PWM chip, an MCU, or a signal generator.

[0012] In one possible implementation, when the PWM signal generation module is an AC signal generator, it also includes a clamping diode; The clamping diode is connected in parallel with the first capacitor, and the positive terminal of the clamping diode is grounded.

[0013] In practical applications, the MOS / IGBT driving circuit provided by this invention, which provides real-time driving current based on the target driving waveform, allows users to set the required original PWM signal through the PWM signal generation module. The original PWM signal is then delayed by the delay circuit module to obtain the target driving waveform with the desired switching speed. The target driving waveform is amplified by the operational amplifier negative feedback circuit module and the current driving circuit module, and the driving current is adjusted in real time to make the level of each point of the MOS / IGBT device to be driven infinitely close to the target driving waveform. This ensures that all power transistors in the multi-transistor parallel circuit have a consistent switching speed, and even different types of MOS / IGBT devices can be driven to the same waveform, thereby improving the efficiency and stability of the entire multi-transistor parallel circuit system. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a MOS / IGBT driving circuit that provides real-time driving current based on a target driving waveform, according to an embodiment of the present invention. Figure 2 A circuit diagram of a MOS / IGBT driving circuit that provides real-time driving current based on a target driving waveform, provided for an embodiment of the present invention; Figure 3 This invention provides a signal setting diagram for a PWM signal generation module in a MOS / IGBT drive circuit that provides real-time drive current based on a target drive waveform, according to an embodiment of the present invention. Figure 4 A signal waveform diagram of point A in a MOS / IGBT driving circuit that provides real-time driving current based on a target driving waveform, provided in an embodiment of the present invention; Figure 5 The above is a signal waveform diagram of point B and point C in a MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform, as provided in an embodiment of the present invention.

[0015] Figure labels and descriptions: 1. PWM signal generation module; 2. Delay circuit module; 3. Operational amplifier negative feedback circuit module; 4. Current drive circuit module; 5. MOS / IGBT devices. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Hereinafter, 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, the use of "based on" or "according to" implies openness and inclusiveness, because processes, steps, calculations, or other actions "based on" or "according to" one or more of the stated conditions or values ​​may in practice be based on additional conditions or beyond the stated values.

[0018] To address the issues of unstable drive waveforms and inconsistent switching speeds caused by parameter differences between different batches of MOS / IGBT power devices, individual parameter differences between different power devices within the same batch, and interference caused by stray inductance and capacitance in the circuit, this invention provides a MOS / IGBT drive circuit that provides a real-time drive current based on the target drive waveform.

[0019] like Figure 1 As shown, this embodiment of the invention provides a MOS / IGBT driving circuit that provides a driving current in real time according to a target driving waveform. It includes a PWM signal generation module 1, a delay circuit module 2, an operational amplifier negative feedback circuit module 3, and a current driving circuit module 4 connected in sequence. The output terminal of the current driving circuit module 4 is connected to the gate of the MOS / IGBT device 5 to be driven.

[0020] PWM signal generation module 1 is used to generate the original PWM signal.

[0021] The PWM signal generation module 1 can generate the original PWM signal using hardware methods such as a 555 timer circuit, a dedicated PWM chip, and an operational amplifier triangular wave comparator circuit. It can also generate the original PWM signal using microcontroller software or through programmable logic devices (such as FPGA or CPLD).

[0022] The delay circuit module 2 is used to delay the original PWM signal to obtain the target drive waveform with the target switching speed.

[0023] The delay circuit module 2 applies a controllable delay to the original PWM signal to generate a target drive waveform that meets the driving requirements. For example, in applications such as industrial control, motor drive, and LED dimming, the original PWM signal often cannot directly drive power devices (MOS or IGBT). A delay circuit is needed to adjust the edge time or pulse width of the signal to meet the switching characteristics of the power device (such as turn-on or turn-off delay) and application requirements (such as dead-time control or duty cycle accuracy adjustment).

[0024] Furthermore, the delay circuit module 2 can be implemented using digital delay chains (such as inverters, D flip-flops, dedicated delay units, etc., multi-level delay units connected in series), programmable delays (such as switches, counters, memories, etc., configurable elements to adjust the delay time), RC delay circuits, and hybrid delays using both digital and analog methods (such as digital delay chains for coarse adjustment and RC delay circuits for fine adjustment).

[0025] The operational amplifier negative feedback circuit module 3 includes an input positive terminal, an input negative terminal, and an output pin. The input positive terminal is used to connect to the target driving waveform, the input negative terminal is connected to the gate of the MOS / IGBT device 5, and the output pin is connected to the input terminal of the current driving circuit module 4. The target driving waveform is compared and amplified by the operational amplifier negative feedback circuit module 3, and then amplified by the current driving circuit module 4 to drive the MOS / IGBT device 5.

[0026] The operational amplifier negative feedback circuit collects the output current at the output terminal, performs differential calculation with the input current received at the input terminal, and feeds the result back to the input terminal, thereby regulating the input current. When the input current changes, the feedback signal changes the magnitude of the input current, forming a closed-loop control. The current drive circuit module 4 can be a totem circuit or a professional driver chip, used to amplify the output current of the operational amplifier negative feedback circuit.

[0027] In this embodiment, after the original PWM signal is processed by the delay circuit module 2 to obtain the target drive waveform with the target switching speed required by the user, the operational amplifier negative feedback circuit adjusts the drive current in real time according to the target waveform, so that the MOS / IGBT device 5 to be driven can achieve the ideal gate drive waveform. The ideal gate drive waveform approximates the target drive waveform infinitely.

[0028] In practical applications, the MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform provided in this embodiment of the invention allows users to set the required original PWM signal through the PWM signal generation module 1. The original PWM signal is delayed by the delay circuit module 2 to obtain the target driving waveform with the target switching speed required by the user. The target driving waveform is compared and amplified by the operational amplifier negative feedback circuit module 3 and the current amplification by the current driving circuit module 4, and the driving current is adjusted in real time so that the level of each point of the MOS / IGBT device 5 to be driven is infinitely close to the target driving waveform. This ensures that all power transistors in the multi-transistor parallel circuit have a consistent switching speed, and even different types of MOS / IGBT devices 5 can be driven to the same waveform, thereby improving the efficiency and stability of the entire multi-transistor parallel circuit system.

[0029] In embodiments of the present invention, such as Figure 2 As shown, the operational amplifier negative feedback circuit module further includes operational amplifier U1A.

[0030] The positive input of operational amplifier U1A is used to connect to the target driving waveform, the negative input of operational amplifier U1A is connected to the gate of MOS / IGBT device Q3, and the output pin of operational amplifier U1A is connected to the input terminal of the current driving circuit module.

[0031] Furthermore, the operational amplifier negative feedback circuit module also includes a first resistor R2 and a filter capacitor C2.

[0032] The first resistor R2 is connected in series between the negative input terminal of the operational amplifier U1A and the gate of the MOS / IGBT device Q3; the filter capacitor C2 is connected in series between the positive and negative power supply terminals of the operational amplifier U1A.

[0033] Among them, the first resistor R2 is a current-limiting resistor, and C2 is a power supply filter capacitor.

[0034] In other words, the target driving waveform is input to the positive input of operational amplifier U1A, and the gate driving signal of MOS / IGBT device Q3 is input to the negative input of operational amplifier U1A through the first resistor R2. When the potential of the negative input of operational amplifier U1A is higher than the potential of its positive input, the output pin of operational amplifier U1A outputs a high level to the current driving circuit module for current amplification to increase the driving current. This makes the level of each point of the gate waveform of MOS / IGBT device Q3 infinitely close to the target driving waveform.

[0035] Furthermore, the current drive circuit module is a totem circuit or a driver chip used to drive the MOS / IGBT device Q3.

[0036] The totem circuit consists of a first transistor Q1 and a second transistor Q2. The emitters and bases of the two transistors are connected to form a common collector configuration. During operation, the two transistors conduct alternately. When one transistor enters the saturation region, the other transistor is cut off, thereby achieving bidirectional current drive. The output voltage is the sum of the base voltages of the two transistors.

[0037] The driver chip for the MOS / IGBT device Q3 can be IR2130, IR2109S / STRPBF series, UCC27524DGNR / UCC27710 series, and EG2132 / EG2183D series chips, etc.

[0038] Furthermore, the delay circuit module is an RC delay circuit, including a second resistor R3 and a first capacitor C3.

[0039] One end of the second resistor R3 is connected to the PWM signal generation module, and the other end of the second resistor R3 is connected to one end of the first capacitor C3 and the positive input of the op-amp negative feedback circuit module. The other end of the first capacitor C3 is grounded.

[0040] Furthermore, a third resistor R4 is connected in series between the output terminal of the current drive circuit module and the gate of the MOS / IGBT device Q3 to be driven.

[0041] Furthermore, the PWM signal generation module is a PWM chip, MCU, or signal generator used to set and generate the original PWM signal required by the user.

[0042] Furthermore, when the PWM signal generation module is an AC signal generator, it also includes a clamping diode D1.

[0043] Clamping diode D1 is connected in parallel with the first capacitor C3, and the positive terminal of clamping diode D1 is grounded.

[0044] In this embodiment of the invention, the user-required original PWM signal is set in the PWM signal generation module, such as... Figure 3 As shown, the PWM signal generation module is set to generate a raw PWM signal with a frequency of 100Hz, a duty cycle of 50%, and an amplitude of 12Vp.

[0045] like Figure 2 As shown, the PWM signal waveform at point A in the MOS / IGBT drive circuit of the present invention, which provides real-time drive current based on the target drive waveform, is displayed using the first oscilloscope XSC2; the signal waveforms at points B and C are displayed using the second oscilloscope XSC1. The signal waveform at point A is the original PWM signal generated by the PWM signal generation module; the signal waveform at point B is the target drive waveform after the waveform at point A is delayed by the delay circuit module to set the switching speed; and the signal waveform at point C is the actual drive waveform generated by the gate of the MOS / IGBT device Q3 to be driven following the waveform at point B.

[0046] like Figure 2 , Figure 4 , Figure 5 As shown, the original PWM signal (waveform at point A) generated by the PWM chip, MCU, or signal generator is delayed by an RC delay circuit to set the required switching speed, resulting in the target drive waveform (waveform at point B). The target drive waveform is then amplified by operational amplifier U1A and current amplified by the totem circuit before driving the MOS / IGBT device Q3 through the third resistor R4.

[0047] The target drive waveform (point B waveform) is input to the positive input of operational amplifier U1A, and the drive signal output from the gate of MOS / IGBT device Q3 is input to the negative input of operational amplifier U1A via the first resistor R2. When the potential of the negative input of operational amplifier U1A is lower than that of its positive input, the output pin of operational amplifier U1A outputs a high level to the totem circuit for amplification, increasing the drive current. This ensures that the level of each point in the gate drive waveform of MOS / IGBT device Q3 (point C waveform) approximates the target drive waveform (point B waveform) infinitely. Figure 5 In the diagram, the waveforms at points B and C are completely overlapped in the second oscilloscope XSC1. However, to ensure clearer observation of the waveforms at points B and C, the waveform at point B in the second oscilloscope XSC1 was shifted vertically by 0.2. This means that in practical applications, the changes in the waveforms at points B and C are completely consistent, indicating that the actual drive waveform of the gate of the MOS / IGBT device Q3 follows the changes in the target drive waveform in real time.

[0048] In practical applications, the MOS / IGBT driving circuit of the present invention, which provides real-time driving current based on the target driving waveform, allows users to set the desired target driving waveform as needed, and the target driving waveform can automatically provide the driving current in real time, so that the gate of the MOS / IGBT device Q3 is driven to the switching speed and waveform envelope required by the user.

[0049] The MOS / IGBT drive circuit of the present invention, which provides real-time drive current based on the target drive waveform, is particularly suitable for integrated circuits with high semiconductor device integration, thereby increasing the consistency of driving multiple semiconductor power devices.

[0050] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A MOS / IGBT driving circuit that provides a driving current in real time based on a target driving waveform, characterized in that, It includes a PWM signal generation module, a delay circuit module, an operational amplifier negative feedback circuit module, and a current drive circuit module connected in sequence; the output terminal of the current drive circuit module is connected to the gate of the MOS / IGBT device to be driven. The PWM signal generation module is used to generate the original PWM signal; The delay circuit module is used to delay the original PWM signal to obtain a target drive waveform with the target switching speed; The operational amplifier negative feedback circuit module includes an input positive terminal, an input negative terminal, and an output pin. The input positive terminal is used to connect to the target driving waveform, the input negative terminal is connected to the gate of the MOS / IGBT device, and the output pin is connected to the input terminal of the current driving circuit module. The target driving waveform is sequentially compared and amplified by the operational amplifier negative feedback circuit module, and then amplified by the current driving circuit module to drive the MOS / IGBT device.

2. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 1, characterized in that, The operational amplifier negative feedback circuit module includes an operational amplifier; The positive input of the operational amplifier is used to connect to the target driving waveform, the negative input of the operational amplifier is connected to the gate of the MOS / IGBT device, and the output pin of the operational amplifier is connected to the input terminal of the current driving circuit module.

3. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 2, characterized in that, The operational amplifier negative feedback circuit module also includes a first resistor and a filter capacitor; The first resistor is connected in series between the negative input terminal of the operational amplifier and the gate of the MOS / IGBT device; the filter capacitor is connected in series between the positive and negative power supply terminals of the operational amplifier.

4. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 1, characterized in that, The current drive circuit module is a totem circuit or a drive chip used to drive MOS / IGBT devices.

5. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 1, characterized in that, The delay circuit module is an RC delay circuit, including a second resistor and a first capacitor; One end of the second resistor is connected to the PWM signal generation module, and the other end of the second resistor is connected to one end of the first capacitor and the positive input of the operational amplifier negative feedback circuit module. The other end of the first capacitor is grounded.

6. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 1, characterized in that, A third resistor is connected in series between the output terminal of the current drive circuit module and the gate of the MOS / IGBT device to be driven.

7. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 5, characterized in that, The PWM signal generation module is a PWM chip, MCU, or signal generator.

8. The MOS / IGBT driving circuit that provides real-time driving current based on the target driving waveform according to claim 7, characterized in that, When the PWM signal generation module is an AC signal generator, it also includes a clamping diode; The clamping diode is connected in parallel with the first capacitor, and the positive terminal of the clamping diode is grounded.

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