Novel IGBT drive circuit

Abstract

The utility model discloses a novel IGBT (Insulated Gate Bipolar Translator) driving circuit, which comprises a driving signal control module, a grid voltage monitoring and logic processing module and a triode driving and resistance switching module, the grid voltage monitoring and logic processing module comprises a grid voltage, a first signal comparator and a second signal comparator which are connected with the grid voltage, a turn-on threshold voltage connected with the first signal comparator, a Miller platform voltage connected with the second signal comparator, and a gate voltage monitoring and logic processing module connected with the turn-on threshold voltage and the Miller platform voltage. The logic gate circuit is connected with the first signal comparator and the second signal comparator; the triode driving and resistor switching module comprises a turn-on triode group, a turn-on resistor assembly connected with the turn-on triode group, a turn-off triode group, and a turn-off resistor assembly connected with the turn-off triode group. The IGBT is quickly turned on and reliably turned off, and the dead time is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a novel IGBT drive circuit. Background Art

[0002] IGBT is a power semiconductor device, also known as insulated gate bipolar transistor, which is a core device for energy conversion and transmission; IGBT drive circuit is the key part to ensure that IGBT can work correctly and stably. The drive circuit provides the correct gate drive signal for the IGBT to control its on and off; the on or off resistance of the traditional IGBT drive circuit is usually a fixed resistance value. Considering the insulation and EMC characteristics of the motor winding, the voltage change slope dVce / dt of the IGBT collector-emitter is not high, and the voltage change slope dVce / dt of the IGBT collector-emitter is affected by the gate resistance of the IGBT.

[0003] Prior art, CN219697485U, an IGBT drive circuit, includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a chip U, a bootstrap voltage stabilization filter module and a drive module, one end of the resistor R1 is connected to one end of the resistor R2 and the No. 2 pin of the chip U, the other end of the resistor R2 is grounded, one end of the resistor R3 is connected to one end of the resistor R4 and the No. 3 pin of the chip U, the other end of the resistor R4 is grounded, and the No. 4 pin of the chip U is grounded. The utility model IGBT drive circuit simplifies the logic circuit and improves the system reliability, adopts the bootstrap voltage stabilization filter module to provide a stable power supply, and allows the single-chip microcomputer to directly drive the chip U, and directly connects the PWM signal output by the single-chip microcomputer to the resistor R1 and the resistor R3, thereby reducing the volume and the number of power supplies, simplifying the system structure and improving the system reliability. However, the prior art also has the following defects: 1. The fixed gate resistance will affect the voltage change slope dVce / dt of the IGBT collector-emitter, making it unable to quickly reach the ideal switching speed; 2. The switching process before the threshold voltage and after the Miller voltage is relatively slow, requiring a larger dead time to prevent the upper and lower tubes from being directly turned on, further reducing the response performance of the control system.

[0004] Therefore, it is necessary to improve the IGBT driving circuit in the prior art to solve the above problems. Summary of the invention

[0005] The utility model overcomes the shortcomings of the prior art and provides a novel IGBT drive circuit, aiming to solve the problem in the prior art that the fixed gate resistance affects the change rate of the collector-emitter voltage, resulting in a reduction in switching speed, and a larger dead time is required to prevent the upper and lower tubes from being directly connected.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a novel IGBT drive circuit, comprising: a drive signal control module, a gate voltage monitoring and logic processing module connected to the drive signal control module, and a transistor drive and resistance switching module connected to the gate voltage monitoring and logic processing module, characterized in that;

[0007] The driving signal control module comprises: a driving signal, a signal input interface for receiving the driving signal;

[0008] The gate voltage monitoring and logic processing module includes: a gate voltage, a first signal comparator and a second signal comparator connected to the gate voltage, a turn-on threshold voltage connected to the first signal comparator, a Miller platform voltage connected to the second signal comparator, and a logic gate circuit connected to the first signal comparator and the second signal comparator;

[0009] The transistor driving and resistance switching module includes: an on-transistor group, an on-resistance component connected to the on-transistor group, an off-transistor group, and an off-resistance component connected to the off-transistor group.

[0010] In a preferred embodiment of the utility model, the logic gate circuit includes: a first NOR gate connected to the first signal comparator and the second signal comparator, a NAND gate connected to the first NOR gate and the drive signal, a NOT gate connected to the drive signal, an XNOR gate connected to the NOT gate and the first NOR gate, and a second NOR gate connected to the XNOR gate and the drive signal.

[0011] In a preferred embodiment of the utility model, the turn-on transistor group includes: a second turn-on transistor and a third turn-on transistor; the turn-on resistor component includes: a second turn-on resistor and a fourth turn-on resistor; the second turn-on transistor is connected to the second turn-on resistor, and the third turn-on transistor is connected to the fourth turn-on resistor.

[0012] In a preferred embodiment of the utility model, the shutdown transistor group includes: a first shutdown transistor and a fourth shutdown transistor; the shutdown resistor component includes: a third shutdown resistor and a fifth shutdown resistor; the first shutdown transistor is connected to the third shutdown resistor, and the fourth shutdown transistor is connected to the fifth shutdown resistor.

[0013] In a preferred embodiment of the present invention, the turn-on transistor group is connected to a sixth resistor.

[0014] In a preferred embodiment of the present invention, the shut-off transistor group is connected to a seventh resistor.

[0015] In a preferred embodiment of the present invention, the driving signal is connected to a first resistor.

[0016] The utility model solves the defects existing in the background technology, and has the following beneficial effects:

[0017] (1) The utility model realizes fast turn-on and reliable turn-off of IGBT through precise signal control and coordination of multiple transistors and resistors, improves switching speed, reduces dead time, and enhances the response performance of the control system. At the same time, dVce / dt is improved by dynamically adjusting the gate resistance, solving the problems caused by fixed gate resistance in the prior art.

[0018] (2) The utility model utilizes a drive signal control module to receive and process a drive signal, and is combined with a gate voltage monitoring and logic processing module. In the step, the signal processed by the drive signal control module is connected to the gate voltage monitoring and logic processing module. The module receives the drive signal from the drive signal control module and the gate voltage of the IGBT, and further realizes rapid switching and reliable switching by generating a control signal. Compared with the prior art, the switching speed and the response performance of the system are improved.

[0019] (3) The utility model uses a signal comparator and a logic gate circuit through a gate voltage monitoring and logic processing module to effectively control the switching state of the transistor and achieve precise voltage control. Compared with the dVce / dt problem caused by fixed resistance in the prior art, the voltage change slope is improved and the switching loss is reduced by dynamically adjusting the gate resistance.

[0020] (4) The transistor drive and resistor switching module of the utility model indirectly controls the gate voltage change of the IGBT by controlling the switch of the transistor. By using a combination of multiple transistors and resistors, the gate resistance is dynamically adjusted, the switching speed is improved, the required dead time is reduced, and the direct conduction of the upper and lower tubes is prevented.

[0021] (5) The logic gate circuit of the utility model is combined with a signal comparator to accurately control the switching state of the transistor. Through the combination of the logic gate circuit, the transistor is avoided from being mistakenly turned on or off under inappropriate voltage conditions, thereby improving the reliability and stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments;

[0023] Figure 1 It is an on-off circuit diagram of a preferred embodiment of the utility model;

[0024] Figure 2 It is a control signal circuit diagram of a preferred embodiment of the utility model;

[0025] Figure 3It is a diagram of the opening simulation result of the preferred embodiment of the utility model;

[0026] Figure 4 It is a shutdown simulation result diagram of a preferred embodiment of the utility model;

[0027] In the figure: 1, second turn-on resistor; 2, fourth turn-on resistor; 3, second turn-on transistor; 4, third turn-on transistor; 5, driving signal; 6, gate voltage; 7, first turn-off transistor; 8, fourth turn-off transistor; 9, third turn-off resistor; 10, fifth turn-off resistor; 11, turn-on threshold voltage; 12, Miller platform voltage; 13, first NOR gate; 14, NAND gate; 15, first signal comparator; 16, second signal comparator; 17, NOT gate; 18, XOR gate; 19, second NOR gate. DETAILED DESCRIPTION

[0028] The present invention will now be further described in detail in conjunction with the accompanying drawings and embodiments. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0029] like Figure 1 As shown, a novel IGBT drive circuit includes: a drive signal control module, a gate voltage monitoring and logic processing module connected to the drive signal control module, and a transistor drive and resistance switching module connected to the gate voltage monitoring and logic processing module;

[0030] The drive signal control module is responsible for receiving and processing the drive signal 5, and connecting the processed signal to the gate voltage monitoring and logic processing module. The gate voltage monitoring and logic processing module receives the drive signal 5 from the drive signal control module and the gate voltage 6 obtained from the IGBT, and connects the generated control signal including the turn-on signal Vo_on and the turn-off signal Vo_off to the transistor drive and resistance switching module. The transistor drive and resistance switching module indirectly controls the change of the gate voltage 6 of the IGBT by controlling the switch of the transistor, thereby achieving fast turn-on and reliable turn-off.

[0031] The driving signal control module includes: a driving signal 5 and a signal input interface for receiving the driving signal 5; the driving signal 5 is connected to a first resistor.

[0032] The transistor driving and resistance switching module includes: an on transistor group, an on resistance component connected to the on transistor group, an off transistor group, and an off resistance component connected to the off transistor group;

[0033] The turn-on transistor group includes: a second turn-on transistor 3 and a third turn-on transistor 4; the turn-on resistor component includes: a second turn-on resistor 1 and a fourth turn-on resistor 2; the second turn-on transistor 3 is connected to the second turn-on resistor 1, and the third turn-on transistor 4 is connected to the fourth turn-on resistor 2; the turn-on transistor group is connected to the sixth resistor.

[0034] The second turn-on transistor 3 has the same function as a commonly used turn-on circuit. When the drive signal 5 becomes a high level, the second turn-on transistor 3 is turned on. Before the gate voltage 6 of the IGBT reaches the turn-on threshold and after the Miller voltage, the third turn-on transistor 4 is turned on, so that the IGBT is turned on faster without affecting the switching speed of the IGBT.

[0035] The turn-off transistor group includes: a first turn-off transistor 7 and a fourth turn-off transistor 8; the turn-off resistor component includes: a third turn-off resistor 9 and a fifth turn-off resistor 10; the first turn-off transistor 7 is connected to the third turn-off resistor 9, and the fourth turn-off transistor 8 is connected to the fifth turn-off resistor 10; the turn-off transistor group is connected to the seventh resistor.

[0036] When the driving signal 5 becomes low, the first turn-off transistor 7 is turned on, and the gate charge is discharged through the third turn-off resistor 9. When the gate voltage 6 is lower than the threshold voltage and the gate voltage 6 is greater than the Miller voltage, the fourth turn-off transistor 8 is turned on, and the gate charge can be discharged through the fifth turn-off resistor 10.

[0037] The new IGBT drive circuit can dynamically adjust the gate resistance by using a combination of multiple transistors and resistors, thereby improving dVce / dt and solving the problems caused by fixed gate resistance in the prior art. Due to the increase in switching speed, the new circuit can reduce the required dead time, which helps prevent the upper and lower tubes from being directly connected, while improving the response performance of the control system.

[0038] The gate voltage monitoring and logic processing module includes: a gate voltage 6, a first signal comparator 15 and a second signal comparator 16 connected to the gate voltage 6, a turn-on threshold voltage 11 connected to the first signal comparator 15, a Miller platform voltage 12 connected to the second signal comparator 16, and a logic gate circuit connected to the first signal comparator 15 and the second signal comparator 16;

[0039] like Figure 2 The control signals of the transistor shown, the turn-on signal Vo_on and the turn-off signal Vo_off, are composed of a drive signal 5, a comparison signal between the gate voltage 6 and the turn-on threshold voltage 11, and a comparison signal between the gate voltage 6 and the Miller platform voltage 12, which are controlled by a logic gate circuit; by using a signal comparator and a logic gate circuit, the switching state of the transistor can be effectively controlled to achieve precise voltage control, which is of great significance for improving the switching speed of power electronic devices and reducing switching losses.

[0040] The logic gate circuit includes: a first NOR gate 13 connected to a first signal comparator 15 and a second signal comparator 16, a NAND gate 14 connected to the first NOR gate 13 and a drive signal 5, a NOT gate 17 connected to the drive signal 5, an XNOR gate 18 connected to the NOT gate 17 and the first NOR gate 13, and a second NOR gate 19 connected to the XNOR gate 18 and the drive signal 5.

[0041] like Figure 3 The simulation diagram of the opening process is as follows:

[0042] (1) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is less than the turn-on threshold voltage 11, the first signal comparator 15 outputs a high level. When the gate voltage 6 is less than the Miller platform voltage 12, the second signal comparator 16 outputs a low level. The output of the first NOR gate 13 is a low level. At this time, the driving signal 5 is at a high level during the rising period. The output signal of the first NOR gate 13 passes through the NAND gate 14. The NAND gate 14 outputs a high level. At this time, the turn-on signal Vo_on is a high level, and the third turn-on transistor 4 is turned on;

[0043] (2) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is greater than the turn-on threshold voltage 11, the first signal comparator 15 outputs a low level. When the gate voltage 6 is less than the Miller platform voltage 12, the second signal comparator 16 outputs a low level. After passing through the first NOR gate 13, the output is a high level. At this time, the driving signal 5 is at a high level during the rising period. The output signal of the first NOR gate 13 passes through the NAND gate 14, and the NAND gate 14 outputs a low level. At this time, the turn-on signal Vo_on is a low level, and the third turn-on transistor 4 is turned off;

[0044] (3) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is greater than the turn-on threshold voltage 11, the first signal comparator 15 outputs a low level. When the gate voltage 6 is greater than the Miller platform voltage 12, the second signal comparator 16 outputs a high level. The output is a low level after passing through the first NOR gate 13. At this time, the driving signal 5 is at a high level during the rising period. The output signal of the first NOR gate 13 passes through the NAND gate 14. The NAND gate 14 outputs a high level. At this time, the turn-on signal Vo_on is a high level, and the third turn-on transistor 4 is turned on.

[0045] The signal control of the turn-on process can accurately control the turn-on timing of the transistor by comparing the gate voltage 6 with the turn-on threshold voltage 11 and the Miller platform voltage 12. When the gate voltage 6 reaches a certain condition, a turn-on signal can be quickly generated to speed up the turn-on speed of the transistor. At the same time, through the combination of logic gate circuits, the transistor can be avoided from being mistakenly turned on under inappropriate voltage conditions.

[0046] like Figure 4This is a simulation diagram of the shutdown process. The shutdown process is as follows:

[0047] (1) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is greater than the turn-on threshold voltage 11, the first signal comparator 15 outputs a low level. When the gate voltage 6 is greater than the Miller platform voltage 12, the second signal comparator 16 outputs a high level. After passing through the first NOR gate 13, the output is a low level. At this time, the driving signal 5 is at a low level during the off period. The output of the NOR gate 17 is a high level. The output signal of the first NOR gate 13 passes through the XOR gate 18. The XOR gate 18 outputs a high level. After the XOR gate 18 and the low level of the driving signal 5 pass through the second NOR gate 19, the second NOR gate 19 outputs a low level. At this time, the off signal Vo_off is a low level, and the fourth off transistor 8 is turned on.

[0048] (2) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is greater than the turn-on threshold voltage 11, the first signal comparator 15 outputs a low level. When the gate voltage 6 is less than the Miller platform voltage 12, the second signal comparator 16 outputs a low level. After passing through the first NOR gate 13, the output is a high level. At this time, the driving signal 5 is at a low level during the off period. The output of the NOR gate 17 is a high level. The output signal of the first NOR gate 13 passes through the XOR gate 18. The XOR gate 18 outputs a low level. After the XOR gate 18 and the low level of the driving signal 5 pass through the second NOR gate 19, the output of the second NOR gate 19 is a high level. At this time, the off signal Vo_off is a high level, and the fourth off transistor 8 is turned off.

[0049] (3) The gate voltage 6 is compared with the turn-on threshold voltage 11. When the gate voltage 6 is less than the turn-on threshold voltage 11, the first signal comparator 15 outputs a high level. When the gate voltage 6 is less than the Miller platform voltage 12, the second signal comparator 16 outputs a low level. After passing through the first NOR gate 13, the output is a low level. At this time, the driving signal 5 is at a low level during the off period. The output of the NOR gate 17 is a high level. The output signal of the first NOR gate 13 passes through the XOR gate 18. The XOR gate 18 outputs a high level. After the XOR gate 18 and the low level of the driving signal 5 pass through the second NOR gate 19, the second NOR gate 19 outputs a low level. At this time, the off signal Vo_off is a low level, and the fourth off transistor 8 is turned on.

[0050] The signal control of the shutdown process ensures that the transistor can be safely shut down when the gate voltage 6 is lower than the turn-on threshold voltage 11, preventing malfunction due to voltage instability, and by accurately controlling the shutdown timing, the energy loss of the transistor during the shutdown process can be reduced.

[0051] The utility model realizes the rapid opening and reliable closing of the IGBT through precise signal control and the coordination of multiple transistors and resistors. The IGBT circuit includes a drive signal 5 control module, a gate voltage 6 monitoring and logic processing module and a transistor drive and resistance switching module; in the opening process, by comparing the gate voltage 6 with the threshold voltage and the Miller platform voltage 12, the logic gate circuit is used to accurately control the conduction timing of the transistor to accelerate the switching speed; in the closing process, it is ensured that the gate voltage 6 is safely closed when it is lower than the threshold, thereby reducing false operations and energy losses; by dynamically adjusting the gate resistance, dVce / dt is improved, the switching speed is increased, the dead time is reduced, and the response performance of the control system is enhanced.

[0052] The above is based on the ideal embodiment of the utility model. Through the above description, relevant personnel can make various changes and modifications without deviating from the technical concept of the utility model. The technical scope of this utility model is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A novel IGBT drive circuit, comprising: A drive signal control module, a gate voltage monitoring and logic processing module connected to the drive signal control module, and a transistor drive and resistance switching module connected to the gate voltage monitoring and logic processing module, characterized in that; The driving signal control module comprises: a driving signal (5), a signal input interface for receiving the driving signal (5); The gate voltage monitoring and logic processing module comprises: a gate voltage (6), a first signal comparator (15) and a second signal comparator (16) connected to the gate voltage (6), a turn-on threshold voltage (11) connected to the first signal comparator (15), a Miller platform voltage (12) connected to the second signal comparator (16), and a logic gate circuit connected to the first signal comparator (15) and the second signal comparator (16); The transistor driving and resistance switching module includes: an on-transistor group, an on-resistance component connected to the on-transistor group, an off-transistor group, and an off-resistance component connected to the off-transistor group.

2. A novel IGBT driving circuit according to claim 1, characterized in that: The logic gate circuit comprises: a first NOR gate (13) connected to the first signal comparator (15) and the second signal comparator (16), a NAND gate (14) connected to the first NOR gate (13) and the drive signal (5), a NOT gate (17) connected to the drive signal (5), an XNOR gate (18) connected to the NOT gate (17) and the first NOR gate (13), and a second NOR gate (19) connected to the XNOR gate (18) and the drive signal (5).

3. A novel IGBT driving circuit according to claim 1, characterized in that: The on-triode group comprises: a second on-triode (3) and a third on-triode (4); the on-resistance component comprises: a second on-resistance (1) and a fourth on-resistance (2); the second on-triode (3) is connected to the second on-resistance (1), and the third on-triode (4) is connected to the fourth on-resistance (2).

4. The novel IGBT driving circuit according to claim 1 is characterized in that: The turn-off transistor group comprises: a first turn-off transistor (7) and a fourth turn-off transistor (8); the turn-off resistor component comprises: a third turn-off resistor (9) and a fifth turn-off resistor (10); the first turn-off transistor (7) is connected to the third turn-off resistor (9), and the fourth turn-off transistor (8) is connected to the fifth turn-off resistor (10).

5. The novel IGBT driving circuit according to claim 1 is characterized in that: The turn-on transistor group is connected to a sixth resistor.

6. The novel IGBT driving circuit according to claim 1 is characterized in that: The turn-off transistor group is connected to the seventh resistor.

7. The novel IGBT driving circuit according to claim 1 is characterized in that: The driving signal (5) is connected to the first resistor.

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