Isolation type half-bridge IGBT driving power supply

Abstract

The utility model discloses an isolated half-bridge IGBT driving power supply, and relates to the technical field of IGBTs. The circuit comprises a gate drive circuit, an mos tube half-bridge circuit, an isolation transformer, a first rectification circuit and a second rectification circuit. The gate drive circuit is connected with the mos transistor half-bridge circuit, the output end of the mos transistor half-bridge circuit is connected with a primary winding of the isolation transformer, a first winding of a secondary side of the isolation transformer is connected with the first rectifying circuit, and a second winding of the secondary side of the isolation transformer is connected with the second rectifying circuit. The mos tube half-bridge circuit is driven by the gate drive circuit, variable alternating current is provided for the primary winding of the isolation transformer, the alternating current is isolated and transformed by the isolation transformer and then is rectified by the first rectifying circuit to provide a stable drive power supply, and the alternating current is rectified by the second rectifying circuit to provide another stable drive power supply. Therefore, a unified driving power supply capable of driving the parallel IGBTs is provided.

Description

Technical Field

[0001] The utility model relates to the technical field of IGBT, in particular to an isolated half-bridge IGBT driving power supply. Background Art

[0002] High-power energy storage converter units require multiple IGBTs in parallel to achieve capacity expansion. IGBT paralleling involves static and dynamic current sharing of IGBTs. It is crucial to ensure that the driving power supply of the parallel IGBTs is the same. Currently, the power of the IGBT driving power supply can only drive one IGBT, and cannot drive parallel IGBTs. Utility Model Content

[0003] The utility model solves the technical problem of how to drive parallel IGBTs by providing an isolated half-bridge IGBT driving power supply.

[0004] The utility model provides the following technical solutions:

[0005] An isolated half-bridge IGBT driving power supply comprises a gate driving circuit, a MOS tube half-bridge circuit, an isolation transformer, a first rectifier circuit and a second rectifier circuit;

[0006] The gate driving circuit is connected to the MOS tube half-bridge circuit, and the gate driving circuit is used to drive the MOS tube half-bridge circuit;

[0007] The output end of the MOS tube half-bridge circuit is connected to the primary winding of the isolation transformer, and the MOS tube half-bridge circuit is used to supply power to the primary winding of the isolation transformer;

[0008] The first winding of the secondary side of the isolation transformer is connected to the first rectifier circuit, and the second winding of the secondary side of the isolation transformer is connected to the second rectifier circuit.

[0009] Optionally, the isolated half-bridge IGBT drive power supply further includes a current limiting resistor circuit, which is connected in series with the primary winding of the isolation transformer.

[0010] Optionally, the current limiting resistor circuit includes a resistor R11, and the resistor R11 is connected in series with the primary winding of the isolation transformer.

[0011] Optionally, the isolated half-bridge IGBT drive power supply further includes a power supply circuit and a delayed power-on circuit;

[0012] The power supply circuit is connected to the enable terminal of the gate driving circuit via the delayed power-on circuit, and the delayed power-on circuit is used to delay the power-on of the gate driving circuit.

[0013] Optionally, the delayed power-on circuit includes an RC delay circuit, a first transistor switch circuit and a second transistor switch circuit;

[0014] The power supply circuit is connected to the base of the transistor in the first transistor switch circuit via the RC delay circuit, and the first transistor switch circuit outputs a low level when the transistor in the first transistor switch circuit is turned on, and the first transistor switch circuit outputs a high level when the transistor in the first transistor switch circuit is turned off;

[0015] The output end of the first transistor switch circuit is connected to the base of the transistor in the second transistor switch circuit, and the enable end of the gate drive circuit is grounded via the transistor in the second transistor switch circuit.

[0016] Optionally, the RC delay circuit includes a resistor R7 and a capacitor C11;

[0017] The power supply circuit is connected to ground via a resistor R7 and a capacitor C11 in sequence, and a common end of the resistor R7 and the capacitor C11 is connected to the base of the transistor in the first transistor switch circuit.

[0018] Optionally, the RC delay circuit further includes a diode D6, and the diode D6 is connected in reverse parallel with the resistor R7.

[0019] Optionally, the RC delay circuit further includes a voltage stabilizing diode D7, which is reversely connected in series between a common end of the resistor R7 and the capacitor C11 and a transistor base of the first transistor switch circuit.

[0020] Optionally, the first transistor switch circuit includes a resistor R6 and a transistor T3;

[0021] The power supply circuit is connected to the base of transistor T3 via the RC delay circuit. The power supply circuit is also connected to ground via resistor R6 and transistor T3 in sequence. The collector of transistor T3 is the output end of the first transistor switch circuit.

[0022] Optionally, the second transistor switch circuit includes a transistor T2;

[0023] The output end of the first transistor switch circuit is connected to the base of the transistor T2, and the enable end of the gate drive circuit is grounded via the transistor T2.

[0024] The technical solution provided by the utility model has at least the following technical effects or advantages:

[0025] The utility model drives a MOS tube half-bridge circuit through a gate drive circuit to provide a changing alternating current for the primary winding of an isolation transformer. After the alternating current is isolated and transformed by the isolation transformer, it is rectified by a first rectifier circuit to provide a stable driving power supply and rectified by a second rectifier circuit to provide another stable driving power supply, thereby providing a unified driving power supply that can drive parallel IGBTs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 This is a structural block diagram of an isolated half-bridge IGBT drive power supply in an embodiment of the utility model;

[0028] Figure 2 It is a circuit diagram of an isolated half-bridge IGBT driving power supply in an embodiment of the utility model.

[0029] Description of reference numerals:

[0030] 10-gate drive circuit; 20-MOS tube half-bridge circuit; 30-isolation transformer; 40-first rectifier circuit; 50-second rectifier circuit; 60-current limiting resistor circuit; 70-delay power-on circuit; 701-RC delay circuit; 702-first triode switch circuit; 703-second triode switch circuit. DETAILED DESCRIPTION

[0031] The embodiment of the utility model solves the technical problem of how to drive parallel IGBTs by providing an isolated half-bridge IGBT driving power supply.

[0032] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0033] like Figure 1As shown, the isolated half-bridge IGBT drive power supply of the embodiment of the utility model includes a gate drive circuit, a MOS tube half-bridge circuit, an isolation transformer, a first rectifier circuit and a second rectifier circuit; the gate drive circuit is connected to the MOS tube half-bridge circuit, and the gate drive circuit is used to drive the MOS tube half-bridge circuit; the output end of the MOS tube half-bridge circuit is connected to the primary winding of the isolation transformer, and the MOS tube half-bridge circuit is used to power the primary winding of the isolation transformer; the first winding of the secondary side of the isolation transformer is connected to the first rectifier circuit, and the second winding of the secondary side of the isolation transformer is connected to the second rectifier circuit.

[0034] like Figure 2 As shown, the gate drive circuit mainly includes the gate driver U1 and its peripheral circuits. The model of the gate driver U1 can be IRS2153DSTRPBF. The HO of the gate driver U1 is the high-end drive port, the LO is the low-end drive port, and the CT is the enable terminal. By matching the resistance value of the resistor R3 and the capacitance value of the capacitor C7, the drive waveform of the corresponding frequency can be obtained to drive the MOS tube half-bridge circuit. The specific working principle of the gate driver U1 and its peripheral circuits can refer to the chip manual of IRS2153DSTRPBF, which will not be repeated here.

[0035] The MOS tube half-bridge circuit is composed of two N-type MOS tubes. Figure 2 Ports S1, D1, and G1 are the source, drain, and gate of the first MOS tube, respectively. Ports S2, D2, and G2 are the source, drain, and gate of the second MOS tube, respectively. When port HO of gate driver U1 outputs a high level, the first MOS tube is turned on, and when it outputs a low level, the first MOS tube is turned off. When port LO outputs a high level, the second MOS tube is turned on, and when it outputs a low level, the second MOS tube is turned off. Gate driver U1 controls the two MOS tubes in the MOS tube half-bridge circuit to conduct alternately, providing variable AC power to the primary winding of the isolation transformer.

[0036] The first rectifier circuit includes a rectifier bridge and capacitor C8, and the second rectifier circuit includes a rectifier bridge and capacitor C12. The alternating current output from the first winding on the secondary side of the isolation transformer T1 is rectified by the rectifier bridge of the first rectifier circuit and then charges the capacitor C8, thereby providing a stable driving power supply; the alternating current output from the second winding on the secondary side of the isolation transformer T1 is rectified by the rectifier bridge of the second rectifier circuit and then charges the capacitor C12, thereby providing another stable driving power supply; thus, a unified driving power supply that can drive parallel IGBTs is provided.

[0037] As can be seen from the above, the embodiment of the utility model drives the MOS tube half-bridge circuit through the gate drive circuit to provide changing alternating current for the primary winding of the isolation transformer. After the alternating current is isolated and transformed by the isolation transformer, it is rectified by the first rectifier circuit to provide a stable driving power supply and rectified by the second rectifier circuit to provide another stable driving power supply. In this way, a unified driving power supply that can drive parallel IGBTs is provided.

[0038] Considering that the peak current generated when the isolation transformer T1 starts up may burn out the MOSFET in the MOSFET half-bridge circuit, in order to avoid the peak current generated when the isolation transformer T1 starts up burning out the MOSFET in the MOSFET half-bridge circuit, such as Figure 1 As shown, the isolated half-bridge IGBT drive power supply of the embodiment of the utility model also includes a current limiting resistor circuit, which is connected in series with the primary winding of the isolation transformer. The current limiting resistor circuit can limit the peak current generated when the isolation transformer T1 is started, thereby protecting the MOS tube. Figure 2 As shown, the current limiting resistor circuit may include a resistor R11, and the resistor R11 is connected in series with the primary winding of the isolation transformer. Of course, the current limiting resistor circuit may also include multiple resistors. In steady state, the excitation current of the isolation transformer T1 is small, and the voltage drop generated on the resistor R11 can be ignored.

[0039] Furthermore, in order to make the working timing of the driving power supply controllable and improve the stability of the power supply, such as Figure 1 As shown, the isolated half-bridge IGBT drive power supply of the embodiment of the utility model further includes a power supply circuit and a delayed power-on circuit; the power supply circuit is connected to the enable terminal of the gate drive circuit via the delayed power-on circuit, and the delayed power-on circuit is used to delay the power-on of the gate drive circuit. Figure 2 As shown, the power supply circuit is a 24V power supply, and the delayed power-on circuit includes an RC delay circuit, a first triode switch circuit and a second triode switch circuit; the power supply circuit is connected to the base of the triode in the first triode switch circuit via the RC delay circuit, and the first triode switch circuit outputs a low level when the triode in the first triode switch circuit is turned on, and the first triode switch circuit outputs a high level when the triode in the first triode switch circuit is turned off; the output end of the first triode switch circuit is connected to the base of the triode in the second triode switch circuit, and the enable end of the gate drive circuit is grounded via the triode in the second triode switch circuit.

[0040] Specifically, the RC delay circuit includes a resistor R7, a capacitor C11, a diode D6 and a voltage-stabilizing diode D7, the first transistor switch circuit includes a resistor R6 and a transistor T3, the second transistor switch circuit includes a transistor T2, the power supply circuit is connected to ground via the resistor R7 and the capacitor C11 in sequence, the diode D6 is connected in reverse parallel to the resistor R7, the common end of the resistor R7 and the capacitor C11 is connected to the base of the transistor T3, the voltage-stabilizing diode D7 is connected in reverse series between the common end of the resistor R7 and the capacitor C11 and the base of the transistor T3, the power supply circuit is also connected to ground via the resistor R6 and the transistor T3 in sequence, the collector of the transistor T3 is the output end of the first transistor switch circuit connected to the base of the transistor T2, and the enable end of the gate drive circuit is connected to ground via the transistor T2.

[0041] Resistor R7 and capacitor C11 form an RC charging circuit. When the 24V power supply starts to charge capacitor C11, the voltage-stabilizing diode D7 is cut off, the base of transistor T3 is at a low level, transistor T3 is turned off, and the 24V power supply provides a high level for the base of transistor T2 through resistors R6 and R9. Transistor T2 is turned on to pull the enabling terminal level of gate driver U1 down to ground, and gate driver U1 does not work; when the 24V power supply charges capacitor C11 to a certain voltage, the voltage-stabilizing diode D7 is turned on, the base of transistor T3 is at a high level, transistor T3 is turned on to pull the base level of transistor T2 down to ground, transistor T2 is turned off, the clock of gate driver U1 is unblocked, and the working sequence is established. Among them, if there is no voltage-stabilizing diode D7, the time required for transistor T3 to turn on is shorter. The voltage-stabilizing diode D7 is used to raise the conduction threshold of transistor T3, thereby increasing the enabling delay time of gate driver U1. When the power is off, the diode D6 is used to provide a quick release channel for the charge accumulated on the capacitor C11.

[0042] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0043] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An isolated half-bridge IGBT drive power supply, characterized in that: It includes a gate drive circuit, a MOS tube half-bridge circuit, an isolation transformer, a first rectifier circuit and a second rectifier circuit; The gate driving circuit is connected to the MOS tube half-bridge circuit, and the gate driving circuit is used to drive the MOS tube half-bridge circuit; The output end of the MOS tube half-bridge circuit is connected to the primary winding of the isolation transformer, and the MOS tube half-bridge circuit is used to supply power to the primary winding of the isolation transformer; The first winding of the secondary side of the isolation transformer is connected to the first rectifier circuit, and the second winding of the secondary side of the isolation transformer is connected to the second rectifier circuit.

2. The isolated half-bridge IGBT driving power supply according to claim 1, characterized in that: It also includes a current limiting resistor circuit, which is connected in series with the primary winding of the isolation transformer.

3. The isolated half-bridge IGBT driving power supply according to claim 2, characterized in that: The current limiting resistor circuit includes a resistor R11, and the resistor R11 is connected in series with the primary winding of the isolation transformer.

4. The isolated half-bridge IGBT driving power supply according to claim 1, characterized in that: It also includes a power supply circuit and a delayed power-on circuit; The power supply circuit is connected to the enable terminal of the gate driving circuit via the delayed power-on circuit, and the delayed power-on circuit is used to delay the power-on of the gate driving circuit.

5. The isolated half-bridge IGBT driving power supply according to claim 4, characterized in that: The delayed power-on circuit includes an RC delay circuit, a first transistor switch circuit and a second transistor switch circuit; The power supply circuit is connected to the base of the transistor in the first transistor switch circuit via the RC delay circuit, and the first transistor switch circuit outputs a low level when the transistor in the first transistor switch circuit is turned on, and the first transistor switch circuit outputs a high level when the transistor in the first transistor switch circuit is turned off; The output end of the first transistor switch circuit is connected to the base of the transistor in the second transistor switch circuit, and the enable end of the gate drive circuit is grounded via the transistor in the second transistor switch circuit.

6. The isolated half-bridge IGBT driving power supply according to claim 5, characterized in that: The RC delay circuit includes a resistor R7 and a capacitor C11; The power supply circuit is connected to ground via a resistor R7 and a capacitor C11 in sequence, and a common end of the resistor R7 and the capacitor C11 is connected to the base of the transistor in the first transistor switch circuit.

7. The isolated half-bridge IGBT driving power supply according to claim 6, characterized in that: The RC delay circuit further includes a diode D6, which is connected in reverse parallel to the resistor R7.

8. The isolated half-bridge IGBT driving power supply according to claim 6, characterized in that: The RC delay circuit further includes a voltage stabilizing diode D7, which is reversely connected in series between the common end of the resistor R7 and the capacitor C11 and the transistor base of the first transistor switch circuit.

9. The isolated half-bridge IGBT driving power supply according to claim 5, characterized in that: The first transistor switch circuit includes a resistor R6 and a transistor T3; The power supply circuit is connected to the base of transistor T3 via the RC delay circuit. The power supply circuit is also connected to ground via resistor R6 and transistor T3 in sequence. The collector of transistor T3 is the output end of the first transistor switch circuit.

10. The isolated half-bridge IGBT driving power supply according to claim 5, characterized in that: The second transistor switch circuit comprises a transistor T2; The output end of the first transistor switch circuit is connected to the base of the transistor T2, and the enable end of the gate drive circuit is grounded via the transistor T2.

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