IGBT (Insulated Gate Bipolar Translator) driving circuit for new energy automobile
By integrating an open-circuit protection unit into the IGBT drive circuit, the problem of the limited application scenarios of existing IGBT drive circuits in new energy vehicles is solved, and open-circuit protection for IGBTs is achieved, enhancing the safety and reliability of the circuit.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN SILICON MOUNTAIN TECH CO LTD
- Filing Date
- 2025-05-16
- Publication Date
- 2026-05-01
AI Technical Summary
Existing IGBT driver circuits are mainly used for overcurrent protection in new energy vehicles, with limited application scenarios and a lack of open-circuit protection.
An IGBT drive circuit with integrated open-circuit protection function was designed. The open-circuit protection of the IGBT is achieved by using a protection unit composed of resistors, capacitors, electrodes and diodes, combined with an IGBT drive optocoupler and an overcurrent protection unit.
In the DC high-voltage power circuit, open-circuit protection of IGBTs is realized, which enhances the safety and reliability of the circuit and avoids damage to IGBTs caused by open-circuit faults.
Smart Images
Figure CN224191919U_ABST
Abstract
Description
An IGBT drive circuit for new energy vehicles Technical Field
[0001] This utility model relates to the field of new energy vehicle technology, specifically to an IGBT drive circuit for new energy vehicles. Background Technology
[0002] With the development of the semiconductor industry, the application of semiconductor devices has become increasingly diverse, meeting a wide range of application scenarios. IGBTs, as the most commonly used semiconductor devices in new energy vehicles, are typically used in inverter circuits within new energy vehicle components to perform power conversion between DC high-voltage and AC high-voltage electricity.
[0003] Currently, most IGBT drive circuits in new energy vehicle components on the market implement overcurrent protection through the following methods: First, the IGBT output current is sampled by an IGBT output current sampling resistor to obtain a current sampling signal. This current sampling signal is transmitted not only to the optocoupler, operational amplifier, and DSP current sampling signal processing loop, but also simultaneously to the corresponding IGBT drive optocoupler. The drive optocoupler compares this current sampling signal. If the amplitude of the current sampling signal exceeds the preset output current sampling signal threshold in the drive optocoupler, the drive optocoupler immediately shuts off the drive signal, thus achieving the IGBT overcurrent protection function. In this application scenario, most IGBT drive circuits only provide overcurrent protection for the IGBT to avoid damage from overcurrent, resulting in a limited application scenario and a lack of open-circuit protection. Summary of the Invention
[0004] The purpose of this invention is to provide an IGBT drive circuit for new energy vehicles.
[0005] To achieve the above objectives, this utility model provides the following technical solution: an IGBT drive circuit for new energy vehicles, comprising:
[0006] The IGBT driving unit is used to acquire IGBT driving signals and output them to drive the IGBT to conduct, and to acquire current sampling signals, compare them, and control the output of IGBT driving signals. The IGBT driving unit is connected to the IGBT.
[0007] The overcurrent protection unit is used to convert the current output by the IGBT into a current sampling signal and then upload it to the IGBT driver unit; and
[0008] The open-circuit protection unit is used to send an IGBT open-circuit fault signal after acquiring the IGBT drive signal.
[0009] The open-circuit protection unit includes resistors R11, R21, R70, R77, R82, capacitors C1 and C48, transistor Q1, Zener diode D21, and anti-reverse diode D14. One end of resistor R11 is connected to the collector of transistor Q1. The base of transistor Q1 is connected to one end of resistor R70 through capacitor C1 and one end of resistor R77. The emitter of transistor Q1 is connected to the other end of capacitor C1 and resistor R77, and capacitor C1 and resistor R77 are connected in parallel. One end of capacitor C48 is connected to the IGBT driver unit, and the other end of capacitor C48 is connected to the positive terminal of anti-reverse diode D14 through resistor R21. The negative terminal of anti-reverse diode D14 is connected to the IGBT. The other end of resistor R70 is connected between resistor R21 and capacitor C48 through Zener diode D21. One end of resistor R82 is connected between R21 and anti-reverse diode D14, and the other end of resistor R82 is connected between the IGBT driver unit and the IGBT.
[0010] Furthermore, the IGBT driving unit includes an IGBT driving optocoupler U6, a resistor R61, and a resistor R53. One end of the resistor R61 is connected to the IGBT driving optocoupler U6, and the other end of the resistor R61 is connected to the DRV_IGBT network to obtain the IGBT driving signal. One end of the resistor R53 is connected between the resistor R82 and the IGBT driving unit, and the other end of the resistor R53 is connected to the IGBT.
[0011] Furthermore, it also includes an optocoupler driving unit that drives the IGBT drive optocoupler U6 to conduct after obtaining the IGBT drive optocoupler enable signal. The optocoupler driving unit includes a reverse protection diode Q6, resistors R66 and R3. One end of the reverse protection diode Q6 is connected to the IGBT drive optocoupler U6 through resistor R66, and the other end of the reverse protection diode Q6 is connected to the FLT_IGBT network to obtain the IGBT drive optocoupler enable signal. One end of the resistor R3 is connected between resistor R66 and IGBT drive optocoupler U6.
[0012] Furthermore, the overcurrent protection unit includes a resistor R49, one end of which is connected to the IGBT drive optocoupler U6, and the other end of which is connected to the IGBT.
[0013] Furthermore, it also includes a power supply unit for powering the IGBT drive optocoupler U6. The power supply unit includes resistors R45, R69, R2, capacitor C51, and transient suppression diode D9. One end of resistor R45 is connected to the power supply, and the other end is connected to the IGBT drive optocoupler U6. Resistor R69 and capacitor C51 are connected in parallel and then connected to the IGBT drive optocoupler U6. Resistor R69 and capacitor C51 are used for RC filtering. Resistor R2 and transient suppression diode D9 are connected in parallel and then connected between resistor R53 and the IGBT. Resistor R2 and transient suppression diode D9 are used to absorb transient spike noise on the IGBT drive signal.
[0014] As can be seen from the above technical solution, this utility model has the following beneficial effects:
[0015] Unlike existing IGBT driver circuits on the market, the IGBT driven by this IGBT driver circuit is not used for AC / DC high-voltage power conversion, but is used as a switch in the DC high-voltage power circuit. Therefore, unlike existing IGBT driver circuits, in this application scenario, in addition to the two basic functions of IGBT driving and overcurrent protection, this IGBT driver circuit also integrates open-circuit protection to detect whether the current DC high-voltage circuit path is normal. Attached Figure Description
[0016] Figure 1 is the overall circuit diagram of this utility model. Detailed Implementation
[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0018] As shown in Figure 1, this utility model provides an IGBT drive circuit for new energy vehicles, including an optocoupler drive unit, a power supply unit, an IGBT drive unit, an overcurrent protection unit, and an open circuit protection unit. The optocoupler drive unit includes a reverse protection diode Q6, resistors R66 and R3. One end of the reverse protection diode Q6 is connected to the IGBT drive optocoupler U6 through resistor R66, and the other end of the reverse protection diode Q6 is connected to the FLT_IGBT network to obtain the IGBT drive optocoupler enable signal. One end of the resistor R3 is connected between resistor R66 and IGBT drive optocoupler U6.
[0019] The IGBT driver unit includes an IGBT driver optocoupler U6, a resistor R61, and a resistor R53. One end of the resistor R61 is connected to the IGBT driver optocoupler U6, and the other end of the resistor R61 is connected to the DRV_IGBT network to obtain the IGBT drive signal. One end of the resistor R53 is connected between the resistor R82 and the IGBT driver optocoupler U6, and the other end of the resistor R53 is connected to the IGBT through a parallel resistor R2 and a transient suppression diode D9.
[0020] The IGBT drive optocoupler enable signal is connected to the optocoupler drive unit via the FLT_IGBT network. After passing through the anti-reverse diode Q6 and the current-limiting resistor R66, it is transmitted to pin 5 (EN / nFLT) of the IGBT drive optocoupler U6, thus putting the IGBT drive optocoupler U6 into operation. Furthermore, to ensure stable operation of the drive optocoupler U6, the IGBT drive optocoupler enable signal FLT_IGBT is pulled up through the power supply VDD and the pull-up resistor R3 to ensure its reliability. In the above-mentioned operating state of the IGBT drive optocoupler U6, if input pin 6 (IN) of the IGBT drive optocoupler U6 receives the IGBT drive signal input from the DRV_IGBT network and current-limited by the current-limiting resistor R61, then its output pin 3 (OUT) will also output the corresponding IGBT drive signal Vout, ultimately driving the IGBT to conduct through the drive resistor R53.
[0021] The power supply unit includes resistors R45, R69, and R2, capacitor C51, and transient suppression diode D9. One end of resistor R45 is connected to the power supply, and the other end is connected to IGBT driver optocoupler U6. Resistor R69 and capacitor C51 are connected in parallel and then connected to IGBT driver optocoupler U6, where they perform RC filtering. Resistor R2 and transient suppression diode D9 are connected in parallel and then connected between resistor R53 and the IGBT. Resistor R2 and transient suppression diode D9 are used to absorb transient spike noise on the IGBT drive signal. The power supply unit also includes a Zener diode D5 and capacitor C39. One end of the Zener diode D5 and capacitor C39 are connected in parallel and then connected between resistor R45 and IGBT driver optocoupler U6, while the other end is connected between capacitor C48 and IGBT driver optocoupler U6. In this circuit, the power supply for the IGBT driver optocoupler U6 is connected to the VCC network and then supplied to the IGBT driver optocoupler U6 after passing through the current limiting resistor R45. Resistor R69 and capacitor C51 are used to perform RC filtering on the IGBT drive signal DRV_IGBT. Resistor R2 and transient suppression diode D9 are used to absorb transient spike noise on the IGBT drive signal to protect the IGBT driver optocoupler U6 from breakdown and damage.
[0022] The overcurrent protection unit includes a resistor R49. One end of resistor R49 is connected to the IGBT driver optocoupler U6, and the other end is connected to the IGBT. Resistor R49 serves as the IGBT output current sampling resistor. By adding the IGBT output current sampling resistor R49 and combining it with the overcurrent comparison and judgment circuit integrated within the IGBT driver optocoupler U6, the overcurrent protection function is achieved. When the IGBT is in the on state, its output current IOUT flows through the IGBT output current sampling resistor R49 to form a corresponding current sampling signal VIGBT. This current sampling signal VIGBT is transmitted to pins 1 and 2 (i.e., COM and OCP) of the IGBT driver optocoupler U6. Then, it is compared with a preset output current sampling signal threshold by the comparison and judgment circuit inside the IGBT driver optocoupler U6. If the current current sampling signal VIGBT is higher than the preset threshold, the IGBT driver optocoupler U6 will immediately shut down the IGBT drive signal output and simultaneously set the "EN / nFLT" signal at pin 5 low, thereby achieving the purpose of IGBT overcurrent protection and simultaneously reporting an IGBT fault.
[0023] The open-circuit protection unit includes resistors R11, R21, R70, R77, R82, capacitors C1 and C48, transistor Q1, Zener diode D21, and reverse protection diode D14. One end of resistor R11 is connected to the collector of transistor Q1. The base of transistor Q1 is connected to one end of resistor R70 through capacitor C1 and one end of resistor R77. The emitter of transistor Q1 is connected to the other end of capacitor C1 and resistor R77, and capacitor C1 and resistor R77 are connected in parallel. One end of capacitor C48 is connected to the IGBT driver unit, and the other end of capacitor C48 is connected to the positive terminal of reverse protection diode D14 through resistor R21. The negative terminal of reverse protection diode D14 is connected to the IGBT. The other end of resistor R70 is connected between resistor R21 and capacitor C48 through Zener diode D21. One end of resistor R82 is connected between R21 and reverse protection diode D14, and the other end of resistor R82 is connected between the IGBT driver unit and the IGBT.
[0024] Under normal operating conditions, the DC high-voltage power input is connected to this circuit via J2. After passing through the conducting IGBT and the IGBT output current sampling resistor R49, the current flows back to the DC high-voltage power ground (BAT-), forming a complete DC high-voltage power loop. However, if the IGBT in the circuit is in an open-circuit state, the DC high-voltage current connected via J2 cannot flow back to the power ground. That is, J2 cannot be approximately equivalent to the power ground BAT-, and J2 is in a high-level state. Therefore, in this state, the IGBT drive signal Vout output from pin 3 of the IGBT drive optocoupler U6, after passing through resistor R82, cannot be output to the power ground BAT- via the anti-reverse diode D14, the IGBT, and the IGBT output current sampling resistor R49. Instead, it charges capacitor C48 through resistor R21. Therefore, after a charging time of τ [i.e., (R82+R21)*C48], capacitor C48 can be charged to the threshold voltage Vopen (i.e., 0.632*Vout). Considering that the threshold voltage Vopen reached by the capacitor is different under different drive voltages Vout, this threshold voltage Vopen can only be used to drive transistor Q1 to conduct after being regulated by Zener diode D21. By adjusting the use of Zener diodes with different regulated values, it can be ensured that transistor Q1 can be driven to conduct normally through resistors R70, R77, and capacitor C1 under different drive voltage Vout application scenarios. If transistor Q1 conducts, the IGBT fault signal "FLT_IGBT" (which is also multiplexed as the IGBT drive optocoupler enable signal and IGBT overcurrent fault signal) pulled up by VDD through resistor R11 can be pulled low, and IGBT drive optocoupler U6 can enter the drive shutdown state, thereby achieving the purpose of open circuit protection and simultaneously reporting IGBT open circuit fault.
[0025] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. An IGBT drive circuit for new energy vehicles, characterized in that, include: The IGBT driving unit is used to acquire IGBT driving signals and output them to drive the IGBT to conduct, and to acquire current sampling signals, compare them, and control the output of the IGBT driving signals. The IGBT driving unit is connected to the IGBT. The overcurrent protection unit is used to convert the current output by the IGBT into a current sampling signal and upload it to the IGBT driving unit. And an open-circuit protection unit, used to send an IGBT open-circuit fault signal after acquiring the IGBT drive signal; wherein, the open-circuit protection unit includes resistors R11, R21, R70, R77, R82, capacitors C1, C48, transistor Q1, Zener diode D21, and anti-reverse diode D14. One end of resistor R11 is connected to the collector of transistor Q1, the base of transistor Q1 is connected to one end of resistor R70 through capacitor C1 and one end of resistor R77, and the emitter of transistor Q1 is connected to capacitor C1 and resistor R77. At the other end, capacitor C1 and resistor R77 are connected in parallel. One end of capacitor C48 is connected to the IGBT driving unit, and the other end of capacitor C48 is connected to the positive terminal of anti-reverse diode D14 through resistor R21. The negative terminal of anti-reverse diode D14 is connected to the IGBT. The other end of resistor R70 is connected between resistor R21 and capacitor C48 through Zener diode D21. One end of resistor R82 is connected between R21 and anti-reverse diode D14, and the other end of resistor R82 is connected between the IGBT driving unit and the IGBT.
2. The IGBT drive circuit for new energy vehicles according to claim 1, characterized in that: The IGBT driving unit includes an IGBT driving optocoupler U6, a resistor R61, and a resistor R53. One end of the resistor R61 is connected to the IGBT driving optocoupler U6, and the other end of the resistor R61 is connected to the DRV_IGBT network to obtain the IGBT driving signal. One end of the resistor R53 is connected between the resistor R82 and the IGBT driving unit, and the other end of the resistor R53 is connected to the IGBT.
3. The IGBT drive circuit for new energy vehicles according to claim 2, characterized in that: It also includes an optocoupler driving unit that drives the IGBT drive optocoupler U6 to conduct after obtaining the IGBT drive optocoupler enable signal. The optocoupler driving unit includes a reverse protection diode Q6, resistors R66 and R3. One end of the reverse protection diode Q6 is connected to the IGBT drive optocoupler U6 through resistor R66, and the other end of the reverse protection diode Q6 is connected to the FLT_IGBT network to obtain the IGBT drive optocoupler enable signal. One end of the resistor R3 is connected between resistor R66 and IGBT drive optocoupler U6.
4. The IGBT drive circuit for new energy vehicles according to claim 2, characterized in that: The overcurrent protection unit includes a resistor R49, one end of which is connected to the IGBT drive optocoupler U6, and the other end of which is connected to the IGBT.
5. The IGBT drive circuit for new energy vehicles according to claim 2, characterized in that: It also includes a power supply unit for powering the IGBT drive optocoupler U6. The power supply unit includes resistors R45, R69, R2, capacitor C51, and transient suppression diode D9. One end of resistor R45 is connected to the power supply, and the other end is connected to the IGBT drive optocoupler U6. Resistor R69 and capacitor C51 are connected in parallel and then connected to the IGBT drive optocoupler U6. Resistor R69 and capacitor C51 are used for RC filtering. Resistor R2 and transient suppression diode D9 are connected in parallel and then connected between resistor R53 and the IGBT. Resistor R2 and transient suppression diode D9 are used to absorb transient spike noise on the IGBT drive signal.