Driving circuit

Abstract

The utility model discloses a drive circuit, which is characterized in that a U-phase motor drive circuit, a V-phase motor drive circuit and a W-phase motor drive circuit are respectively provided with a pre-drive chip connected with a main control chip MCU and an IGBT module; according to the utility model, through the arrangement of the pre-driving chip, a low-power signal output by the main control chip MCM is converted into a high-power output signal capable of effectively driving the IGBT module, and the high-power output signal is used for driving the motor to rotate, so that the problem of low driving voltage and current of the main control chip MCU is solved, the driving capability of the motor driving circuit is improved, and the motor driving circuit can drive the motor with relatively high power; and the accuracy of motor control and the operation efficiency of the motor are improved.

Description

Technical Field

[0001] This utility model relates to the field of driving circuit technology, specifically to a driving circuit. Background Technology

[0002] Three-phase brushless motors, as a key power system in modern electronic devices, are widely used in the water pump industry due to their high efficiency, low noise, and long lifespan. Compared with traditional brushed motors, three-phase brushless motors eliminate brushes, solving electrical and mechanical noise problems and greatly improving reliability. However, to achieve precise control and efficient operation, three-phase brushless motors exhibit high technical complexity in structural design, position detection, and driving methods. Currently, most brushless motor drives use MCU output PWM signals to directly control the IGBT module to turn off and drive the motor rotation. Although this method integrates control logic, signal processing, and driving functions onto a single chip, reducing the number of external components and lowering system complexity and cost, the output driving capability of the MCU is usually weak and cannot directly drive high-power water pump motors. Furthermore, it is prone to IGBT module bridge arm shoot-through, resulting in low system reliability. Therefore, a driving circuit is proposed. Utility Model Content

[0003] The main purpose of this utility model is to provide a solution that can effectively address the problems in the background art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a driving circuit, including three sets of motor driving circuits (UVW), a main control chip MCU1 connected to the three sets of motor driving circuits (UVW), and a motor. Each of the three sets of motor driving circuits (UVW) is provided with an IGBT module connected to the main control chip MCU and the motor. The three sets of motor driving circuits (UVW) control the U phase, V phase, and W phase of the motor respectively, and each forms a U-phase motor driving circuit, a V-phase motor driving circuit, and a W-phase motor driving circuit. The characteristic feature is that each of the U-phase motor driving circuit, V-phase motor driving circuit, and W-phase motor driving circuit is provided with a pre-driver chip connected to the main control chip MCU1 and the IGBT module.

[0005] Preferably, the pre-drive chip includes a pre-drive chip U11 disposed in the U-phase motor drive circuit, a pre-drive chip U12 disposed in the V-phase motor drive circuit, and a pre-drive chip U13 disposed in the W-phase motor drive circuit.

[0006] Preferably, the IGBT module includes Q01 and Q02 connected to the pre-drive chip U11 for controlling the U-phase current of the motor, Q03 and Q04 connected to the pre-drive chip U12 for controlling the V-phase current of the motor, and Q05 and Q06 connected to the pre-drive chip U13 for controlling the W-phase current of the motor.

[0007] Preferably, the U-phase motor drive circuit includes pin 2 of the pre-drive chip U11 connected to the AH signal output by the main control chip MCU, pin 3 of the pre-drive chip U11 connected to the AL signal output by the main control chip MCU, a 15V power supply connected to pin 1 of the pre-drive chip U11, ground connected to pin 4 of the pre-drive chip U11, resistor R02 connected to pin 5 of the pre-drive chip U11, the base of Q02 connected to resistor R02, resistor R53 and capacitor C32 connected to resistor R02, and resistor R52 and capacitor C32 also connected to the collector of Q02; and the pre-drive chip U11... Pin 7 of chip 1 is connected to resistor R01, which is connected to the base of Q01. The emitter of Q01 is connected to the positive power supply P. Pin 6 of pre-driver chip U11 is connected to the collector of Q01 and the emitter of Q02. Resistor R01 and pin 6 of pre-driver chip U11 are also connected to resistor R51 and capacitor C31. The collector of Q01 and the emitter of Q02 are connected. Pin 8 of pre-driver chip U11 is connected to diode D11 and capacitor C04. Diode D11 is connected to a 15V DC voltage. Capacitor C04 is also connected to pin 6 of pre-driver chip U11.

[0008] Preferably, the V-phase motor drive circuit includes pin 2 of the pre-drive chip U12 connected to the BH signal output by the main control chip MCU, pin 3 of the pre-drive chip U12 connected to the BL signal output by the main control chip MCU, a 15V power supply connected to pin 1 of the pre-drive chip U12, ground connected to pin 4 of the pre-drive chip U12, a resistor R04 connected to pin 5 of the pre-drive chip U12, the base of Q04 connected to resistor R04, and a resistor R54 and a capacitor C34 connected to resistor R04. Resistor R54 and capacitor C34 are also connected to the collector of Q04. Pin 7 of chip 12 is connected to resistor R03, which is connected to the base of Q03. The emitter of Q03 is connected to the positive power supply P. Pin 6 of pre-driver chip U12 is connected to the collector of Q03 and the emitter of Q04. Resistor R03 and pin 6 of pre-driver chip U12 are also connected to resistor R53 and capacitor C33. The collector of Q03 and the emitter of Q04 are connected. Pin 8 of pre-driver chip U12 is connected to diode D12 and capacitor C05. Diode D12 is connected to a 15V power supply. Capacitor C05 is also connected to pin 6 of pre-driver chip U12.

[0009] Preferably, the W-phase motor drive circuit includes pin 2 of the pre-drive chip U13 connected to the CH signal output by the main control chip MCU, pin 3 of the pre-drive chip U13 connected to the CL signal output by the main control chip MCU, a 15V power supply connected to pin 1 of the pre-drive chip U13, ground connected to pin 4 of the pre-drive chip U13, resistor R06 connected to pin 5 of the pre-drive chip U13, the base of Q06 connected to resistor R06, resistor R56 and capacitor C36 connected to resistor R06, wherein resistor R56 and capacitor C36 are also connected to the collector of Q06, resistors R31, R32, R33 and R34; resistor R31, Resistors R32, R33, and R34 are connected to ground; resistor R05 is connected to pin 7 of pre-driver chip U13; the base of Q05 is connected to resistor R05; the positive power supply P is connected to the emitter of Q05; the collector of Q05 and the emitter of Q06 are connected to pin 6 of pre-driver chip U13; resistor R05 and pin 6 of pre-driver chip U13 are also connected to resistor R55 and capacitor C35; the collector of Q05 and the emitter of Q06 are connected; diode D13 and capacitor C06 are connected to pin 8 of pre-driver chip U13; diode D13 is connected to a 15V power supply; capacitor C06 is also connected to pin 6 of pre-driver chip U13.

[0010] Preferably, the conduction sequence of the IGBT modules, from largest to smallest, is as follows: Q01 and Q04 are turned on, Q01 and Q06 are turned on, Q03 and Q06 are turned on, Q03 and Q02 are turned on, Q05 and Q02 are turned on, and Q05 and Q04 are turned on.

[0011] This invention offers the following advantages: By using a pre-driver chip, the low-power signal output from the main control chip (MCU) is converted into a high-power output signal capable of effectively driving the IGBT module and driving the motor rotation. This solves the problem of low drive voltage and current of the MCU, improving the driving capability of the motor drive circuit and enabling it to drive higher-power motors. This enhances the accuracy of motor control and improves motor operating efficiency. Furthermore, the pre-driver chip incorporates overcurrent protection, undervoltage protection, and built-in shoot-through prevention. When the IGBT module experiences overcurrent or short circuit, it quickly responds and cuts off the gate current, preventing device damage. It also prevents the system from activating external power transistors under low drive voltage, avoiding IGBT module mis-triggering or damage due to undervoltage. It effectively prevents IGBT module bridge arm shoot-through, improving system reliability. Simultaneously, the pre-driver chip features dead-time control, dynamically adjusting the dead time based on changes in the IGBT module's operating voltage, current, and temperature. Extending the dead time under high temperature, high current, and high voltage conditions reduces the risk of IGBT module bridge arm shoot-through, ensuring reliable operation of the IGBT module under high voltage and high current conditions. Attached Figure Description

[0012] Figure 1 This is the overall schematic diagram of this utility model;

[0013] Figure 2 This is a schematic diagram of the U-phase motor drive circuit of this utility model;

[0014] Figure 3 This is a schematic diagram of the V-phase motor drive circuit of this utility model;

[0015] Figure 4 This is a schematic diagram of the U-phase motor drive circuit of this utility model;

[0016] Figure 5 This is a schematic diagram of the IGBT conduction sequence of this utility model.

[0017] Diagram Explanation: 1. Main control chip MCU; 2. UVW three-group motor drive circuit; 3. Motor; 4. Pre-drive chip; 5. IGBT module. Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0019] like Figure 1-5As shown, a driving circuit includes three sets of motor drive circuits 2 (UVW), a main control chip MCU1 connected to the three sets of motor drive circuits 2, and a motor 3. Each of the three sets of motor drive circuits 2 (UVW) is equipped with an IGBT module 5 connected to the main control chip MCU1 and the motor 3. The three sets of motor drive circuits 2 (UVW) control the U-phase, V-phase, and W-phase of the motor respectively, and each forms a U-phase motor drive circuit, a V-phase motor drive circuit, and a W-phase motor drive circuit. The characteristic feature is that each of the U-phase motor drive circuit, V-phase motor drive circuit, and W-phase motor drive circuit is equipped with a pre-driver chip 4 connected to the main control chip MCU1 and the IGBT module 5; through the setting of the pre-driver chip 4, the output of the main control chip MCU1 is... The low-power signal is converted into a high-power output signal that can effectively drive the IGBT module 5 to drive the motor 3. This solves the problem of low drive voltage and current of the main control chip MCU1, improves the driving capability of the motor drive circuit, and enables it to drive the larger power motor 3, thus improving the accuracy of motor 3 control and the operating efficiency of motor 3. Furthermore, the pre-drive chip 4 has built-in overcurrent protection, undervoltage protection, and embedded shoot-through prevention functions. When the IGBT module 5 experiences overcurrent or short circuit, it can quickly respond and cut off the gate current to prevent device damage. It can also prevent the system from turning on the external power transistor under low drive voltage, avoiding IGBT module 5 false triggering or damage due to undervoltage. It can also effectively prevent IGBT module 5 bridge arm shoot-through, improving system reliability. Simultaneously, the pre-drive chip 4 has a dead-time control function, which can dynamically adjust the dead time according to changes in the operating voltage, current, and temperature of the IGBT module 5. Extending the dead time under high temperature, high current, and high voltage conditions reduces the risk of IGBT module 5 bridge arm shoot-through, ensuring reliable operation of the IGBT module 5 under high voltage and high current conditions.

[0020] In one embodiment, the pre-drive chip 4 includes pre-drive chips U11, U12, and U13 respectively disposed in the UVW three-phase motor drive circuit; the IGBT module 5 includes Q01 and Q02 connected to the pre-drive chip U11 for controlling the U-phase current of the motor 3, Q03 and Q04 connected to the pre-drive chip U12 for controlling the V-phase current of the motor 3, and Q05 and Q06 connected to the pre-drive chip U13 for controlling the W-phase current of the motor 3.

[0021] In one embodiment, the U-phase motor drive circuit includes pin 2 of a pre-drive chip U11 connected to the AH signal output by the main control chip MCU1, pin 3 of the pre-drive chip U11 connected to the AL signal output by the main control chip MCU1, a 15V power supply connected to pin 1 of the pre-drive chip U11, ground connected to pin 4 of the pre-drive chip U11, a resistor R02 connected to pin 5 of the pre-drive chip U11, the base of Q02 connected to resistor R02, and a resistor R53 and a capacitor C32 connected to resistor R02. Resistor R52 and capacitor C32 are also connected to the collector of Q02. Pin 7 of chip U11 is connected to resistor R01, which is connected to the base of Q01. The emitter of Q01 is connected to the positive power supply P. Pin 6 of pre-driver chip U11 is connected to the collector of Q01 and the emitter of Q02. Resistor R01 and pin 6 of pre-driver chip U11 are also connected to resistor R51 and capacitor C31. The collector of Q01 and the emitter of Q02 are connected. Pin 8 of pre-driver chip U11 is connected to diode D11 and capacitor C04. Diode D11 is connected to a 15V DC voltage. Capacitor C04 is also connected to pin 6 of pre-driver chip U11.

[0022] In one embodiment, the V-phase motor drive circuit includes pin 2 of a pre-drive chip U12 connected to the BH signal output by the main control chip MCU1, pin 3 of a pre-drive chip U12 connected to the BL signal output by the main control chip MCU1, a 15V power supply connected to pin 1 of the pre-drive chip U12, ground connected to pin 4 of the pre-drive chip U12, a resistor R04 connected to pin 5 of the pre-drive chip U12, the base of a Q04 connected to resistor R04, and a resistor R54 and a capacitor C34 connected to resistor R04. Resistor R54 and capacitor C34 are also connected to the collector of Q04. Pin 7 of chip U12 is connected to resistor R03, which is connected to the base of Q03. The emitter of Q03 is connected to the positive power supply P. Pin 6 of pre-driver chip U12 is connected to the collector of Q03 and the emitter of Q04. Resistor R03 and pin 6 of pre-driver chip U12 are also connected to resistor R53 and capacitor C33. The collector of Q03 and the emitter of Q04 are connected. Pin 8 of pre-driver chip U12 is connected to diode D12 and capacitor C05. Diode D12 is connected to a 15V power supply. Capacitor C05 is also connected to pin 6 of pre-driver chip U12.

[0023] In one embodiment, the W-phase motor drive circuit includes pin 2 of a pre-drive chip U13 connected to the CH signal output by the main control chip MCU1, pin 3 of a pre-drive chip U13 connected to the CL signal output by the main control chip MCU1, a 15V power supply connected to pin 1 of the pre-drive chip U13, ground connected to pin 4 of the pre-drive chip U13, a resistor R06 connected to pin 5 of the pre-drive chip U13, the base of Q06 connected to resistor R06, a resistor R56 and a capacitor C36 connected to resistor R06, wherein the resistor R56 and capacitor C36 are also connected to the collector of Q06, and resistors R31, R32, R33 and R34; the resistor R 31. Resistors R32, R33, and R34 are connected to ground; resistor R05 is connected to pin 7 of pre-driver chip U13; the base of Q05 is connected to resistor R05; the positive power supply P is connected to the emitter of Q05; the collector of Q05 and the emitter of Q06 are connected to pin 6 of pre-driver chip U13; resistor R05 and pin 6 of pre-driver chip U13 are also connected to resistor R55 and capacitor C35; the collector of Q05 and the emitter of Q06 are connected; diode D13 and capacitor C06 are connected to pin 8 of pre-driver chip U13; diode D13 is connected to a 15V power supply; capacitor C06 is also connected to pin 6 of pre-driver chip U13.

[0024] In one embodiment, the conduction sequence of the IGBT modules 5, from largest to smallest, is as follows: Q01 and Q04 are on, Q01 and Q06 are on, Q03 and Q06 are on, Q03 and Q02 are on, Q05 and Q02 are on, and Q05 and Q04 are on. When the conduction sequence of the IGBT modules 5 is from largest to smallest, the motor 3 rotates counterclockwise; when the conduction sequence of the IGBT modules 5 is from smallest to largest, the motor 3 rotates clockwise. The on / off combination and frequency of the IGBT modules 5 are controlled according to the sequence and frequency of the PWM signals output by the main control chip MCU, thereby changing the rotation direction and speed of the motor 3.

[0025] In use, the main control chip MCU1 outputs three sets of signals: AH, AL, BH, BL and CH, CL, which are respectively connected to the three sets of drive circuits 2 (UVW). The three sets of drive circuits 2 (UVW) then control the three phases of the U, V, and W motors respectively, inputting a 220V AC voltage to the product. After internal conversion, a 15V DC voltage is generated and connected to pin 1 of the pre-drive chip 4 to power its startup. The MCU generates a PWM control signal, which enters from pins 2 and 3 of the pre-drive chip U11, U12, or U13. This PWM signal passes through the pre-drive chip U1... 1. After amplification and processing by pre-drive chips U12 and U13, the signal is output from pins 5 and 7 of pre-drive chips U11, U12, and U13. At this time, pin 8 of pre-drive chips U11, U12, and U13 is connected to an external 15V power supply to stabilize the output signal of pre-drive chip 4. Then, the signal is connected to IGBT module 5 through RC filter circuits. The IGBT module 5 is turned on and off according to the changes in the high and low levels of the PWM signal, thereby changing the on / off combination and frequency of IGBT module 5, thus changing the direction and speed of motor 3.

[0026] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A driving circuit, comprising three motor driving circuits (2) of type UVW, a main control chip MCU (1) connected to the three motor driving circuits (2) of type UVW, and a motor (3), wherein each of the three motor driving circuits (2) of type UVW is provided with an IGBT module (5) connected to the main control chip MCU (1) and the motor (3), wherein the three motor driving circuits (2) of type UVW control the U phase, V phase, and W phase of the motor respectively, and respectively form a U phase motor driving circuit, a V phase motor driving circuit, and a W phase motor driving circuit, characterized in that: The U-phase motor drive circuit, V-phase motor drive circuit, and W-phase motor drive circuit are all equipped with a pre-drive chip (4) that is connected to the main control chip MCU (1) and IGBT module (5).

2. The driving circuit according to claim 1, characterized in that: The pre-drive chip (4) includes a pre-drive chip U11 set in the U-phase motor drive circuit, a pre-drive chip U12 set in the V-phase motor drive circuit, and a pre-drive chip U13 set in the W-phase motor drive circuit.

3. The driving circuit according to claim 1, characterized in that: The IGBT module (5) includes Q01 and Q02 connected to the pre-drive chip U11 for controlling the U-phase current of the motor (3), Q03 and Q04 connected to the pre-drive chip U12 for controlling the V-phase current of the motor (3), and Q05 and Q06 connected to the pre-drive chip U13 for controlling the W-phase current of the motor (3).

4. The driving circuit according to claim 1, characterized in that: The U-phase motor drive circuit includes pin 2 of the pre-drive chip U11 connected to the AH signal output by the main control chip MCU (1), pin 3 of the pre-drive chip U11 connected to the AL signal output by the main control chip MCU (1), a 15V power supply connected to pin 1 of the pre-drive chip U11, ground connected to pin 4 of the pre-drive chip U11, a resistor R02 connected to pin 5 of the pre-drive chip U11, the base of Q02 connected to resistor R02, a resistor R53 and a capacitor C32 connected to resistor R02, and the resistor R52 and capacitor C32 are also connected to the collector of Q02; the pre-drive chip U11... Pin 7 of chip 11 is connected to resistor R01, which is connected to the base of Q01. The emitter of Q01 is connected to the positive power supply P. Pin 6 of pre-driver chip U11 is connected to the collector of Q01 and the emitter of Q02. Resistor R01 and pin 6 of pre-driver chip U11 are also connected to resistor R51 and capacitor C31. The collector of Q01 and the emitter of Q02 are connected. Pin 8 of pre-driver chip U11 is connected to diode D11 and capacitor C04. Diode D11 is connected to a 15V DC voltage. Capacitor C04 is also connected to pin 6 of pre-driver chip U11.

5. A driving circuit according to claim 1, characterized in that: The V-phase motor drive circuit includes pin 2 of the pre-drive chip U12 connected to the BH signal output by the main control chip MCU (1), pin 3 of the pre-drive chip U12 connected to the BL signal output by the main control chip MCU (1), a 15V power supply connected to pin 1 of the pre-drive chip U12, ground connected to pin 4 of the pre-drive chip U12, a resistor R04 connected to pin 5 of the pre-drive chip U12, the base of Q04 connected to resistor R04, a resistor R54 and a capacitor C34 connected to resistor R04, and the resistor R54 and capacitor C34 are also connected to the collector of Q04; and the pre-drive chip... Pin 7 of U12 is connected to resistor R03, which is connected to the base of Q03. The emitter of Q03 is connected to the positive power supply P. Pin 6 of the pre-driver chip U12 is connected to the collector of Q03 and the emitter of Q04. Resistor R03 and pin 6 of the pre-driver chip U12 are also connected to resistor R53 and capacitor C33. The collector of Q03 and the emitter of Q04 are connected. Pin 8 of the pre-driver chip U12 is connected to diode D12 and capacitor C05. Diode D12 is connected to a 15V power supply. Capacitor C05 is also connected to pin 6 of the pre-driver chip U12.

6. A driving circuit according to claim 1, characterized in that: The W-phase motor drive circuit includes pin 2 of the pre-drive chip U13 connected to the CH signal output of the main control chip MCU (1), pin 3 of the pre-drive chip U13 connected to the CL signal output of the main control chip MCU (1), a 15V power supply connected to pin 1 of the pre-drive chip U13, ground connected to pin 4 of the pre-drive chip U13, resistor R06 connected to pin 5 of the pre-drive chip U13, the base of Q06 connected to resistor R06, resistor R56 and capacitor C36 connected to resistor R06, resistor R56 and capacitor C36 also connected to the collector of Q06, resistor R31, resistor R32, resistor R33 and resistor R34; resistor R31 Resistors R32, R33, and R34 are connected to ground; resistor R05 is connected to pin 7 of pre-driver chip U13; the base of Q05 is connected to resistor R05; the positive power supply P is connected to the emitter of Q05; the collector of Q05 and the emitter of Q06 are connected to pin 6 of pre-driver chip U13; resistor R05 and pin 6 of pre-driver chip U13 are also connected to resistor R55 and capacitor C35; the collector of Q05 and the emitter of Q06 are connected; diode D13 and capacitor C06 are connected to pin 8 of pre-driver chip U13; diode D13 is connected to a 15V power supply; capacitor C06 is also connected to pin 6 of pre-driver chip U13.

7. A driving circuit according to any one of claims 2 to 4, characterized in that: The IGBT module (5) is turned on in the following order from largest to smallest: Q01 and Q04 are turned on, Q01 and Q06 are turned on, Q03 and Q06 are turned on, Q03 and Q02 are turned on, Q05 and Q02 are turned on, and Q05 and Q04 are turned on.

Images