A SiC three-phase bridge drive circuit module and circuit based on SIP technology

Abstract

A SiC three-phase bridge drive circuit module and circuit based on SIP technology relate to the field of integrated circuit technology. The SiC three-phase bridge drive circuit module includes a SiC three-phase bridge drive circuit and a metal heat sink, a metal cover, an insulating housing, a lower substrate, and an upper substrate. The SiC three-phase bridge drive circuit includes a power conversion circuit, a four-channel isolated power supply, a six-way SiC MOSFET drive circuit, and a SiC MOSFET three-phase full-bridge power module. The SiC MOSFET three-phase full-bridge power module is arranged on the lower substrate, and the power conversion circuit, four-channel isolated power supply, and six-way SiC MOSFET drive circuit are arranged on the upper substrate. The present invention adopts systematic packaging (SIP) technology to package active chips and passive components into the same module. The latter stage can directly drive a high-voltage three-phase brushless DC motor, achieving miniaturization, modularization, and lightweighting of SiC MOSFET drive.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuits, and in particular to a SiC three-phase bridge drive circuit module and circuit based on SIP technology. Background Art

[0002] Silicon carbide (SiC) is a semiconductor compound composed of silicon (Si) and carbon (C), belonging to the wide bandgap (WBG) family of materials. Its strong physical bond gives the semiconductor high mechanical, chemical, and thermal stability. MOSFETs made from SiC offer the following advantages: reduced power loss, high-temperature operation, high-speed switching, excellent heat dissipation, and shorter reverse recovery time. Because SiC MOSFETs can operate at higher frequencies and temperatures without compromising reliability, they are widely used in applications including converters, inverters, power supplies, battery chargers, and motor control systems.

[0003] While SiC MOSFETs offer higher operational capabilities, their driver circuits differ from and are more complex than those used in traditional Si-based MOSFETs. SiC MOSFETs are used in high-voltage, high-power power supply applications. To prevent excessive crosstalk from the power stage to the preceding stage, an isolated power supply is required. To ensure reliable shutdown of the SiC MOSFET, a negative voltage driver is required. Furthermore, SiC MOSFETs experience significant voltage and current overshoots in high-voltage, high-power applications, necessitating the use of various protection circuits.

[0004] Patent CN202223280136, "A Low-Inductance SiC Power Module Packaging Structure," proposes a SiC chip packaging method and structure with low parasitic inductance to improve the electrothermal performance of SiC power modules. However, this structure requires an external drive circuit to drive the SiC chip.

[0005] Patent CN202220961577, "A SiC MOSFET Drive and Protection Self-Reset Circuit for V2G On-Board Converters," proposes a SiC drive circuit with integrated protection circuitry, capable of driving half-bridge SiC modules. However, the patent is not comprehensive in its scope for SiC drive applications. For one thing, it only drives half-bridge SiC modules, while three-phase full-bridge SiC modules are more common in actual projects. Furthermore, the patent only integrates the driver chip and peripheral circuitry, without an isolated power supply, requiring an external isolated power supply to drive the SiC module.

[0006] Currently, the industry typically develops SiC MOSFET drivers by separately developing the isolated power supply, drive circuit, and power module. This results in overly complex systems and occupies too much space. Therefore, SiC MOSFET drivers inevitably require system miniaturization, modularization, and lightweighting. Summary of the Invention

[0007] The purpose of the present invention is to provide a SiC three-phase bridge drive circuit module and circuit based on SIP technology, which integrates the isolated power supply, drive circuit, and power module into the same circuit module, thereby reducing the space occupied by the SiC MOSFET drive. The back stage can directly drive a high-voltage three-phase brushless DC motor. At the same time, the system packaging SIP technology is used to package the active chip (bare core) and passive components into the same module, thereby realizing the miniaturization, modularization, and lightweight of the SiC MOSFET drive.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a SiC three-phase bridge drive circuit, including a power conversion circuit, a four-channel isolated power supply, a six-way SiC MOSFET drive circuit, and a SiC MOSFET three-phase full-bridge power module, wherein:

[0009] The input terminal of the power conversion circuit is connected to the control power supply. The +12V power output provides power input for the PWM controller in the four-channel isolated power supply, and the +5V power output provides power input for the six-channel SiC MOSFET drive circuit. The power conversion circuit adopts the existing power supply design scheme in the industry.

[0010] The four-channel isolated power supply includes a PWM controller and a four-channel isolation transformer, which is used to convert the control power supply into four isolated power supplies: a U-phase high-side isolated power supply, a V-phase high-side isolated power supply, a W-phase high-side isolated power supply, and a low-side isolated power supply. Each isolated power supply includes +18V, -5V, and GND zero potential, providing isolated power and GND zero potential for six SiC MOSFET drive circuits; the four-channel isolated power supply adopts a flyback isolated power supply solution.

[0011] The six-way SiC MOSFET drive circuit is used to convert the six PWM control signals output by the motor control unit, namely the U-phase high-side control signal, U-phase low-side control signal, V-phase high-side control signal, V-phase low-side control signal, W-phase high-side control signal, and W-phase low-side control signal, into six isolated drive signals, namely the U-phase high-side isolated drive signal, the U-phase low-side isolated drive signal, the V-phase high-side isolated drive signal, the V-phase low-side isolated drive signal, the W-phase high-side isolated drive signal, and the W-phase low-side isolated drive signal; wherein the U-phase high-side, V-phase high-side, and W-phase high-side drive circuits use the U-phase high-side isolated power supply, the V-phase high-side isolated power supply, and the W-phase high-side isolated power supply, respectively, and the U-phase low-side, V-phase low-side, and W-phase low-side drive circuits all use the low-side isolated power supply; the six-way SiC MOSFET drive circuit adopts the existing technology drive solution in the industry.

[0012] The SiC MOSFET three-phase full-bridge power module is used to turn on the six SiC MOSFETs in a timed sequence under the control of the six isolated drive signals, and output U-phase, V-phase, and W-phase drive currents to drive a three-phase brushless DC motor; the SiC MOSFET three-phase full-bridge power module also adopts the existing full-bridge power module solution in the industry.

[0013] The SiC MOSFET three-phase full-bridge power module is further provided with a thermistor, and the positive and negative ends of the thermistor are used to be connected to the motor control unit.

[0014] Furthermore, the voltage input range of the control power supply is +12V to +75V, and the rated input voltage is +28V.

[0015] Furthermore, the specific structure of the four-channel isolated power supply is:

[0016] A power supply input pin of the PWM controller is connected to a +12V power supply output by the power conversion circuit via a sixteenth resistor; an output pin of the PWM controller is connected to a gate of a second MOS transistor via a twenty-first resistor; a drain of the second MOS transistor and a control power supply are respectively connected to two ends of a primary coil of an isolation transformer; a source of the second MOS transistor is connected to a ground potential via a thirty-first resistor and is connected to a current detection input pin of the PWM controller via a twenty-fourth resistor;

[0017] The isolation transformer has four secondary coils, and the primary coil and the secondary coil have opposite ends.

[0018] The first secondary coil of the isolation transformer is connected in series with a first diode, a twelfth capacitor is connected in parallel on the first parallel branch of the first diode, a ninth resistor is connected in parallel on the second parallel branch, an eighth capacitor and a fifteenth capacitor are connected in series on the third parallel branch, a seventh resistor and a third voltage-stabilizing diode are connected in series on the fourth parallel branch, a connection point between the eighth capacitor and the fifteenth capacitor is connected to a connection point between the seventh resistor and the negative electrode of the third voltage-stabilizing diode, serving as the zero potential of the U-phase high-side isolated power supply, the negative electrode of the first diode serves as the +18V output end of the U-phase high-side isolated power supply, and the positive electrode of the third voltage-stabilizing diode serves as the -5V output end of the U-phase high-side isolated power supply;

[0019] The second secondary coil of the isolation transformer is connected in series with a sixth diode, the first parallel branch of the sixth diode is connected in parallel with a seventeenth capacitor, the second parallel branch is connected in parallel with a fourteenth resistor, the third parallel branch is connected with a sixteenth capacitor and a nineteenth capacitor connected in series, the fourth parallel branch is connected with a thirteenth resistor and a tenth voltage-stabilizing diode connected in series, the connection point between the sixteenth capacitor and the nineteenth capacitor is connected to the connection point between the thirteenth resistor and the negative electrode of the tenth voltage-stabilizing diode, serving as the zero potential of the V-phase high-side isolated power supply, the negative electrode of the sixth diode serves as the +18V output end of the V-phase high-side isolated power supply, and the positive electrode of the tenth voltage-stabilizing diode serves as the -5V output end of the V-phase high-side isolated power supply;

[0020] The third secondary coil of the isolation transformer is connected in series with an eleventh diode, the first parallel branch of the eleventh diode is connected in parallel with a twenty-ninth capacitor, the second parallel branch thereof is connected in parallel with a thirty-third resistor, the third parallel branch thereof is connected with a twenty-fifth capacitor and a thirty-fifth capacitor connected in series, the fourth parallel branch thereof is connected with a twenty-ninth resistor and a thirteenth voltage-stabilizing diode connected in series, the connection point between the twenty-fifth capacitor and the thirty-fifth capacitor is connected to the connection point between the twenty-ninth resistor and the cathode of the thirteenth voltage-stabilizing diode, serving as the zero potential of the W-phase high-side isolated power supply, the cathode of the eleventh diode serves as the +18V output end of the W-phase high-side isolated power supply, and the anode of the thirteenth voltage-stabilizing diode serves as the -5V output end of the W-phase high-side isolated power supply;

[0021] The fourth secondary coil of the isolation transformer is connected in series with a fourteenth diode, the first parallel branch of the fourteenth diode is connected in parallel with a thirty-ninth capacitor, the second parallel branch thereof is connected in parallel with a forty-eighth resistor, the third parallel branch thereof is connected with the thirty-eighth capacitor and the forty-first capacitor connected in series, the fourth parallel branch thereof is connected with the forty-sixth resistor and the sixteenth voltage-stabilizing diode connected in series, the connection point between the thirty-eighth capacitor and the forty-first capacitor is connected to the connection point between the forty-sixth resistor and the cathode of the sixteenth voltage-stabilizing diode, serving as the zero potential of the low-side isolated power supply, the cathode of the fourteenth diode serves as the +18V output end of the low-side isolated power supply, and the anode of the sixteenth voltage-stabilizing diode serves as the -5V output end of the low-side isolated power supply;

[0022] Two ends of a sixty-seventh sampling resistor and a seventy-seventh sampling resistor connected in series are respectively connected to the +18V output end of the U-phase high-side isolated power supply and the -5V output end of the U-phase high-side isolated power supply, and the connection point between the sixty-seventh sampling resistor and the seventy-seventh sampling resistor is connected to the REF reference electrode of the voltage reference source, the anode of the voltage reference source is connected to the -5V output end of the U-phase high-side isolated power supply, and the cathode is connected to the +18V output end of the U-phase high-side isolated power supply through the sixty-third bias resistor;

[0023] The positive electrode of the optocoupler diode is connected to the +18V output terminal of the U-phase high-side isolated power supply through the fifty-seventh resistor, and the negative electrode is connected to the cathode of the voltage reference source; the emitter of the optocoupler transistor is connected to the ground potential through the sixty-ninth resistor, the collector is connected to the inverting input pin of the PWM controller, and the collector is also connected to the internal reference voltage output pin of the PWM controller through the thirty-seventh resistor.

[0024] Furthermore, the SiC MOSFET three-phase full-bridge power module also has a discharge circuit, and the specific structure of the discharge circuit is:

[0025] The gate of the thirty-sixth SiC MOSFET is connected to the discharge control signal output by the motor control unit, the drain is connected to the power supply via the one hundred and third SiC Schottky diode, and the source is connected to the power supply ground;

[0026] A one-hundred-and-seventy-fourth capacitor and a one-hundred-and-second resistor are connected in series between the drain and source of the thirty-sixth SiC MOSFET tube. The connection point between the one-hundred-and-seventy-fourth capacitor and the one-hundred-and-second resistor is connected to the anode of the one-hundred-and-fifth Schottky diode. The cathode of the one-hundred-and-fifth Schottky diode is connected to the ground potential of the power tube.

[0027] The present invention also provides a SiC three-phase bridge drive circuit module based on SIP technology, comprising the above-mentioned SiC three-phase bridge drive circuit and a metal heat sink, a metal cover, an insulating housing, a lower substrate, and an upper substrate, wherein:

[0028] The metal heat sink is fixedly connected to the bottom of the insulating shell, and the metal cover is fixedly connected to the top of the insulating shell. The metal heat sink, the metal cover and the insulating shell on the side together form a module cavity. The lower substrate and the upper substrate are arranged inside the module cavity, wherein the lower substrate is welded to the metal heat sink by eutectic welding, and the edge of the upper substrate is fixedly mounted on the boss on the inner wall of the insulating shell;

[0029] The SiC MOSFET three-phase full-bridge power module is arranged on the lower substrate, and the power conversion circuit, four-channel isolated power supply, and six-way SiC MOSFET drive circuit are arranged on the upper substrate;

[0030] The circuits between the lower substrate and the upper substrate are electrically connected via pins;

[0031] The input and output pins of the module are led out through the insulating shell on the side.

[0032] Furthermore, a support column with a boss on the upper part is also provided in the inner cavity of the module. The bottom of the support column is fixed on the lower substrate and the top passes through the through hole of the upper substrate. The bottom surface of the upper substrate is placed on the upper surface of the boss of the support column to better support the upper substrate and prevent it from being deformed easily.

[0033] Furthermore, the metal heat sink material is nickel-plated copper, the metal cover material is 4J42 Kovar alloy, and the insulating shell material is plastic.

[0034] Furthermore, the lower substrate is an AMB ceramic substrate, and the upper substrate is a PCB substrate.

[0035] Furthermore, the bottom surface of each SiC MOSFET bare core in the SiC MOSFET three-phase full-bridge power module is welded to the lower AMB ceramic substrate using eutectic welding, and the remaining active chips are adhered to the upper PCB substrate using conductive adhesive.

[0036] Furthermore, the source of the SiC MOSFET tube on the lower AMB ceramic substrate is bonded using a 500 μm aluminum wire wedge, and the gate is bonded using a 150 μm aluminum wire wedge.

[0037] The beneficial effects of the present invention are:

[0038] 1. The present invention integrates the isolated power supply, drive circuit, and power module into the same circuit module, thereby reducing the space occupied by the SiC MOSFET driver. The subsequent stage can directly drive a high-voltage three-phase brushless DC motor without the need for other external circuits.

[0039] 2. Compared with other similar SiC MOSFET drive circuit products in the industry, the present invention is integrated based on system-in-package (SIP) technology, and has obvious advantages in product miniaturization, modularization, and lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic diagram of the circuit topology of an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of the structure of a four-channel isolated power supply circuit according to an embodiment of the present invention;

[0042] Figure 3 Schematic diagram of the structure of the U-phase high-side drive circuit in the six-way SiC MOSFET drive circuit according to an embodiment of the present invention;

[0043] Figure 4 Schematic diagram of the circuit structure of a SiC MOSFET three-phase full-bridge power module according to an embodiment of the present invention;

[0044] Figure 5 2. This is a cross-sectional view of a SiC three-phase bridge drive circuit module according to an embodiment of the present invention;

[0045] Figure 6 2. This is a front view of a SiC three-phase bridge drive circuit module according to an embodiment of the present invention;

[0046] Figure 7 1 is a top view of a SiC three-phase bridge drive circuit module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Figures 1 to 7 As shown, a specific embodiment of the present invention is a SiC three-phase bridge drive circuit module based on SIP technology, including a SiC three-phase bridge drive circuit, a metal heat sink 1 made of copper-nickel plated material, a metal cover 2 made of 4J42 Kovar alloy material, a plastic insulating shell 3, a lower substrate 4, and an upper substrate 5. The active chip bare core and passive components are packaged into the same module using SIP technology, wherein:

[0049] The lower substrate 4 is an AMB ceramic substrate, and the upper substrate 5 is a PCB substrate;

[0050] The metal heat dissipation plate 1 is fixedly connected to the bottom of the insulating shell 3, and the metal cover plate 2 is fixedly connected to the top of the insulating shell 3. The metal heat dissipation plate 1, the metal cover plate 2 and the insulating shell 3 on the side together enclose a module cavity, and the lower substrate 4 and the upper substrate 5 are arranged inside the module cavity, wherein the lower substrate 4 is welded to the metal heat dissipation plate 1 by eutectic welding, and the edge of the upper substrate 5 is fixedly installed on the boss on the inner wall of the insulating shell 3 and fixed with bolts; a support column 8 with a boss on the upper part is also provided in the module cavity, the bottom of the support column 8 is fixed on the lower substrate 4, and the top passes through the through hole of the upper substrate 5, and the bottom surface of the upper substrate 5 is placed on the upper surface of the boss of the support column 8.

[0051] The SiC three-phase bridge drive circuit includes a power conversion circuit, a four-channel isolated power supply, a six-way SiC MOSFET drive circuit, and a SiC MOSFET three-phase full-bridge power module, wherein the SiC MOSFET three-phase full-bridge power module is arranged on the lower substrate 4, and the power conversion circuit, the four-channel isolated power supply, and the six-way SiC MOSFET drive circuit are arranged on the upper substrate 5;

[0052] The circuits between the lower substrate 4 and the upper substrate 5 are electrically connected via pins 6;

[0053] The input and output pins 7 of the module are led out through the insulating shell 3 on the side.

[0054] In this embodiment, the bottom surface of each SiC MOSFET bare die in the SiC MOSFET three-phase full-bridge power module is eutectic-bonded to the underlying AMB ceramic substrate, while the remaining active chips are bonded to the upper PCB substrate using conductive adhesive. The source electrodes of the seven SiC MOSFETs (Q33, Q34, Q35, Q36, Q37, Q38, and Q39) on the underlying AMB ceramic substrate are bonded to the substrate's wiring using 500μm aluminum wire wedge bonding, while the gate electrodes are bonded to the substrate's wiring using 150μm aluminum wire wedge bonding.

[0055] In this embodiment:

[0056] The input terminal of the power conversion circuit is connected to the control power supply V CC The +12V power supply VCC12V output provides power input for the PWM controller N2 in the four-channel isolated power supply, and the +5V power supply VCC5V output provides power input for the six-way SiC MOSFET drive circuit. The power conversion circuit adopts the existing power supply design scheme in the industry, such as Figure 1 As shown in the figure, the power conversion circuit consists of a DCDC power chip, a low voltage drop linear regulator LDO and peripheral circuits. The DCDC power chip and peripheral circuits control the power supply V CCThe input typical value of +28V (input voltage range +12V to +75V) is converted to +12V for output. The low-dropout linear regulator LDO and peripheral circuits convert +12V to +5V for output.

[0057] The four-channel isolated power supply includes a PWM controller N2 and a four-channel isolation transformer T1, which is used to convert the control power supply V CC It is converted into four isolated power supplies: U-phase high-side isolated power supply PHU, V-phase high-side isolated power supply PHV, W-phase high-side isolated power supply PHW and low-side isolated power supply PL. Each isolated power supply includes +18V, -5V and GND zero potential, providing isolated power and GND zero potential for six SiCMOSFET drive circuits; the four-channel isolated power supply adopts a flyback isolated power supply solution.

[0058] like Figure 2 As shown in the figure, the specific structure of the four-channel isolated power supply is:

[0059] The power supply input pin VCC of the PWM controller N2 is connected to the +12V power supply VCC12V output by the power conversion circuit through the sixteenth resistor R16. The output pin OUT of the PWM controller N2 is connected to the gate of the second MOS transistor Q2 through the twenty-first resistor R21. The drain of the second MOS transistor Q2 is connected to the control power supply V CC They are respectively connected to both ends of the primary coil of the isolation transformer T1, the source of the second MOS transistor Q2 is connected to the ground potential GND through the thirty-first resistor R31, and is connected to the current detection input pin CS of the PWM controller N2 through the twenty-fourth resistor R24;

[0060] The isolation transformer T1 has four secondary coils, and the primary and secondary coils have opposite ends.

[0061] The first secondary coil of the isolation transformer T1 is connected in series with a first diode D1, a twelfth capacitor C12 is connected in parallel on the first parallel branch of the first diode D1, a ninth resistor R9 is connected in parallel on the second parallel branch, an eighth capacitor C8 and a fifteenth capacitor C15 are connected in series on the third parallel branch, and a seventh resistor R7 and a third voltage-stabilizing diode D3 are connected in series on the fourth parallel branch. The connection point between the eighth capacitor C8 and the fifteenth capacitor C15 is connected to the connection point between the seventh resistor R7 and the negative electrode of the third voltage-stabilizing diode D3 as the zero potential GND-PHU of the U-phase high-side isolated power supply, the negative electrode of the first diode D1 serves as the +18V output terminal 18V-PHU of the U-phase high-side isolated power supply, and the positive electrode of the third voltage-stabilizing diode D3 serves as the -5V output terminal -5V-PHU of the U-phase high-side isolated power supply;

[0062] The second secondary coil of the isolation transformer T1 is connected in series with a sixth diode D6, a seventeenth capacitor C17 is connected in parallel to the first parallel branch of the sixth diode D6, a fourteenth resistor R14 is connected in parallel to the second parallel branch thereof, a sixteenth capacitor C16 and a nineteenth capacitor C19 are connected in series to the third parallel branch thereof, a thirteenth resistor R13 and a tenth voltage-stabilizing diode D10 are connected in series to the fourth parallel branch thereof, a connection point between the sixteenth capacitor C16 and the nineteenth capacitor C19 is connected to a connection point between the thirteenth resistor R13 and the negative electrode of the tenth voltage-stabilizing diode D10, serving as the zero potential GND-PHV of the V-phase high-side isolated power supply, the negative electrode of the sixth diode D6 serves as the +18V output terminal 18V-PHV of the V-phase high-side isolated power supply, and the positive electrode of the tenth voltage-stabilizing diode D10 serves as the -5V output terminal -5V-PHV of the V-phase high-side isolated power supply;

[0063] The third secondary coil of the isolation transformer T1 is connected in series with an eleventh diode D11, a twenty-ninth capacitor C29 is connected in parallel to a first parallel branch of the eleventh diode D11, a thirty-third resistor R33 is connected in parallel to a second parallel branch thereof, a twenty-fifth capacitor C25 and a thirty-fifth capacitor C35 are connected in series to a third parallel branch thereof, a twenty-ninth resistor R29 and a thirteenth voltage-stabilizing diode D13 are connected in series to a fourth parallel branch thereof, a connection point between the twenty-fifth capacitor C25 and the thirty-fifth capacitor C35 is connected to a connection point between the twenty-ninth resistor R29 and the cathode of the thirteenth voltage-stabilizing diode D13, serving as a zero potential GND-PHW of a W-phase high-side isolated power supply, the cathode of the eleventh diode D11 serves as a +18V output terminal 18V-PHW of the W-phase high-side isolated power supply, and the anode of the thirteenth voltage-stabilizing diode D13 serves as a -5V output terminal -5V-PHW of the W-phase high-side isolated power supply;

[0064] A fourteenth diode D14 is connected in series to the fourth secondary coil of the isolation transformer T1, a thirty-ninth capacitor C39 is connected in parallel to the first parallel branch of the fourteenth diode D14, a forty-eighth resistor R48 is connected in parallel to the second parallel branch thereof, a thirty-eighth capacitor C38 and a forty-first capacitor C41 are connected in series to the third parallel branch thereof, a forty-sixth resistor R46 and a sixteenth voltage-stabilizing diode D16 are connected in series to the fourth parallel branch thereof, a connection point between the thirty-eighth capacitor C38 and the forty-first capacitor C41 is connected to a connection point between the forty-sixth resistor R46 and the cathode of the sixteenth voltage-stabilizing diode D16, serving as a low-side isolated power supply zero potential GND-PL, a cathode of the fourteenth diode D14 serving as a low-side isolated power supply +18V output terminal 18V-PL, and a positive electrode of the sixteenth voltage-stabilizing diode D16 serving as a low-side isolated power supply -5V output terminal -5V-PL;

[0065] Two ends of a sixty-seventh sampling resistor R67 and a seventy-seventh sampling resistor R77 connected in series are respectively connected to the U-phase high-side isolated power supply +18V output terminal 18V-PHU and the U-phase high-side isolated power supply -5V output terminal -5V-PHU. The connection point between the sixty-seventh sampling resistor R67 and the seventy-seventh sampling resistor R77 is connected to the REF reference electrode of the voltage reference source U1. The anode of the voltage reference source U1 is connected to the U-phase high-side isolated power supply -5V output terminal -5V-PHU, and the cathode is connected to the U-phase high-side isolated power supply +18V output terminal 18V-PHU via the sixty-third bias resistor R63.

[0066] The anode of the optocoupler N4 diode is connected to the U-phase high-side isolated power supply +18V output terminal 18V-PHU through the fifty-seventh resistor R57, and the cathode is connected to the cathode of the voltage reference source U1; the emitter of the optocoupler N4 transistor is connected to the ground potential GND through the sixty-ninth resistor R69, the collector is connected to the inverting input pin COMP of the PWM controller N2, and the collector is also connected to the internal reference voltage output pin REF of the PWM controller N2 through the thirty-seventh resistor R37.

[0067] In this embodiment, the PWM controller N2 uses a chip of model HYX1800, and the voltage reference source U1 uses a chip of model HYW431.

[0068] The four-channel isolated power supply uses PWM controller N2 as the main chip, generating a PWM wave with an adjustable duty cycle to control the on / off switching of the second MOS transistor Q2 on the primary side of the isolation transformer T1, thereby generating a rectangular wave voltage on the primary side of the isolation transformer T1. The four-channel secondary side of the isolation transformer T1 and its peripheral circuits generate four corresponding +23V voltage outputs. Through the action of capacitors and Zener diodes D3, D10, D13, and D16, four isolated power supplies are generated, including +18V, GND zero potential, and -5V. The isolated voltage generated on the secondary side is fed back to the PWM controller N2 through the voltage reference source U1 and the optocoupler N4. If the secondary side voltage is disturbed, the output duty cycle of the PWM controller N2 is changed, thereby adjusting the secondary side output voltage to maintain stability.

[0069] The six-way SiC MOSFET drive circuit is used to convert the six PWM control signals output by the motor control unit, namely, the U-phase high-side control signal IN+_UH, the U-phase low-side control signal IN+_UL, the V-phase high-side control signal IN+_VH, the V-phase low-side control signal IN+_VL, the W-phase high-side control signal IN+_WH, and the W-phase low-side control signal IN+_WL, into six isolated drive signals, namely, the U-phase high-side isolated drive signal PWM_UH, the U-phase low-side isolated drive signal PWM_UL, the V-phase high-side isolated drive signal PWM_VH, the V-phase low-side isolated drive signal PWM_VL, the W-phase high-side isolated drive signal PWM_WH, and the W-phase low-side isolated drive signal PWM_WL; wherein the U-phase high-side, V-phase high-side, and W-phase high-side drive circuits use the U-phase high-side isolated power supply PHU, the V-phase high-side isolated power supply PHV, and the W-phase high-side isolated power supply PHW, respectively, and the U-phase low-side, V-phase low-side, and W-phase low-side drive circuits all use the low-side isolated power supply PL. The six-way SiC MOSFET drive circuit adopts the industry's existing technology drive solution. Figure 3 The structure of one of the U-phase high-side drive circuits is shown as an example. It consists of a single-channel isolated driver chip U22 with negative voltage drive, a protection circuit, and peripheral circuits. Isolated driver chip U22 uses the HYD6601 chip. The U-phase high-side control signal IN+_UH, output by the motor control unit, is input to the INP+ pin of isolated driver chip U22. The +5V generated by the power conversion circuit is input to its VCC1 pin. A four-channel isolated power supply provides isolated power to the driver circuit and the U-phase high-side isolated power supply zero potential GND-PHU. The 18V-PHU of the U-phase high-side isolated power supply is input to its VCC2 pin, and the -5V-PHU is input to its VEE2 pin. Isolated driver chip U22 outputs the U-phase high-side isolated drive signal PWM_UH. This embodiment has a total of six SiC MOSFET drive circuits, which output six isolated PWM drive signals PWM_UH, PWM_UL, PWM_VH, PWM_VL, PWM_WH, and PWM_WL to ensure that the SiC MOSFET three-phase full-bridge power module can be reliably turned on and off.

[0070] The SiC MOSFET three-phase full-bridge power module is used to turn on the six SiC MOSFETs in sequence under the control of the six isolated drive signals, and output U-phase, V-phase, and W-phase drive currents to drive the three-phase brushless DC motor. Figure 4As shown in the figure, the full-bridge power circuit of the SiC MOSFET three-phase full-bridge power module consists of six SiC MOSFETs, Q33, Q34, Q35, Q37, Q38, and Q39, and peripheral components. The specific structure adopts the full-bridge power module solution of the existing technology in the industry, among which Q33, Q34, and Q35 serve as the power tubes of the upper bridge arm, and PWM_UH, PWM_VH, and PWM_WH serve as their gate drive signals respectively. Q37, Q38, and Q39 serve as the power tubes of the lower bridge arm, and PWM_UL, PWM_VL, and PWM_WL serve as their gate drive signals respectively.

[0071] The rated input of the SiC MOSFET three-phase full-bridge power module of this embodiment is 540V / 40A, and can reach a maximum of 1200V / 80A.

[0072] The SiC MOSFET three-phase full-bridge power module is further provided with a thermistor R71 for temperature monitoring. The positive terminal RTC+ and the negative terminal RTC- of the thermistor R71 are connected to the motor control unit.

[0073] The SiC MOSFET three-phase full-bridge power module also has a discharge circuit, and the specific structure of the discharge circuit is as follows:

[0074] The gate of the thirty-sixth SiC MOSFET tube Q36 is connected to the discharge control signal PWM_ZD output by the motor control unit, the drain thereof is connected to the power supply VS via the one hundred and third SiC Schottky diode D103, and the source thereof is connected to the power supply ground PGND;

[0075] A 174th capacitor 174 and a 102nd resistor R102 are connected in series between the drain and source of the 36th SiC MOSFET Q36. The connection point between the 174th capacitor 174 and the 102nd resistor R102 is connected to the anode of the 105th Schottky diode D105. The cathode of the 105th Schottky diode D105 is connected to the power transistor ground potential PGND. The 36th SiC MOSFET Q36 and the Schottky diode D105 form an energy dissipation circuit. Figure 4 As shown, when the SiC three-phase bridge drive circuit needs to quickly discharge energy, the motor control unit sends a control signal to turn on the thirty-sixth SiC MOSFET tube Q36 corresponding to the B-phase output, thereby quickly discharging the energy accumulated in the high-voltage bus.

[0076] The overall operation process of the SiC three-phase bridge drive circuit in this embodiment is as follows:

[0077] The +28V control power supply is converted to +12V and +5V via a power conversion circuit. The +12V voltage provides the power input for the PWM controller N2, while the +5V voltage provides the power input for the six-channel SiC MOSFET driver circuit. The four-channel isolated power supply, consisting primarily of the PWM controller N2 and the four-channel isolation transformer T1, converts the +28V control power supply into four isolated power supplies (each including +18V, -5V, and GND), providing isolated power and GND for the six SiC MOSFET driver circuits. The six-channel SiC MOSFET driver circuits utilize an isolated driver chip and peripheral circuitry to convert the PWM control signals input from the motor control unit into isolated drive signals, thereby driving the SiC MOSFETs. The SiC MOSFET three-phase full-bridge power module is used to drive the three-phase brushless DC motor.

[0078] The technical parameters of the SiC three-phase bridge drive circuit module of this embodiment are shown in the following table:

[0079] Serial number Technical Parameters Technical indicators Remark 1 <![CDATA[Control power input voltage V CC > Rated voltage +28V, input voltage range +12V~+75V 2 Power supply input voltage VS Rated voltage +540V, maximum +1200V 3 Power output current Rated current 40A, maximum 80A 4 Input signal PWM square wave signal (voltage 5Vpp, center voltage 2.5V) 5 Switching frequency Typical value 200KHz, range 50KHz~500KHz 6 Shell size requirements 50mm×90mm×20mm

[0080] The pinout of the SiC three-phase bridge drive circuit module in this embodiment is shown in the following table:

[0081]

[0082]

Claims

1. A SiC three-phase bridge drive circuit, characterized in that: It includes power conversion circuit, four-channel isolated power supply, six-way SiC MOSFET drive circuit, and SiC MOSFET three-phase full-bridge power module, including: The input terminal of the power conversion circuit is connected to the control power supply (V CC ), its output +12V power supply (VCC12V) provides power input for the PWM controller in the four-channel isolated power supply, and its output +5V power supply (VCC5V) provides power input for the six-channel SiC MOSFET drive circuit; The four-channel isolated power supply includes a PWM controller and a four-channel isolation transformer for converting the control power supply (V CC ) is converted into four isolated power supplies: U-phase high-side isolated power supply (PHU), V-phase high-side isolated power supply (PHV), W-phase high-side isolated power supply (PHW) and low-side isolated power supply (PL). Each isolated power supply includes +18V, -5V and GND zero potential, providing isolated power and GND zero potential for six SiC MOSFET drive circuits; The six-way SiC MOSFET drive circuit is used to convert the six PWM control signals output by the motor control unit, namely, the U-phase high-side control signal (IN+_UH), the U-phase low-side control signal (IN+_UL), the V-phase high-side control signal (IN+_VH), the V-phase low-side control signal (IN+_VL), the W-phase high-side control signal (IN+_WH), and the W-phase low-side control signal (IN+_WL), into the U-phase high-side isolated drive signal (PWM_UH), the U-phase low-side isolated drive signal (PWM_UL), the V-phase high-side isolated drive signal (PWM_VH), the V-phase low-side isolated drive signal (IN+_VL), and the W-phase high-side isolated drive signal (IN+_WH). The U-phase high side, V-phase high side, and W-phase high side drive circuits use the U-phase high side isolated power supply (PHU), the V-phase high side isolated power supply (PHV), and the W-phase high side isolated power supply (PHW), respectively, and the U-phase low side, V-phase low side, and W-phase low side drive circuits all use the low side isolated power supply (PL); The SiC MOSFET three-phase full-bridge power module is used to turn on the six SiC MOSFETs in a time sequence under the control of the six isolated drive signals, and output U-phase, V-phase, and W-phase drive currents to drive the three-phase brushless DC motor; The SiC MOSFET three-phase full-bridge power module is further provided with a thermistor (R71), and the positive end (RTC+) and the negative end (RTC-) of the thermistor (R71) are used to be connected to the motor control unit.

2. The SiC three-phase bridge drive circuit according to claim 1, characterized in that: The control power supply (V CC ) has a voltage input range of +12V to +75V and a rated input voltage of +28V.

3. The SiC three-phase bridge drive circuit according to claim 1, characterized in that: The specific structure of the four-channel isolated power supply is: The power supply input pin (VCC) of the PWM controller is connected to the +12V power supply (VCC12V) output by the power conversion circuit through the sixteenth resistor (R16), and the output pin (OUT) of the PWM controller is connected to the gate of the second MOS tube (Q2) through the twenty-first resistor (R21), and the drain of the second MOS tube (Q2) and the control power supply (V CC ) are respectively connected to both ends of the primary coil of the isolation transformer (T1), the source of the second MOS transistor (Q2) is connected to the ground potential (GND) through a thirty-first resistor (R31), and is connected to the current detection input pin (CS) of the PWM controller through a twenty-fourth resistor (R24); The isolation transformer (T1) has four secondary coils, and the primary coil and the secondary coil have opposite ends. The first secondary winding of the isolation transformer (T1) is connected in series with a first diode (D1); a twelfth capacitor (C12) is connected in parallel to a first parallel branch of the first diode (D1); a ninth resistor (R9) is connected in parallel to a second parallel branch of the first diode (D1); an eighth capacitor (C8) and a fifteenth capacitor (C15) are connected in series to a third parallel branch of the first diode (D1); a seventh resistor (R7) and a third voltage-stabilizing diode (D3) are connected in series to a fourth parallel branch of the first diode (D1); a connection point between the eighth capacitor (C8) and the fifteenth capacitor (C15) is connected to a connection point between the seventh resistor (R7) and the negative electrode of the third voltage-stabilizing diode (D3), serving as a zero potential (GND-PHU) of a U-phase high-side isolated power supply; the negative electrode of the first diode (D1) serves as a +18V output terminal (18V-PHU) of a U-phase high-side isolated power supply; and a positive electrode of the third voltage-stabilizing diode (D3) serves as a -5V output terminal (-5V-PHU) of a U-phase high-side isolated power supply. The second secondary winding of the isolation transformer (T1) is connected in series with a sixth diode (D6), a first parallel branch of the sixth diode (D6) is connected in parallel with a seventeenth capacitor (C17), a second parallel branch of the sixth diode (D6) is connected in parallel with a fourteenth resistor (R14), a third parallel branch of the sixth diode (D6) is connected in series with a sixteenth capacitor (C16) and a nineteenth capacitor (C19), a fourth parallel branch of the sixth diode (D6) is connected in series with a thirteenth resistor (R13) and a tenth voltage stabilizing diode (D10), and the sixteenth capacitor (C16) and the nineteenth capacitor (C19) are connected in series. The connection point between the capacitor (C16) and the nineteenth capacitor (C19) is connected to the connection point between the thirteenth resistor (R13) and the negative electrode of the tenth voltage stabilizing diode (D10), serving as the zero potential (GND-PHV) of the V-phase high-side isolated power supply, the negative electrode of the sixth diode (D6) serves as the +18V output terminal (18V-PHV) of the V-phase high-side isolated power supply, and the positive electrode of the tenth voltage stabilizing diode (D10) serves as the -5V output terminal (-5V-PHV) of the V-phase high-side isolated power supply; The third secondary winding of the isolation transformer (T1) is connected in series with an eleventh diode (D11), a twenty-ninth capacitor (C29) is connected in parallel to a first parallel branch of the eleventh diode (D11), a thirty-third resistor (R33) is connected in parallel to a second parallel branch, a twenty-fifth capacitor (C25) and a thirty-fifth capacitor (C35) are connected in series to a third parallel branch, a twenty-ninth resistor (R29) and a thirteenth voltage-stabilizing diode (D13) are connected in series to a fourth parallel branch, and the second The connection point between the fifteenth capacitor (C25) and the thirty-fifth capacitor (C35) is connected to the connection point between the twenty-ninth resistor (R29) and the cathode of the thirteenth voltage-stabilizing diode (D13), serving as the zero potential (GND-PHW) of the W-phase high-side isolated power supply, the cathode of the eleventh diode (D11) serving as the +18V output end (18V-PHW) of the W-phase high-side isolated power supply, and the anode of the thirteenth voltage-stabilizing diode (D13) serving as the -5V output end (-5V-PHW) of the W-phase high-side isolated power supply; The fourth secondary winding of the isolation transformer (T1) is connected in series with a fourteenth diode (D14); a first parallel branch of the fourteenth diode (D14) is connected in parallel with a thirty-ninth capacitor (C39); a second parallel branch of the fourteenth diode (D14) is connected in parallel with a forty-eighth resistor (R48); a third parallel branch of the fourteenth diode (D14) is connected in series with a thirty-eighth capacitor (C38) and a forty-first capacitor (C41); and a fourth parallel branch of the fourteenth diode (D14) is connected in series with a forty-sixth resistor (R46) and a sixteenth voltage stabilizing diode (D16). The connection point between the thirty-eighth capacitor (C38) and the forty-first capacitor (C41) is connected to the connection point between the forty-sixth resistor (R46) and the cathode of the sixteenth voltage-stabilizing diode (D16), serving as a low-side isolated power supply zero potential (GND-PL); the cathode of the fourteenth diode (D14) serves as a low-side isolated power supply +18V output terminal (18V-PL); and the anode of the sixteenth voltage-stabilizing diode (D16) serves as a low-side isolated power supply -5V output terminal (-5V-PL); Two ends of a sixty-seventh sampling resistor (R67) and a seventy-seventh sampling resistor (R77) connected in series are respectively connected to the U-phase high-side isolated power supply +18V output terminal (18V-PHU) and the U-phase high-side isolated power supply -5V output terminal (-5V-PHU); a connection point between the sixty-seventh sampling resistor (R67) and the seventy-seventh sampling resistor (R77) is connected to the REF reference electrode of the voltage reference source (U1); an anode of the voltage reference source (U1) is connected to the U-phase high-side isolated power supply -5V output terminal (-5V-PHU), and a cathode is connected to the U-phase high-side isolated power supply +18V output terminal (18V-PHU) via a sixty-third bias resistor (R63); The anode of the optocoupler (N4) diode is connected to the U-phase high-side isolated power supply +18V output terminal (18V-PHU) through the fifty-seventh resistor (R57), and the cathode is connected to the cathode of the voltage reference source (U1); the emitter of the optocoupler (N4) transistor is connected to the ground potential (GND) through the sixty-ninth resistor (R69), the collector is connected to the inverting input pin (COMP) of the PWM controller, and the collector is also connected to the internal reference voltage output pin (REF) of the PWM controller through the thirty-seventh resistor (R37).

4. The SiC three-phase bridge drive circuit according to claim 1, characterized in that: The SiC MOSFET three-phase full-bridge power module also has a discharge circuit, and the specific structure of the discharge circuit is as follows: The gate of the thirty-sixth SiC MOSFET tube (Q36) is connected to the discharge control signal (PWM_ZD) output by the motor control unit, the drain thereof is connected to the power supply (VS) via the one hundred and third SiC Schottky diode (D103), and the source thereof is connected to the power supply ground (PGND); A one-hundred-and-seventy-fourth capacitor (174) and a one-hundred-and-second resistor (R102) are connected in series between the drain and source of the thirty-sixth SiC MOSFET tube (Q36); a connection point between the one-hundred-and-seventy-fourth capacitor (174) and the one-hundred-and-second resistor (R102) is connected to the positive electrode of the one-hundred-and-fifth Schottky diode (D105); and a negative electrode of the one-hundred-and-fifth Schottky diode (D105) is connected to the power tube ground potential (PGND).

5. A SiC three-phase bridge drive circuit module based on SIP technology, characterized in that: The invention comprises a SiC three-phase bridge drive circuit as claimed in any one of claims 1 to 4, a metal heat sink (1), a metal cover (2), an insulating shell (3), a lower substrate (4), and an upper substrate (5), wherein: The metal heat dissipation plate (1) is fixedly connected to the bottom of the insulating shell (3), the metal cover plate (2) is fixedly connected to the top of the insulating shell (3), the metal heat dissipation plate (1), the metal cover plate (2) and the insulating shell (3) on the side together enclose to form a module cavity, the lower substrate (4) and the upper substrate (5) are arranged inside the module cavity, wherein the lower substrate (4) is welded to the metal heat dissipation plate (1) by eutectic welding, and the edge of the upper substrate (5) is fixedly mounted on the boss on the inner wall of the insulating shell (3); The SiC MOSFET three-phase full-bridge power module is arranged on a lower substrate (4), and the power conversion circuit, four-channel isolated power supply, and six-way SiC MOSFET drive circuit are arranged on an upper substrate (5); The circuits between the lower substrate (4) and the upper substrate (5) are electrically connected via pins (6); Each input and output pin (7) of the module is led out through the insulating shell (3) on the side.

6. The SiC three-phase bridge drive circuit module based on SIP technology according to claim 5, characterized in that: A support column (8) with a boss on the upper portion is also provided in the module inner cavity. The bottom of the support column (8) is fixed on the lower substrate (4), and the top passes through the through hole of the upper substrate (5). The bottom surface of the upper substrate (5) is placed on the upper surface of the boss of the support column (8).

7. The SiC three-phase bridge drive circuit module based on SIP technology according to claim 5, characterized in that: The material of the metal heat dissipation plate (1) is nickel-plated copper, the material of the metal cover plate (2) is 4J42 Kovar alloy, and the material of the insulating shell (3) is plastic.

8. The SiC three-phase bridge drive circuit module based on SIP technology according to claim 5, characterized in that: The lower substrate (4) is an AMB ceramic substrate, and the upper substrate (5) is a PCB substrate.

9. The SiC three-phase bridge drive circuit module based on SIP technology according to claim 8, characterized in that: The bottom surface of each SiC MOSFET bare core in the SiC MOSFET three-phase full-bridge power module is welded to the lower AMB ceramic substrate using eutectic welding, and the remaining active chips are adhered to the upper PCB substrate using conductive adhesive.

10. The SiC three-phase bridge drive circuit module based on SIP technology according to claim 8, characterized in that: The source of the SiC MOSFET tube on the lower AMB ceramic substrate is bonded with a 500 μm aluminum wire wedge, and the gate is bonded with a 150 μm aluminum wire wedge.

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