SiC three-phase bridge driving 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 technical field of integrated circuits, and the SiC three-phase bridge drive circuit module comprises a SiC three-phase bridge drive circuit, a metal heat dissipation plate, a metal cover plate, an insulating shell, a lower substrate and an upper substrate. The SiC three-phase bridge driving circuit comprises a power conversion circuit, a four-channel isolation power supply, a six-path SiC MOSFET driving 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, the four-channel isolation power supply and the six-path SiC MOSFET driving circuit are arranged on the upper substrate. According to the invention, a systematic packaging SIP technology is adopted, an active chip and a passive device are packaged in the same module, a rear stage can directly drive a high-voltage three-phase brushless direct current motor, and miniaturization, modularization and light weight of SiC MOSFET driving are realized.

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) and belongs to the wide bandgap (WBG) family of materials. Its physical bonds are very strong, giving the semiconductor high mechanical, chemical and thermal stability. MOSFETs made of SiC have the following advantages: reduced power loss, high-temperature operation, high-speed switching operation, excellent heat dissipation, and shorter reverse recovery time. Since SiC MOSFETs can operate at higher frequencies and temperatures without affecting reliability, they are widely used in fields including converters, inverters, power supplies, battery chargers, and motor control systems.

[0003] Although SiC MOSFET has higher operating capacity, the SiC MOSFET driving circuit is different from the traditional Si-based MOSFET driving circuit and is more complicated. SiC MOSFET is used in high-voltage and high-power power supply applications. In order to avoid excessive crosstalk from the power part to the previous stage, an isolated power supply is required; in order to ensure the reliable shutdown of SiC MOSFET, a negative voltage drive is required; SiC MOSFET is used in high-voltage and high-power applications, and its voltage and current overshoot are large, so a variety of protection circuits are required.

[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 the SiC power module. However, based on this structure, an external drive circuit is required to drive the SiC chip.

[0005] Patent CN202220961577 "A SiC MOSFET drive and protection self-reset circuit for V2G vehicle-mounted converter" proposes a SiC drive circuit and integrates a protection circuit. Based on this patent, a half-bridge SiC module can be driven. However, this patent is not comprehensive in the field of SiC drive. On the one hand, this patent can only drive a half-bridge SiC module, while in actual engineering, a three-phase full-bridge SiC module is more common; on the other hand, this patent only integrates the drive chip and peripheral circuits, and does not integrate an isolated power supply, so an external isolated power supply is required to complete the drive of the SiC module.

[0006] At present, the industry usually develops the isolated power supply, drive circuit, and power module separately for SiC MOSFET drivers, which makes the system too complicated and occupies too much space. Therefore, the requirements for SiC MOSFET drivers to miniaturize, modularize, and lighten the system have become inevitable. 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 an isolated power supply, a drive circuit, and a 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 systematic packaging SIP technology is adopted to package the active chip (bare core) and the passive device into the same module, thereby realizing the miniaturization, modularization and lightweight of the SiC MOSFET drive.

[0008] In order to achieve the above purpose, the technical solution adopted by the present invention is: 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 end of the power conversion circuit is connected to the control power supply, and 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-way SiC MOSFET drive circuit; the power conversion circuit adopts the existing power design scheme in the industry.

[0010] The four-channel isolated power supply includes a PWM controller and a four-channel isolation transformer, which are used to convert the control power supply into four isolated power supplies, namely, 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 supply 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, the U-phase low-side control signal, the V-phase high-side control signal, the V-phase low-side control signal, the W-phase high-side control signal, and the 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 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 also 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] The power supply input pin of the PWM controller is connected to the +12V power supply output by the power conversion circuit through a sixteenth resistor, the output pin of the PWM controller is connected to the gate of the second MOS tube through a twenty-first resistor, the drain of the second MOS tube and the control power supply are respectively connected to the two ends of the primary coil of the isolation transformer, the source of the second MOS tube is connected to the ground potential through a thirty-first resistor, and is connected to the current detection input pin of the PWM controller through a twenty-fourth resistor;

[0017] The isolation transformer has four secondary coils, and the primary coil and the secondary coil have opposite ends with the same name;

[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 zener 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 cathode of the third zener diode as the zero potential of the U-phase high-side isolation power supply, the cathode of the first diode serves as the +18V output end of the U-phase high-side isolation power supply, and the anode of the third zener diode serves as the -5V output end of the U-phase high-side isolation 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 cathode of the tenth voltage-stabilizing diode, serving as the zero potential of the V-phase high-side isolation power supply, the cathode of the sixth diode serves as the +18V output terminal of the V-phase high-side isolation power supply, and the anode of the tenth voltage-stabilizing diode serves as the -5V output terminal of the V-phase high-side isolation power supply;

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

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

[0022] Two ends of the sixty-seventh sampling resistor and the seventy-seventh sampling resistor connected in series are respectively connected to the U-phase high-side isolated power supply +18V output end and the U-phase high-side isolated power supply -5V output end, 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 U-phase high-side isolated power supply -5V output end, and the cathode is connected to the U-phase high-side isolated power supply +18V output end 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 tube is connected to the discharge control signal output by the motor control unit, the drain thereof is connected to the power supply through the one hundred and third SiC Schottky diode, and the source thereof is connected to the power supply ground;

[0026] The one-hundred-and-seventy-fourth capacitor and the 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 positive electrode of the one-hundred-and-fifth Schottky diode, and the negative electrode 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 SiC three-phase bridge drive circuit as described above 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, 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 enclose 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 a 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, the four-channel isolated power supply, and the six-way SiC MOSFET drive circuit are arranged on the upper substrate;

[0030] The circuit between the lower substrate and the upper substrate is 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 module cavity. 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 material of the metal heat sink is nickel-plated copper, the material of the metal cover plate is 4J42 Kovar alloy, and the material of the insulating shell 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 by eutectic welding, and the remaining active chips are adhered to the upper PCB substrate by conductive adhesive.

[0036] Furthermore, the source of the SiC MOSFET tube on the lower AMB ceramic substrate is bonded by a 500 μm aluminum wire wedge, and the gate is bonded by 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, driving circuit, and power module into the same circuit module, thereby reducing the space occupied by the SiCMOSFET driver. The rear stage can directly drive a high-voltage three-phase brushless DC motor without the need for external other circuits;

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

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

[0041] Figure 2 It 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 1 is a schematic diagram of the structure of a U-phase high-side drive circuit in a six-way SiC MOSFET drive circuit according to an embodiment of the present invention;

[0043] Figure 4 1 is a 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 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 1 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] Figure 1 to Figure 7 It is shown that 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 devices 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 sink 1 is fixedly connected to the bottom of the insulating shell 3, and the metal cover 2 is fixedly connected to the top of the insulating shell 3. The metal heat sink 1, the metal cover 2 and the insulating shell 3 on the side together enclose a module cavity, and a lower substrate 4 and an upper substrate 5 are arranged inside the module cavity, wherein the lower substrate 4 is welded to the metal heat sink 1 by eutectic welding, and the edge of the upper substrate 5 is fixedly installed on the boss of 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 arranged 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 circuit between the lower substrate 4 and the upper substrate 5 is electrically connected via the pins 6;

[0053] Each input and output pin 7 of the module is led out through the insulating housing 3 on the side.

[0054] In this embodiment, 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 by eutectic welding, and the remaining active chips are pasted to the upper PCB substrate by conductive adhesive. Among them, the source of the seven SiC MOSFET tubes Q33, Q34, Q35, Q36, Q37, Q38, and Q39 on the lower AMB ceramic substrate is bonded to the wiring of the substrate by 500μm aluminum wire wedge, and the gate is bonded to the wiring of the substrate by 150μm aluminum wire wedge.

[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 outputted by it provides power input for the PWM controller N2 in the four-channel isolated power supply, and the +5V power supply VCC5V outputted by it 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 the 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, and 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, namely 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 supply 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, and the output pin OUT of the PWM controller N2 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 is connected to the control power supply V CC The two ends of the primary coil of the isolation transformer T1 are connected respectively, the source of the second MOS tube 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 secondary coil of the isolation transformer T1 has four paths, and the primary coil and the secondary coil have opposite ends with the same name;

[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, a seventh resistor R7 and a third voltage zener diode D3 are connected in series on the fourth parallel branch, 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 cathode of the third voltage zener diode D3, serving as a zero potential GND-PHU of a U-phase high-side isolated power supply, a cathode of the first diode D1 serves as a +18V output terminal 18V-PHU of a U-phase high-side isolated power supply, and a cathode of the third voltage zener diode D3 serves as a -5V output terminal -5V-PHU of a 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, the first parallel branch of the sixth diode D6 is connected in parallel with a seventeenth capacitor C17, the second parallel branch is connected in parallel with a fourteenth resistor R14, the third parallel branch is connected in series with a sixteenth capacitor C16 and a nineteenth capacitor C19, the fourth parallel branch is connected in series with a thirteenth resistor R13 and a tenth voltage zener diode D10, the connection point between the sixteenth 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 zener diode D10, as the zero potential GND-PHV of the V-phase high-side isolation power supply, the negative electrode of the sixth diode D6 serves as the V-phase high-side isolation power supply +18V output terminal 18V-PHV, and the positive electrode of the tenth voltage zener diode D10 serves as the V-phase high-side isolation power supply -5V output terminal -5V-PHV;

[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 on the first parallel branch of the eleventh diode D11, a thirty-third resistor R33 is connected in parallel on the second parallel branch, a twenty-fifth capacitor C25 and a thirty-fifth capacitor C35 are connected in series on the third parallel branch, a twenty-ninth resistor R29 and a thirteenth voltage-stabilizing diode D13 are connected in series on the fourth parallel branch, 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, a cathode of the eleventh diode D11 serves as a +18V output terminal 18V-PHW of a W-phase high-side isolated power supply, and a positive electrode of the thirteenth voltage-stabilizing diode D13 serves as a -5V output terminal -5V-PHW of a W-phase high-side isolated power supply;

[0064] The fourth secondary coil of the isolation transformer T1 is connected in series with a fourteenth diode D14, the first parallel branch of the fourteenth diode D14 is connected in parallel with a thirty-ninth capacitor C39, the second parallel branch thereof is connected in parallel with a forty-eighth resistor R48, the third parallel branch thereof is connected in series with a thirty-eighth capacitor C38 and a forty-first capacitor C41, the fourth parallel branch thereof 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, as a low-side isolation power supply zero potential GND-PL, the cathode of the fourteenth diode D14 is used as a low-side isolation power supply +18V output terminal 18V-PL, and the anode of the sixteenth voltage-stabilizing diode D16 is used as a low-side isolation power supply -5V output terminal -5V-PL;

[0065] Two ends of the sixty-seventh sampling resistor R67 and the 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 through 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 the PWM controller N2 as the main chip to generate a PWM wave with an adjustable duty cycle to control the on and off of the second MOS tube 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 the peripheral circuits generate four +23V voltage outputs accordingly, and then through the capacitors and voltage-stabilizing 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 output voltage of the secondary side to keep it stable.

[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 channels, namely the U-phase high-side drive circuit, is shown as an example. It is composed of a single-channel isolation drive chip U22 with negative voltage drive, a protection circuit and a peripheral circuit, wherein the isolation drive chip U22 uses a chip model HYD6601. The U-phase high-side control signal IN+_UH output by the motor control unit is input to the INP+ pin of the isolation drive chip U22, and the +5V generated by the power conversion circuit is input to its VCC1 pin. The four-channel isolation power supply provides the drive circuit with an isolated power supply and the U-phase high-side isolation power supply zero potential GND-PHU, wherein the 18V-PHU of the U-phase high-side isolation power supply is input to its VCC2 pin, and the -5V-PHU is input to its VEE2 pin. The isolation drive chip U22 outputs the U-phase high-side isolation 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, ensuring that the SiCMOSFET 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, the full-bridge power circuit part of the SiC MOSFET three-phase full-bridge power module is composed 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 are used as power tubes of the upper bridge arm, and PWM_UH, PWM_VH, and PWM_WH are used as their gate drive signals respectively, and Q37, Q38, and Q39 are used as power tubes of the lower bridge arm, and PWM_UL, PWM_VL, and PWM_WL are used 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 up to 1200V / 80A.

[0072] The SiC MOSFET three-phase full-bridge power module is also provided with a thermistor R71 for temperature monitoring, and the positive terminal RTC+ and the negative terminal RTC- of the thermistor R71 are used to be 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:

[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 through the one hundred and third SiC Schottky diode D103, and the source thereof is connected to the power supply ground PGND;

[0075] The one hundred and seventy-fourth capacitor 174 and the one hundred and second resistor R102 are connected in series between the drain and source of the thirty-sixth SiC MOSFET tube Q36, the 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 the negative electrode of the one hundred and fifth Schottky diode D105 is connected to the power tube ground potential PGND. The thirty-sixth SiC MOSFET tube Q36 and the Schottky diode D105 form an energy discharge circuit, such as Figure 4 As shown, when the SiC three-phase bridge drive circuit needs to discharge energy quickly, 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 into +12V and +5V through the power conversion circuit, where +12V provides power input for the PWM controller N2, and +5V provides power input for the six-way SiC MOSFET drive circuit. The four-channel isolated power supply mainly includes the PWM controller N2 and the four-channel isolation transformer T1, which can convert the +28V control power supply into four isolated power supplies (each of which includes +18V, -5V and GND zero potential), providing isolated power and GND zero potential for the six-way SiC MOSFET drive circuit. The six-way SiC MOSFET drive circuit uses an isolated drive chip and peripheral circuits to convert the PWM control signal input by the motor control unit into an isolated drive signal, thereby driving the SiC MOSFET. The SiC MOSFET three-phase full-bridge power module is used to drive a three-phase brushless DC motor.

[0078] The technical parameters of the SiC three-phase bridge drive circuit module product in 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 pins of the SiC three-phase bridge drive circuit module of this embodiment are 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, 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 ), the +12V power supply (VCC12V) output by it provides power input for the PWM controller in the four-channel isolated power supply, and the +5V power supply (VCC5V) output by it provides power input for the six-way 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, namely, 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 supply and GND zero potential for six SiCMOSFET drive circuits; The six-way SiC MOSFET drive circuit is used to convert the U-phase high-side control signal (IN+_UH), U-phase low-side control signal (IN+_UL), V-phase high-side control signal (IN+_VH), V-phase low-side control signal (IN+_VL), W-phase high-side control signal (IN+_WH), and W-phase low-side control signal (IN+_WL), a total of six PWM control signals output by the motor control unit, into a U-phase high-side isolated drive signal (PWM_UH), a U-phase low-side isolated drive signal (PWM_UL), a V-phase high-side isolated drive signal (PWM_VH), a V-phase low-side isolated drive signal (IN+_VL), and a 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 respectively 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), 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 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; The SiC MOSFET three-phase full-bridge power module is also 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. A 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 the two ends of the primary coil of the isolation transformer (T1), the source of the second MOS tube (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 with the same name; 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 a first parallel branch of the first diode (D1), a ninth resistor (R9) is connected in parallel on a second parallel branch, an eighth capacitor (C8) and a fifteenth capacitor (C15) are connected in series on a third parallel branch, a seventh resistor (R7) and a third voltage stabilizing diode (D3) are connected in series on a fourth parallel branch, 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 cathode of the third voltage stabilizing diode (D3) as a zero potential (GND-PHU) of a U-phase high-side isolation power supply, a cathode of the first diode (D1) serves as a +18V output terminal (18V-PHU) of a U-phase high-side isolation power supply, and a cathode of the third voltage stabilizing diode (D3) serves as a -5V output terminal (-5V-PHU) of a U-phase high-side isolation power supply; The second secondary coil of the isolation transformer (T1) is connected in series with a sixth diode (D6), the first parallel branch of the sixth diode (D6) is connected in parallel with a seventeenth capacitor (C17), the second parallel branch is connected in parallel with a fourteenth resistor (R14), the third parallel branch is connected in series with a sixteenth capacitor (C16) and a nineteenth capacitor (C19), the fourth parallel branch is connected in series with a thirteenth resistor (R13) and a tenth voltage stabilizing diode (D10), the sixteenth capacitor 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 cathode of the tenth voltage zener diode (D10) as the V-phase high-side isolated power supply zero potential (GND-PHV), the cathode of the sixth diode (D6) serves as the V-phase high-side isolated power supply +18V output end (18V-PHV), and the anode of the tenth voltage zener diode (D10) serves as the V-phase high-side isolated power supply -5V output end (-5V-PHV); The third secondary coil of the isolation transformer (T1) is connected in series with an eleventh diode (D11), the first parallel branch of the eleventh diode (D11) is connected in parallel with a twenty-ninth capacitor (C29), the second parallel branch is connected in parallel with a thirty-third resistor (R33), the third parallel branch is connected in series with a twenty-fifth capacitor (C25) and a thirty-fifth capacitor (C35), the fourth parallel branch is connected in series with a twenty-ninth resistor (R29) and a thirteenth voltage-stabilizing diode (D13), 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 coil of the isolation transformer (T1) is connected in series with a fourteenth diode (D14), the first parallel branch of the fourteenth diode (D14) is connected in parallel with a thirty-ninth capacitor (C39), the second parallel branch is connected in parallel with a forty-eighth resistor (R48), the third parallel branch is connected in series with a thirty-eighth capacitor (C38) and a forty-first capacitor (C41), and the fourth parallel branch 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) through 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: 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) through 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 housing (3), a lower substrate (4), and an upper substrate (5), wherein: The metal heat sink (1) is fixedly connected to the bottom of the insulating shell (3), the metal cover (2) is fixedly connected to the top of the insulating shell (3), the metal heat sink (1), the metal cover (2) and the insulating shell (3) on the side together enclose a module cavity, and a lower substrate (4) and an upper substrate (5) are arranged inside the module cavity, wherein the lower substrate (4) is welded to the metal heat sink (1) by eutectic welding, and the edge of the upper substrate (5) is fixedly mounted on a 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, the four-channel isolated power supply, and the six-way SiC MOSFET drive circuit are arranged on an upper substrate (5); The circuit between the lower substrate (4) and the upper substrate (5) is electrically connected via the 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 inner cavity of the module, the bottom of the support column (8) is fixed on the lower substrate (4), 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).

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 sink (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 by eutectic welding, and the remaining active chips are adhered to the upper PCB substrate by 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 by a 500 μm aluminum wire wedge, and the gate is bonded by a 150 μm aluminum wire wedge.

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