Intelligent power module based on SIC SBD and having phase current acquisition function

Abstract

The invention discloses an intelligent power module based on an SIC SBD and having a phase current acquisition function, and belongs to the technical field of intelligent power module design. The intelligent power module comprises an IGBT chip, an SIC SBD chip, a resistor, a capacitor and an isolation digital amplifier. According to the invention, by adopting the SIC SBD chip, the reverse recovery current and the reverse recovery current time can be reduced, the turn-on speed can be improved, and the reverse recovery loss and the turn-on and turn-off loss can be reduced; the current sensor is integrated to the DBC substrate, and the sampling resistors connected in series are adopted to realize the isolation acquisition of the phase current, so that the problem of serious heating caused by the traditional integration to a PCB (Printed Circuit Board) is solved.

Description

Technical Field

[0001] This invention relates to an intelligent power module based on SiC SBD and with built-in phase current acquisition function, belonging to the field of intelligent power module design technology. Background Technology

[0002] Traditional intelligent power modules based on the IGBT+FRD model have two main problems. First, traditional FRDs suffer from high switching losses and high reverse recovery charge, making them prone to high-temperature damage in high-frequency, high-temperature environments. FRDs exhibit a significant reverse recovery process, with Qrr occurring in every switching cycle. This reverse recovery process increases the IGBT's turn-on and turn-off losses, and under high-voltage, light-load conditions, the FRD's switching losses account for a large proportion of the overall losses (approximately 50% of the total losses at a bus voltage of 300V and 10% of rated current). Second, they lack the capability for phase current detection output. This typically requires an external Hall sensor or a sampling resistor or chip on the PCB. Hall sensors increase the overall product size, while adding a sampling resistor to the PCB results in significant heat generation due to the high thermal resistance of the PCB and the lack of a heat dissipation path. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a new type of intelligent power module based on SiC SBD and with built-in phase current acquisition function, which reduces the reverse recovery loss and switching loss of the intelligent power module, improves the integration and reduces the size.

[0004] The technical solution of this invention is:

[0005] A smart power module based on SiC SBD and with built-in phase current acquisition function includes IGBT chips Q1 to Q6, SiC SBD chips D1 to D6, resistors R1 to R6, capacitors C1 and C6, and isolation digital amplifiers U1 to U2.

[0006] The IGBT chips Q1 to Q6 are connected in parallel with each of the SiC SBD chips D1 to D6; IGBT chips Q1 and Q4 are connected in series, IGBT chips Q2 and Q5 are connected in series, and IGBT chips Q3 and Q6 are connected in series.

[0007] The collectors of IGBT chips Q1, Q2, and Q3, and the negative terminals of SiC SBD chips D1, D2, and D3 are all connected to the P-stage input; the emitters of IGBT chips Q4, Q5, and Q6, and the positive terminals of SiC SBD chips D4, D5, and D6 are all connected to the N-stage input.

[0008] The emitter output terminal of the IGBT chip Q1 serves as the U-phase output terminal, the emitter of the IGBT chip Q2 is connected to resistor R1 and serves as the V-phase output terminal, and the emitter of the IGBT chip Q3 is connected to resistor R2 and serves as the W-phase output terminal.

[0009] One end of resistor R3 is connected to the V-phase output terminal, and the other end of resistor R3 is connected to one end of capacitor C1 and the AINP pin of isolation digital amplifier U1; one end of resistor R4 is connected to the emitter of IGBT chip Q2, and the other end of resistor R4 is connected to the AINN pin of isolation digital amplifier U1 and the other end of capacitor C1.

[0010] One end of resistor R5 is connected to the W-phase output terminal, and the other end of resistor R5 is connected to one end of capacitor C6 and the AINP pin of isolation digital amplifier U2; one end of resistor R6 is connected to the emitter of IGBT chip Q3, and the other end of resistor R6 is connected to the AINN pin of isolation digital amplifier U2 and the other end of capacitor C6.

[0011] Furthermore, the P-pole, N-pole, U-phase output terminal, V-phase output terminal, and W-phase output terminal are all interfaces between the intelligent power module and external circuits; among them, the P-pole and N-pole are the positive and ground of the power input; the U-phase output terminal, V-phase output terminal, and W-phase output terminal are the three terminals of the three-phase motor.

[0012] Furthermore, resistors R1 and R2 are sampling resistors, and the phase current values ​​of phase V and phase W are acquired through the outputs of isolation digital amplifiers U1 and U2. Specifically, the voltage V1 across resistor R1 is acquired through isolation digital amplifier U1, and the current value of phase V is calculated. The voltage V2 across resistor R2 is acquired through isolation digital amplifier U2, and the current value of phase W is calculated.

[0013] Furthermore, the isolation digital amplifiers U1 to U2 are model AMC1303M.

[0014] Furthermore, IGBT chips Q1-Q6, SiC SBD chips D1-D6, and resistors R1-R2 are all mounted on the DBC substrate. Resistors R1-R2 are sampling resistors and are mounted on the DBC substrate at the positions of the V-phase output terminal and the W-phase output terminal.

[0015] Furthermore, resistors R3 and R4 and capacitor C1 form one set of RC filters, and resistors R5, R6 and capacitor C6 form another set of RC filters. The filter parameters are adjusted according to the phase current frequency that needs to be tested.

[0016] Furthermore, the AVDD pin of the isolated digital amplifier U1 is connected to AVDD1, the AGND pin is connected to AGND1, the DOUT pin is connected to DOUT1, the CLKOUT pin is connected to CLK1, the DGND pin is connected to GND, and the DVDD pin is connected to VDD; wherein, CLK1 is the output clock signal; DOUT1 is the output digital signal; VDD is the positive power supply, and GND is the power supply ground.

[0017] Furthermore, the isolated digital amplifier U1 is also provided with capacitors C2 and C3, both of which are filter capacitors; the DGND pin of the isolated digital amplifier U1 is connected to one end of capacitor C2 and one end of capacitor C3 in parallel and connected to GND, and the DVDD pin is connected to the other end of capacitor C2 and the other end of capacitor C3 in parallel and connected to VDD.

[0018] Furthermore, the AVDD pin of the isolated digital amplifier U2 is connected to AVDD2, the AGND pin is connected to AGND2, the DOUT pin is connected to DOUT2, the CLKOUT pin is connected to CLK2, the DGND pin is connected to GND, and the DVDD pin is connected to VDD; wherein, CLK2 is the output clock signal; DOUT2 is the output digital signal; VDD is the positive power supply, and GND is the power supply ground.

[0019] Furthermore, the isolated digital amplifier U2 is also provided with capacitors C4 and C5, both of which are filter capacitors; the DGND pin of the isolated digital amplifier U2 is connected to one end of capacitor C4 and one end of capacitor C5 in parallel and connected to GND, and the DVDD pin is connected to the other end of capacitor C4 and the other end of capacitor C5 in parallel and connected to VDD.

[0020] The advantages of this invention compared to the prior art are:

[0021] (1) By introducing SiC SBD into IPM, this invention reduces reverse recovery current and reverse recovery time, increases turn-on speed, and reduces reverse recovery loss and turn-on / turn-off loss compared to traditional smart power modules that use silicon-based FRD.

[0022] (2) The present invention integrates a current sensor onto the DBC substrate and achieves isolated acquisition of phase current through a series sampling resistor, which solves the problem of severe heat generation caused by traditional integration onto the PCB. Heat dissipation through the DBC substrate can reduce the heat of the sampling resistor and prevent problems such as solder joint melting caused by excessive temperature. Attached Figure Description

[0023] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0024] Figure 1 This is a schematic diagram of the intelligent power module circuit according to an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the DBC substrate according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the 750V250A intelligent IGBT chip according to an embodiment of the present invention. Detailed Implementation

[0027] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0028] This invention proposes an intelligent power module based on SiC SBD and with built-in phase current acquisition function, such as... Figure 1 As shown, the system includes IGBT chips Q1-Q6, SiC SBD chips D1-D6, resistors R1-R6, capacitors C1-C5, and isolation digital amplifiers U1-U2. The isolation digital amplifiers U1-U2 are model AMC1303M.

[0029] The collectors of IGBT chips Q1 to Q6 are connected to the negative terminals of D1 to D6, respectively, and the emitters of Q1 to Q6 are connected to the positive terminals of D1 to D6, respectively.

[0030] IGBT chip Q1 and SiC SBD chip D1 are connected in parallel, and IGBT chip Q4 and SiC SBD chip D4 are connected in parallel. IGBT chips Q1 and Q4 are connected in series, and the output is a U-phase output when connected in series. The collector of IGBT chip Q1 is connected to the P-stage input, and the emitter of Q4 is connected to the N-stage input.

[0031] IGBT chip Q2 and SiC SBD chip D2 are connected in parallel, and IGBT chip Q5 and SiC SBD chip D5 are also connected in parallel. IGBT chips Q2 and Q5 are connected in series. The emitter of IGBT chip Q2 is connected to one end of resistor R1, and the other end of resistor R1 serves as the V-phase output. The collector of IGBT chip Q2 is connected to the P-stage input, and the emitter of Q5 is connected to the N-stage input.

[0032] IGBT chip Q3 and SiC SBD chip D3 are connected in parallel, and IGBT chip Q6 and SiC SBD chip D6 are also connected in parallel. IGBT chips Q3 and Q6 are connected in series. The emitter of IGBT chip Q3 is connected to one end of resistor R2, and the other end of resistor R2 is the W-phase output. The collector of IGBT chip Q3 is connected to the P-stage input, and the emitter of IGBT chip Q6 is connected to the N-stage input.

[0033] One end of resistor R3 is connected to resistor R1 as one end of the V-phase output, and the other end of resistor R3 is connected to one end of capacitor C1 and pin 2 of isolation digital amplifier U1. One end of resistor R4 is connected to the emitter of IGBT chip Q2, and the other end of resistor R4 is connected to pin 3 of U1 and the other end of capacitor C1.

[0034] Pin 1 of the isolated digital amplifier U1 is connected to AVDD1, pin 4 is connected to AGND1, pin 6 is connected to DOUT1, pin 7 is connected to CLK1, pin 5 is connected to one end of capacitor C2 and one end of capacitor C3 and connected in parallel to GND, and pin 8 is connected to the other end of capacitor C2 and the other end of capacitor C3 and connected in parallel to VDD.

[0035] One end of resistor R5 is connected to resistor R2 as one end of the W-phase output, and the other end of resistor R5 is connected to one end of capacitor C6 and pin 2 of isolation digital amplifier U2. One end of resistor R6 is connected to the emitter of IGBT chip Q3, and the other end of resistor R6 is connected to pin 3 of isolation digital amplifier U2 and the other end of capacitor C6.

[0036] The isolation digital amplifier U2 has pin 1 connected to AVDD2, pin 4 connected to AGND2, pin 6 connected to DOUT2, pin 7 connected to CLK2, pin 5 connected to one end of capacitor C4 and one end of capacitor C5 and connected to GND, and pin 8 connected to the other end of capacitor C4 and the other end of capacitor C5 and connected to VDD.

[0037] The terminals P, N, U, V, W, CLK1, DOUT1, CLK2, DOUT2, AVDD1, AGND1, AVDD2, AGND2, VDD, and GND are the interfaces between this invention and external circuits. P and N are the positive and ground terminals for power input, respectively; U, V, and W are the three terminals of the three-phase motor; CLK1 and CLK2 are the output clock signals; DOUT1 and DOUT2 are the digital signal output ports; VDD is the positive power supply for the AMC1303M control terminal; and GND is the ground power supply for the control terminal. For specific requirements of CLK, DOUT, and VDD, please refer to the AMC1303M user manual. AVDD1 and AGND1 are the power supply and ground for the U1 detection terminal, and AVDD2 and AGND2 are the power supply and ground for the U2 detection terminal.

[0038] Resistors R3-R6 are 1000 ohms, capacitors C1 and C6 are 100pF and 100pF respectively. Resistors R3, R4, and C1, and resistors R5, R6, and C6 respectively form two RC filters. The filter parameters can be adjusted according to the phase current frequency to be tested. Capacitors C2 (0.1uF), C3 (2.2uF), C4 (0.1uF), and C5 (2.2uF) are the filter capacitors for the AMC1303M power supply. Resistor R2 is 0.3 milliohms, and resistor R1 is 0.3 milliohms. The values ​​of resistors R1 and R2 are calculated based on the sampling current. The rated current of this product is 250A, the voltage at the rated current is ±75mV, and the heat generation is 19W. At twice the rated current, the voltage is ±150mV, and the heat generation is 38W. This meets the input range requirement of ±250mV of AMC1303M. The selection of sampling resistors mainly considers the heat generation and the voltage across the sampling resistor terminals.

[0039] IGBT chips Q1-Q6, SiC SBD chips D1-D6, and resistors R1-R2 are mounted on the DBC substrate, such as Figure 2 The resistors R2 and R1 are sampling resistors. The positions of R2 and R1 on the DBC correspond to the current output positions of phases V and W. By integrating sampling resistors R1 and R2 at the output terminals of phases V and W, the phase current values ​​of phases V and W are acquired through isolated digital amplifiers U1 and U2. Specifically, isolated digital amplifier U1 acquires the voltage V1 across resistor R1 (leading out through pins 1 and 2), and calculates the current value of phase V using the formula I1 = V1 / R1. Isolated digital amplifier U2 acquires the voltage V2 across resistor R2 (leading out through pins 3 and 4), and calculates the current value of phase W using the formula I2 = V2 / R2. This invention eliminates the need for a bulky external Hall current sensor, improving system integration and reducing costs. By using a SiC SBD instead of a traditional FRD, the overall switching losses of the system are reduced by approximately 30%, achieving the goals of reducing heat generation and EMI interference.

[0040] In this invention, Q1 to Q6 can also be IGBT chips with sensors, including current and temperature sensors. They can output the chip's current and junction temperature, and can work with the drive circuit to provide overcurrent and overtemperature protection, possessing the ability to intelligently protect themselves from damage. For example... Figure 3 As shown, the chip has lead-out electrodes such as a temperature sensor cathode, a temperature sensor anode, a gate, an emitter, and a current sensor. These electrodes are respectively connected via... Figure 2 Each pin in the circuit is led out to a pin on the housing, and finally to the control printed circuit board.

[0041] The embodiments described above are merely preferred embodiments of the present invention. Ordinary variations and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A smart power module based on SiC SBD and with built-in phase current acquisition function, characterized in that, This includes IGBT chips Q1-Q6, SiC SBD chips D1-D6, resistors R1-R6, capacitors C1 and C6, and isolation digital amplifiers U1-U2; The IGBT chips Q1 to Q6 are connected in parallel with each of the SiC SBD chips D1 to D6; IGBT chips Q1 and Q4 are connected in series, IGBT chips Q2 and Q5 are connected in series, and IGBT chips Q3 and Q6 are connected in series. The collectors of IGBT chips Q1, Q2, and Q3, and the negative terminals of SiC SBD chips D1, D2, and D3 are all connected to the P-stage input; the emitters of IGBT chips Q4, Q5, and Q6, and the positive terminals of SiC SBD chips D4, D5, and D6 are all connected to the N-stage input. The emitter output terminal of the IGBT chip Q1 serves as the U-phase output terminal, the emitter of the IGBT chip Q2 is connected to resistor R1 and serves as the V-phase output terminal, and the emitter of the IGBT chip Q3 is connected to resistor R2 and serves as the W-phase output terminal. One end of resistor R3 is connected to the V-phase output terminal, and the other end of resistor R3 is connected to one end of capacitor C1 and the AINP pin of isolation digital amplifier U1; one end of resistor R4 is connected to the emitter of IGBT chip Q2, and the other end of resistor R4 is connected to the AINN pin of isolation digital amplifier U1 and the other end of capacitor C1. One end of resistor R5 is connected to the W-phase output terminal, and the other end of resistor R5 is connected to one end of capacitor C6 and the AINP pin of isolation digital amplifier U2; one end of resistor R6 is connected to the emitter of IGBT chip Q3, and the other end of resistor R6 is connected to the AINN pin of isolation digital amplifier U2 and the other end of capacitor C6.

2. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, The P-phase, N-phase, U-phase, V-phase, and W-phase output terminals are all interfaces between the intelligent power module and external circuits. Among them, the P-phase and N-phase are the positive and ground of the power input, respectively; the U-phase, V-phase, and W-phase output terminals are the three terminals of the three-phase motor.

3. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, Resistors R1 and R2 are sampling resistors. The phase current values ​​of phase V and phase W are collected through the output of isolation digital amplifiers U1 and U2. Specifically, the voltage V1 across resistor R1 is collected by isolation digital amplifier U1 to calculate the current value of phase V; the voltage V2 across resistor R2 is collected by isolation digital amplifier U2 to calculate the current value of phase W.

4. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, The isolation digital amplifiers U1 and U2 are model AMC1303M.

5. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, IGBT chips Q1-Q6, SiC SBD chips D1-D6, and resistors R1-R2 are all mounted on the DBC substrate. Resistors R1-R2 are sampling resistors and are mounted on the DBC substrate at the positions of the V-phase output terminal and the W-phase output terminal.

6. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, Resistor R3, resistor R4 and capacitor C1 form one set of RC filters, and resistor R5, resistor R6 and capacitor C6 form another set of RC filters. The filter parameters are adjusted according to the phase current frequency to be tested.

7. The intelligent power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, The isolated digital amplifier U1 has its AVDD pin connected to AVDD1, AGND pin connected to AGND1, DOUT pin connected to DOUT1, CLKOUT pin connected to CLK1, DGND pin connected to GND, and DVDD pin connected to VDD; where CLK1 is the output clock signal; DOUT1 is the output digital signal; VDD is the positive power supply, and GND is the power supply ground.

8. A smart power module based on SiC SBD and with built-in phase current acquisition function according to claim 7, characterized in that, The isolated digital amplifier U1 is also equipped with capacitors C2 and C3, both of which are filter capacitors; the DGND pin of the isolated digital amplifier U1 is connected to one end of capacitor C2 and one end of capacitor C3 in parallel and connected to GND, and the DVDD pin is connected to the other end of capacitor C2 and the other end of capacitor C3 in parallel and connected to VDD.

9. A smart power module based on SiC SBD and with built-in phase current acquisition function according to claim 1, characterized in that, The isolated digital amplifier U2 has its AVDD pin connected to AVDD2, AGND pin connected to AGND2, DOUT pin connected to DOUT2, CLKOUT pin connected to CLK2, DGND pin connected to GND, and DVDD pin connected to VDD; where CLK2 is the output clock signal; DOUT2 is the output digital signal; VDD is the positive power supply, and GND is the power supply ground.

10. A smart power module based on SiC SBD and with built-in phase current acquisition function according to claim 9, characterized in that, The isolated digital amplifier U2 is also equipped with capacitors C4 and C5, both of which are filter capacitors; the DGND pin of the isolated digital amplifier U2 is connected to one end of capacitor C4 and one end of capacitor C5 in parallel and connected to GND, and the DVDD pin is connected to the other end of capacitor C4 and the other end of capacitor C5 in parallel and connected to VDD.

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