all-SiC Power Module Research Articles

Research on Dual 12-Phase 12-Slot Winding Permanent-Magnet Propulsion System Based on All-SiC Power Module

All-SiC power modules have lately received great attention for multiphase motor propulsion systems due to their low radiator temperature and high efficiency. However, the application of all-SiC power modules for dual 12-phase 12-slot winding permanent-magnet propulsion systems remains an ongoing challenge, owing to synchronous operation. In an effort to overcome this challenge, this article quantified and compared the all-SiC power module with Si-insulated gate bipolar transistor (IGBT) to underpin the all-SiC power module as the preferred choice for propulsion inverter application. The motor mathematical model and control strategy were illustrated in detail. Moreover, the crucial features of the propulsion inverter and synchronous control were elucidated by the theoretical and experimental analysis. The synchronous switching of the dual all-SiC power modules allowed the same slot windings to achieve excellent operation. The experimental results were given for the operation of propulsion systems based on all-SiC power modules. The motor operations under different speeds were investigated as well. Finally, the fault tolerance of the dual 12-phase 12-slot permanent magnet synchronous motor (PMSM) was validated under an open circuit.

Si-IGBT and SiC-MOSFET hybrid switch-based 1.7 kV half-bridge power module

• Design guidelines, fabrication process, and evaluation of a 1.7-kV and 300-A multi-chip half bridge power module using the novel Si-IGBT and SiC-MOSFET hybrid switch in each switch position. • The module achieves its maximum DC current rating with a 6:1 current ratio of Si to SiC. • A novel custom-designed TPG-encapsulated metal base plate is proposed. • Silver clips for top-side interconnect in the module, facilitating a wire bond-less interconnection, high reliability, and low power loop inductance. • High thermal dissipation capability while maintaining a near-isolated thermal path for the SiC MOSFET to operate at a higher temperature than the Si-IGBT. This paper informs the design guidelines, fabrication process, and evaluation of a 1.7-kV and 300-A multi-chip half bridge power module using the novel Si-IGBT and SiC-MOSFET hybrid switch in each switch position. The module achieves its maximum DC current rating with a 6:1 current ratio of Si to SiC. This high current ratio yields significant cost savings compared to an all-SiC power module. The module employs high-reliability silver clips, which replaces conventional wire bonds for top-side interconnection, to partly enable a low power loop inductance of 12.38 nH. A novel thermal pyrolytic graphite-encapsulated metal baseplate is key to reducing the thermal coupling among the adjacent Si and SiC die, enabling higher junction temperature for SiC die relative to the Si die.

An Integrated SiC CMOS Gate Driver for Power Module Integration

With high-temperature power devices available, the support circuitry required for efficient operation, such as a gate driver, is needed as part of a complete high-temperature solution. The design of an integrated silicon carbide (SiC) gate driver using a 1.2-μm complementary metal–oxide–semiconductor (CMOS) process is presented. Adjustable drive strength is added to facilitate a minimal external component requirement for high-temperature power modules and lays the groundwork for dynamic adjustment of drive strength. The adjustable drive strength feature demonstrates a capability of reducing overshoot and controlling dv / dt dynamically. Measurement of the gate driver was performed driving a power mosfet gate over temperature, exceeding 500 °C. High-speed and high-voltage room temperature evaluation is provided, demonstrating a system capable of high performance over temperature. The driver accomplishes better than 75 ns of rise and fall time driving the Cree CPM3-0900-0065B from room temperature to over 500 °C indicating that it will be ideal for integration into an all-SiC power module where driver, protection circuits, and power devices are fabricated in SiC.

Interference source analysis and EMC design for All-SiC power module in EV charger

Silicon carbide (SiC) power devices suitable for high-frequency, high-power density and high-temperature applications, and thus gain a broad prospect in the electric vehicle (EV) charger area. However, the high-frequency switching of SiC devices under high-power application challenges the electromagnetic compatibility (EMC) of the power module. Noises generated from high-frequency switching need to be analyzed and suppressed. This paper introduces the configuration of a 30 kW All-SiC power module designed for EV charger, then reveals the interference source analysis. Based on the interference analysis, a double π electromagnetic interference (EMI) filter is added, intended for this All-SiC power module. Experimental results show that the All-SiC power module achieves excellent efficiency over a wide power range. Meanwhile, the conducted EMI measurement is reported to verify the effectiveness of EMC design.

Mission-Profile-Based Lifetime Prediction for a SiC mosfet Power Module Using a Multi-Step Condition-Mapping Simulation Strategy

The reliability analysis and lifetime prediction for SiC-based power modules is crucial in order to fulfill the design specifications for next-generation power converters. This paper presents a fast mission-profile-based simulation strategy for a commercial 1.2-kV all-SiC power module used in a photovoltaic inverter topology. The approach relies on a fast condition-mapping simulation structure and the detailed electro-thermal modeling of the module topology and devices. Both parasitic electrical elements and thermal impedance network are extracted from the finite-element analysis of the module geometry. The use of operating conditions mapping and look-up tables enables the simulation of very long timescales in only a few minutes, preserving at the same time the accuracy of circuit-based simulations. The accumulated damage related to thermo-mechanical stress on the module is determined analytically, and a simple consumed lifetime calculation is performed for two different mission profiles and compared in different operating conditions.

SiC-MOSFETを対象とした直流側寄生インダクタンスに起因するスイッチング損失の影響評価

Recently, high-speed switching circuits using SiC power devices have been developed for next-generation power electronics circuits and applied to actual traction systems in Japan. Stray inductances caused by DC capacitors, bus bars and power devices are one of the most critical parameters that influences over-voltage and switching loss. This paper presents an investigation into the influence of stray inductance on the switching performance of power devices. In particular, this paper focuses on the effects of stray inductance on both turn-on loss and turn-off loss, and can be estimated using the proposed impedance ratio method of the stray inductance. To verify the proposed procedure, experimental results are demonstrated using an all-SiC power module.

Design and Application of High-Voltage SiC JFET and Its Power Modules

This paper presents the structural design, prototype development, and testing of high-voltage silicon carbide (SiC) trenched-and-implanted vertical JFETs. Key design factors including drift layer doping concentration and thickness, channel dimensions, and termination structures are studied with numerical simulations. Devices are then fabricated in our research level facilities. The fabricated device has an active region of 4 mm2 and can conduct a current of 2.8 A at a drain voltage of 3 V and a gate bias of 2.9 V. With a negative gate bias of −5 V, the breakdown voltage is over 4500 V. Based on these devices, two modules are designed and developed. One is a 4500 V/50-A SiC JFET power module. The other one is an all-SiC power module with SiC JFETs and SiC JBS diodes. And the second one is also evaluated in a high-frequency boost converter. The testing results show that this All-SiC module is capable of working at a frequency up to 100 kHz with both turn-on and turn-off time less than 150 ns. A high converter efficiency of 97% is obtained at a 50-kHz switching frequency and the efficiency is 95% at a switching frequency of 100 kHz. This paper demonstrates that the SiC JFET and its power module can be used for SiC device applications in medium-voltage range.

250 °C-Operated sandwich-structured all-SiC power module

The operation of a sandwich structured all-SiC power module is demonstrated at 250 °C. The power module was designed by considering two thermal deformation issues. Thermally induced bending of the SiN-AMC substrates is reduced by introducing symmetrical Cu wiring patterns on both sides of the SiN ceramic plate. The concentration of stress located in the gate joint material is drastically reduced by introducing a trench structure in the Cu wiring layer of the gate interconnection. A double pulse test at a high temperature is carried out. At 250 °C, the all-SiC sandwich-structured power module was successfully operate at 600 V and 15 A. The maximum switching transient speed (dV/dt) of turn-on and turn-off are observed 10.7 and 12.1 V/ns, respectively.