Design of a High-Power Power Electronics Building Block Based on SiC MOSFET Modules

Power electronics building block (PEBB) is a new structure of power electronic equipment based on the concept of standardization. In this paper, a general design method for a high-power PEBB rated for 57.6kW, 1.2kV DC-link is given. The designed PEBB uses 1.7kV SiC MOSFET modules as power devices. The selection of DC-link capacitors is introduced in this paper. The design method of an air-cooled cooling system that contains an aluminum radiator and four DC fans is given. To verify the performance of the cooling system, COMSOL is used to simulate the SiC modules' temperature under full-power operation. The design schemes of the DC bus-bar and AC ports are also presented. The bus-bar uses a copper-based multilayer laminated bus-bar so that the SiC modules can be connected to the DC-link capacitors in the low-inductance loops. The thermal performance and mechanical strength of the bus-bar are simulated by COMSOL, and the parasitic parameters of it are simulated by Ansys Q3D. In addition, the detection and control methods used in the PEBB are also mentioned. The structure of the PEBB is completed by the integrated layout design. Finally, a 57.6 kW PEBB prototype is built. A pump-back test platform whose topology is a dual active bridge is built through two PEBBs. The experiment shows the temperature rise of SiC modules is low, and the maximum drain-source voltage of the SiC MOSFET is 1244V. The PEBB operates stably and reliably at 56.7kW, and the power density is up to 1920kW/m3.