A Design Optimisation Tool for Maximising the Power Density of 3-Phase DC-AC Converters Using Silicon Carbide (SiC) Devices

The emergence of wide-bandgap devices, e.g. silicon carbide (SiC), has the potential to enable very high-density power converter design with high-switching frequency operation capability. A comprehensive design tool with a holistic design approach is critical to maximise the overall system power density,
e.g by identifying the optimal switching frequency. This paper presents a system level design tool that optimises the power density (volume or mass) of a 3-phase, 2-level DC-AC converter. The design tool optimises the selection of the devices, heatsink and passive components (including the design of the line, EMI
and DC-link filters) to maximise the power density. The structure of the optimisation algorithm has been organised to reduce the number of potential design combinations by over 99%, and thus produces fast simulation times. The design tool predicts that when SiC devices are used instead of Si ones, the power density is increased by 159.4%. A 5 kW, 600 V DC-link, 3-phase, 2-level DC-AC converter was experimentally evaluated in order to confirm the accuracy of the design tool.