Optimized DC-AC EMI Filter Design for DC-Fed High Speed SiC-Based Motor Drive

This paper presents a consolidated design procedure for AC and DC electromagnetic interference (EMI) filter of a high altitude high current based motor drive. A decoupled design method using damping of motor side propagation impedance and integrated CM-DM filter is proposed to achieve high specific power target. Simplified CM and DM models for a three-level inverter are used for the overall design and validation. Consequently, the form factor optimization of such a structure is discussed. The impact of high altitude from partial discharge and high thermal impedance effects are incorporated in the design. A high filter specific power of approximately 66.66 kW/kg is achieved under high altitude and high ambient temperature. A 211-kW, 300 A rated three level T-type inverter prototype is built to validate the filter design for conducted EMI noise mitigation.