Transient Pulse Based Impedance Characterization of DC Link Capacitor for EV Systems

In this study, a method for impedance characterisation of DC-link capacitors based on transient pulse analysis is proposed. The fundamentals of the concept are presented and design considerations are discussed. The functionality of the proposed approach is supported by SPICE simulation with two different commercial capacitors from different manufacturers and validated with experimental results. Experimental results for equivalent series resistance, equivalent series inductance (ESL) and capacitance estimation are presented for commercial DC-link capacitors and compared with component analyser results. The simulation and experimental results show that the proposed method is a promising candidate for capacitance and ESL estimation of capacitors in EV traction systems.