EE shape low loss three-phase AC filter inductor design for three-phase PWM inverter

摘要

This paper proposes a three-phase AC filter inductor, which uses two soft magnetic materials, for use in three-phase pulse-width modulated (PWM) inverters. This inductor features loss reduction, achieves the same volume as conventional inductors, and has good inductance balance in each phase. First, a three-phase inductor that provides the same value of inductance in each phase is designed. Then, the inductor losses in a three-phase AC filter inductor used in a 1 kVA three-phase PWM inverter are evaluated through simulations and experiments. The conversion efficiency simulations illustrate that the proposed inductor improves the conversion efficiency. The conversion efficiencies of actual three-phase 1 kVA PWM inverters are measured, for the conventional and proposed AC filter inductors. In the experiments, the conversion efficiency in the case using the proposed inductor is found to be improved by approximately 1% at low power loads, when compared to the conventional inductors.