Simplified Power Loss Model for Aluminum Electrolytic Capacitors in Single-Phase Inverters

This letter proposes a simple yet practical power loss model of dc-link capacitors used in single-phase inverters. The low-frequency and high-frequency capacitor ripple current components make the existing power loss models either oversimplified by ignoring the high-frequency effects or overcomplicated with detailed analytical solutions. The proposed simplified model can achieve negligible errors with respect to the detailed model without the need of double fast Fourier transform. Different modulations and topologies are analyzed to show the applicability of the proposed method. A 2-kW single-phase inverter case study is presented to demonstrate the accuracy and ease of use of the proposed model.