An Area Equalization Modulation Strategy for Multilevel Converter Used in Large-Scale Battery Energy Storage Application

In this paper, a fundamental switched area equalization modulation strategy (AEMS) is presented for a multilevel converter (MLC) used in large-scale battery-energy storage (BES) system. In this AEMS, the switching angles are computed online by equalizing the area under the reference voltage signal and carrier signal. In this BES system, the AEMS provides simple and reasonably good voltage harmonics performance for MLC. MATLAB/Simulink model of a 13-level cascaded H-bridge (13-level CHB) with storage is developed and implemented in real-time using OPAL-RT to validate the concept. Various performance results under steady-state and dynamic conditions are obtained and presented in detail.