A Battery Storage System for PMG-based WECSs

Conventional approaches to electric power generation has become concerning for the environment. As a result, several changes to power systems have been introduced. Among these changes, a significant number of distributed generation units (DGUs) are being integrated in power systems. For, DGUs strive to offset conventional generation by utilizing renewable energy sources. Largely, DGUs have trended towards the use of wind energy conversion systems (WECSs), where modern WECSs are favoring the variable speed PMG-based architectures. The relative novelty of these systems, however, has emphasized challenges that limit their applicability. Of these challenges, PMG torque pulsations, and PCC frequency have been regarded as the most troublesome. As of late, energy storage systems (ESSs) and new power electronic converter (PEC) topologies are being recommended to overcome these challenges. This work aims to develop and evaluate a split-bus PMG-based WECS architecture, that takes advantage of a generator charged and PCC discharged battery storage system (BSS) to support PCC frequency stability, as well as using a modified cascaded H-bridge (MCHB) generator-side PEC to reduce PMG-torque pulsations. The developed system is modeled in simulation and constructed in laboratory. Several operating conditions of wind speed, power command, and BSS charging are investigated.