Optimal Control of a Standalone Wind-Solar-Battery Power System with a Quasi-Z-Source Inverter

This paper presents a battery-assisted quasi-Z-source inverter (qZSI) powered by a wind-solar hybrid generation system for autonomous load supply. The considered wind energy conversion system (WECS) utilizes a self-excited induction generator (SEIG) for electricity generation. Maximum power point tracking algorithms (MPPTs) are implemented to capture the maximum available power from both the WECS and the photovoltaic (PV) system. The batteries compensate for the oscillations in the available wind and solar power so as to ensure continuous operation of the system. In addition, the utilized qZSI, being a single-stage inverter with buck/boost capability, eliminates the requirement for an additional transformer or dc-dc boost converter. Such a hybrid generation system is for the first time proposed here. Its performance has been experimentally validated over a wide range of operating conditions by using a 5 kW experimental setup. The control algorithm was executed in real time by means of the DS1103 and MicroLabBox controller boards (dSpace).