Energy management and control systems for hybrid wind-solar energy system with battery storage

Abstract

A hybrid wind solar energy system with battery storage and its control systems are presented in this dissertation. The proposed system consists of a wind turbine, a solar panel, a battery storage unit and a set of loads. A power electronics interface, based on various converters, is used to integrate the renewable energy sources and the storage device to the main DC-bus feeding a single phase AC load. The main challenge of the hybrid system is to maintain the load demand under constraints. The objective of the proposed controllers is to ensure a proper control and coordination between all the sources of the system. At the wind energy side, a speed controller is used to keep the rotor speed under control for safe operation of the wind turbine. At the solar energy side, an incremental conductance method approach is realized to extract the maximum power from solar irradiance. A bidirectional DC-DC converter is employed to control the charging and discharging of the battery storage system. An energy management system is developed to keep a balanced energy in the hybrid system. A load voltage regulator enables the system to fix the output voltage and frequency. An experimental setup of the hybrid energy system is developed using electrical devices from Festo (formerly LabVolt) and rapid control prototyping is achieved using the real-time OPAL-RT digital control system. Experimental results for various conditions are presented to validate the control algorithms developed in this work.