Design, Modeling and Study of Inverter Integrated Reactive Power Compensation for Isolated Rural Microgrid

Diesel/Biogas generators are generally accompanied with renewable based isolated system due to the sporadic nature of renewable resources. One of the main difficulties associated with small sized isolated rural system is voltage fluctuation due to small disturbances. The rural load mainly comprises of household lighting, agriculture pumps & equipment and small commercial/industrial blocks. The voltage fluctuation affects the performance as well as the life of the electrical equipment. In this paper an isolated rural microgrid is considered with renewable energy sources being supported by diesel generator. The renewable energy resources are hydro with induction generator and Photo Voltaic System. The system is modeled such that inverter associated with Photo Voltaic System provides reactive power compensation apart from the diesel genset. Accordingly, DC Link capacitor and Inductor associated with PV Inverter are designed. The objective of the system study is to deliver uninterrupted and reliable power supply by maintaining regulation of the voltage. The results are verified with step change in load and step change in input solar power to study the dynamic performance of the system. The modeling has been carried out in Simulink.