Control Management Strategy of Stand-Alone Hybrid Power Micro-System Using Super-Capacitor

Abstract

This paper concerns the power management of an isolated hybrid micro-system for residential electricity supply, comprising a variable speed wind turbine (VSWT) and a photovoltaic (PV) panel as principal sources. A supercapacitor (SC) bank is considered as a storage system. These sources are connected to a three-phase load via a unidirectional inverter and an RLC filter. Taking into account the fluctuating nature of renewable sources and the variation of the required power, a diesel engine which is considered as a backup source and a dump load which is regarded as an auxiliary load, are connected on the AC side to ensure balance between the generated and the requested powers. In fact, a control strategy is developed to manage the power flows between the hybrid system devices and to make decision to choose the optimal operating mode ensuring the continuous supply of the load and maintaining the SC state of charge (SOC) at acceptable levels. Simulation results are presented to show the effectiveness of the proposed control system under six operating modes.