Power Management and Control Strategy of Hybrid Renewable Energy Sources in Islanded Microgrid

This paper presents a new power management and control strategy of a hybrid energy system including photovoltaic, fuel cell, battery and supercapacitor in a islanded microgrid, which provides both active and reactive power to support an local load. The photovoltaic unit is the primary energy resource, which to supply the maximum power produced to the load, utilization of maximum power point tracking (MPPT) technique. Battery and supercapacitor both are considered for their different power density to supply transient and steady load, respectively. To increase the reliability of the system, the fuel cell has been selected to keep the battery fully charged. All resources are connected to dc bus by different dc-dc converters, and then the hybrid system through voltage source inverter (VSI) connected to ac load. For managing the active and reactive power independently in hybrid system, the fuzzy-adaptive control scheme based on sliding mode control (SMC) with fractional-order has been presented. The fuzzy-adaptive part is applied to approximate both the equivalent and switching control term in the sliding mode controller.