Coordination of Inverter-Based Distributed Generation Units and Reactive Power Compensators in Power Systems

Abstract

High penetration of wind turbines and photovoltaic arrays in distribution system can result in overvoltages and voltage variation. However, with help of their converters, voltage and reactive power control of these distributed generation units (DG) is possible. Reactive power capability of wind turbines and photovoltaic systems are explained in this paper and a decentralized control method is used to control the voltage of the units. Furthermore, coordination of DGs and the reactive power compensators is considered to avoid power losses and voltage fluctuation. IEEE 33 bus distribution network is considered as test system and simulations are performed. The results show that the voltage profile is improved with reactive power support of DGs and proposed method is successful in voltage control of the system. Nomenclature= maximum allowed converter current = maximum allowed rotor current = maximum allowed stator current = maximum allowed converter voltage P = active power of DG = active power of rotor = active power of stator = reactive power capability of DG = reactive power limit caused by converter current = reactive power limit caused by converter voltage s = slip = grid voltage at the point of common coupling X = total equivalent reactance = mutual reactance = stator leakage reactance