Dual Mode Power Sharing Control and Voltage Compensation for Islanded Microgrid

Numerous control techniques are being applied to control the parallel connected inverters. The well-known techniques among them are the communication and non-communication-based techniques. To avoid communication link, droop control technique is widely used in parallel connected inverter's based microgrids. Conventional droop control however in terms of power-frequency and reactive power-voltage do not attain desired outcomes for power sharing accuracy especially for reactive power sharing. Another problem in conventional droop control is the voltage deviations. This paper proposes a control technique which utilises the conventional and impedance power droop technique together. In this control technique impedance power droop control strategy is employed that individually has to deal with steady state conditions and conventional droop is used for start-up and transient states as a supplementary approach. Voltage deviation is totally removed as well as tracking errors at steady state are also decreased. Besides errors correction due to voltage deviation this technique does not need recognition of system parameters. Simulation results proves that proposed approach is very simple to implement with accurate power sharing capability.