A Sliding Mode Control-Based Master-Slave Power Sharing Method for an Islanded Microgrid Considering Voltage Harmonic Improvement

The proliferation of inverter-based distributed generation (DG) improves the grid features in a variety of aspects. Accordingly, this paper presents a control strategy that provides power-sharing among the different inverter-based DG units; Furthermore, the improvement of the voltage harmonic content of an inverter-based islanded microgrid can be obtained. In this proposed control scheme, sliding mode control is developed in master-slave control scheme and is applied to each inverter as switching method. Two methods of implementation of the control approach are proposed in this paper The first is based on the parallel operation of inverters extended to MG. In the second proposed method, the transmitted reference current only includes the output of voltage loop control of the master unit; furthermore, the received reference current of each slave DG unit is added to its output current. Therefore, the output currents of units are related to the loading and grid configuration. Simulation study implemented in MATLAB/Simulink software shows that the performance of both methods is acceptable in different scenarios while the second method leads to more voltage harmonic enhancement in presence of non-linear loads.

کلیدواژه ها:

master-slave control strategy ، harmonic distortion ، inverter based microgrid ، sliding mode control