A Model Predictive Control Scheme for Parallel-connected Inverter-based Distributed Generators in Micro-Grids

In recent, microgrids have been considered as an economic and efficient way to integrate distributed renewable resources on the community level. However, the current and power sharing between each distributed generations, especially under heavy power demands and casualty conditions, is still an important issue. This paper presents a model predictive control approach for parallel-connected inverter-based distributed generators in micro-grid system under islanded operation mode. The dynamic system model is developed and used to predict future system behaviors based on the candidate control input sequences and the current states. The desired cost function is build and by minimizing the cost function designed controller chooses the optimal control solution and applied as the current control input. The proposed control scheme provides automatic and fast regulation to ensure the resultant output voltage tracks the reference waveform and minimize the circulating current between parallel-connected inverters. Several simulation scenarios are presented to show the efficiency of the proposed controller using PLECS software.