Study on Energy Control Strategies in Microgrid-Modeling and Simulation

This paper sets up a simplified model of microgrid, which consist of wind power, PV, energy storage and loads. The distributed sources in the microgrid are controlled using different strategies: PV and wind power are controlled in PQ control mode; while energy storage controlled in PQ mode during grid- connected operation, and in droop control mode when the microgrid is switched to the islanding operation. It is proved by the simulations in Matlab/Simulink that it´s possible to achieve frequency and voltage stability of microgrid in situations such as cutting into the islanding mode, PV or wind output fluctuation, etc through load switching, generation power control of wind and PV, and adjustment of the output characteristic curve of energy storage. Also, the microgrid can be adjusted to be synchronized with the grid and seamless reconnected to the grid when it´s recovered. The simulation results demonstrate the feasibility and effectiveness of the proposed control strategies.