Frequency Control Method by Delta Control of Renewable Energy Sources in Island Microgrid

摘要

Frequency regulation is of prime importance to keep supply and demand balance in power systems. In particular, in the case of microgrids with renewable energy sources such as photovoltaic or wind turbine, it becomes more challenging issue compared with bulk power systems due to its small moment of inertia. For the purpose of proper frequency regulation, it is proposed in this study to apply advanced controls of renewable energy sources to primary and secondary controls. Specifically, it was developed that the combinational application of inertial response and delta control for wind turbine, and active power curtailment for photovoltaic. The effectiveness of the proposed method was examined by using microgrid model consisting of conventional generators, loads, and renewable energy sources. The simulation results indicated the cooperative operation between three controls works properly and it was possible to keep frequency fluctuation within a reasonable range.