Robust Control Strategies for SyRG-PV and Wind-Based Islanded Microgrid

The nonlinearity in the consumption does not maintain steady voltage or frequency; therefore, in this article, a circular limited cycle oscillator frequency locked loop with prefilter (CLO-FLL-WPF) based control for voltage source converter control is used to achieve voltage and frequency regulation in an islanded microgrid (MG). This control is implemented to compensate local load reactive power, harmonic currents, and load unbalance. Besides, the active power of local loads is shared among the multiple energy sources. The CLO-FLL-WPF control technique performance is validated experimentally and through simulations by comparing it with the existing control algorithm in a MG. This MG is a combination of the solar photovoltaic array, pico-hydro turbine-driven synchronous reluctance generator, permanent magnet brushless dc generator based wind energy conversion, and battery storage. In traditional battery control, a proportional-integral control approach is used, which can cause a stability problem. Thereby, in this article, the bidirectional dc–dc converter control method is used, which provides improved stability and makes the controller design straightforward. Test results validate the effectiveness of the control algorithm under different dynamic and steady-state conditions.