This paper proposes a new controller design of heat pumps (HP) and plug-in hybrid electric vehicles (PHEV) for robust frequency control in a smart microgrid (MG) system with wind farm. The system frequency can be controlled by the smart power charging of HP and PHEV. The structure of power charge controller is a proportional integral derivative (PID) with single input. System uncertainties are modeled by the multiplicative uncertainty. By taking the robust stability margin into account, the particle swarm optimization (PSO) is applied to optimize the PID controller parameters of HP and PHEV concurrently based on specified-structure mixed H<inf>2</inf>/H<inf>∞</inf> control approach. Simulation results confirm the superior robustness and performance of the proposed control.
