A new load frequency control approach in an isolated small power systems using coefficient diagram method

• Coefficient diagram method is applied for frequency control in an isolated islands.
• An isolated power system powered by diesel generator and renewable power source.
• Proposed Method is used the heat pump and electric vehicle to control the frequency.
• Proposed scheme was tested under random loads disturbances and photo-voltaic power.
• Proposed controller succeeded to reduce the effect of system disturbances.

This paper applies the Coefficient Diagram Method (CDM) as a new robust controller design of heat pump (HP) and plug-in hybrid electric vehicle (EV) for frequency control in an isolated small power system powered by diesel generator and renewable photovoltaic PV power source. In order to reduce frequency fluctuation resulted from the fluctuating power generation from renewable energy sources, the smart control of power consumption of HP and the power discharging of EV in the customer side can be performed.The CDM technique has been designed to enhance the performance and robustness against system uncertainties. Simulation studies confirm the superior robustness and frequency control effect of the proposed HP and EV controllers in comparison to other conventional controllers of HPs and EVs like the conventional PID controllers optimized using practical swarm controllers based a specified-structure mixed H2/H∞ control design.