Rate of Change of Frequency(RoCoF) Improvement of Low Inertia Power System by Using Refrigerated Warehouse

The frequency regulation is a critical concern in modern power systems due to the penetration of the wind and solar power plants as renewable energy sources (RESs), resulting in the reduction of inertia of generating units. Due to the short time duration and less operation cost, primary frequency regulation is given priority to low inertia grid to prevent from collapse or blackout along with reducing rate of change of frequency (RoCoF). Thermostatically controlled loads (TCLs) provide a significant spinning reserve due to their thermal inertia. Potato plays a vital role in food chain worldwide. For lack of preservation, the quality of potatoes is degraded and rot. In this proposed work, the rate of change of frequency of low inertia area of a two-area system is improved by using centralized direct load control of a population of potato cold storage for sudden power unbalance. A design of potato cold storage for this work is proposed. The virtual synchronous machine with cold storage model is simulated in MATLAB/Simulink in the proposed work. Different case studies prove the potential of using this method to improve rate of change of frequency in primary frequency regulation. In the proposed approach, the user’s comfort is sacrificed for very short time operation. The incentives given to customers to participate in demand response (DR) program by proposed method emphasizes the future work on different control strategies for fast frequency regulation.