Modeling and evaluation of short-term frequency control for participation of wind farms and energy storage in power systems

With an increasing penetration of wind powerin isolated power systems, short-term frequency control is becoming a particular concern due to the reduction of system inertia and primary frequency regulation capacity. This paper presents a new average system frequency response (SFR) model with participation of wind farms and energy storage systems (ESSs) in frequency control. Based on this model, maximum rate of change of frequency (ROCOF) and maximum frequency deviation are calculated. Such two transient frequency indexes are used to guide adaptive participation of the ESS in the frequency control through a lookup table. The proposed model and frequency control method can provide an appropriate evaluation to the participation of wind farms and ESSs in the short-term frequency control of isolated power systems. Sudden load changes and wind power fluctuations are used to test the system frequency responses. The calculation results verify the validation of the proposed model and frequency control method.