Improvement of Frequency Stability in the Power System Considering Wind Turbine and Time Delay

In the power system, frequency stability is critical. The wind turbine oscillates (depending on the wind speed) and is of low inertia. Thus, wind turbines face the issue of power system frequency stability. Since the power system's resources are interconnected via communication networks, the presence of time delay also affects the frequency stability of the power system. When a disturbance occurs in the power system due to load or distributed generation sources (wind turbine), it leads to frequency deviations in the power system, exhibiting low damping speed. Although large conventional generators in the power system provide sufficient inertia and reduce frequency deviation, the damping speed of frequency fluctuations is slow, which may be due to time delays between power system resources. In this paper, virtual damping (a proposed method) is used to accelerate the damping of frequency deviations caused by load disturbances, distributed generation source disturbances, and the time delay between power system resources. The results of the proposed method are compared to those obtained using the conventional method in this field, demonstrating the superiority of the proposed method. The proposed method reduced frequency deviations in the power system caused by disturbances and time delays by ۶۷ % (a ۶۷ % improvement over existing methods in this field) and increased the damping speed of the frequency deviations by ۶۲ % (a ۶۲ % improvement over the methods used in this field).

Keywords:

Wind Turbine , Time Delay , Load-frequency control , Virtual damping , Power system