Research on Variable Inertia Coordination Frequency Regulation Strategy Based on a Wind & Thermal Power Combined System

Abstract

With the increasing installed capacity of the wind power, the power system has an obviously low inertia characteristic. It is of great significance to actively promote the virtual inertia frequency regulation technology of wind turbines (WTS) for improving the system frequency quality. The frequency regulation capability and frequency regulation effects of wind & thermal power units were analysed, and a variable inertia coordination frequency regulation strategy for different wind power penetration conditions was proposed in this paper. At the wind farm level, the dynamic frequency regulation participation coefficient of wind farms was fuzzily determined according to the operation conditions of WTS and the wind power penetration ratio. At the wind turbine level, the calculation method of the equivalent inertia constant of WTS was given based on the effective rotational kinetic energy. And the allowable range of frequency regulation parameters of WTS was determined by considering the incremental model of the system. Results indicated that the proposed coordinated frequency regulation strategy not only provided a reliable inertia support, but also maintained the stability of WTS. The frequency response performance of the high-penetration wind power system was improved.