Estimation of Wind Penetration in a Thermal Dominated Power System Limited by Frequency Deviation

Abstract

This paper describes a wind-thermal power system on the analysis of the frequency response characteristics of thermal generators and wind turbines (WTs) against the imbalanced power. The composite transfer function of the speed governing system is proposed on the basis of the speed governor’s model, and the time-domain expression of the frequency deviation against the perturbation of electrical power is given in this paper. This paper studies the maximum surplus power (Ps,m) and the maximum deficit power (Pd,m) in a thermal dominated power system to avoid the action of OPC and UPLS. Considering the wind farm (WF) power injected to the existing power system, the wind penetration level (LP) has great effects on the Ps,m and the Pd,m. Through theoretical calculation and the simulation of a power system that consists of a thermal unit and GE wind turbines, this paper draws this conclusion that with the increase of the wind penetration level, Ps,m will increase in a liner relation and Pd will decrease in a hyperbolic relation.