Optimization on the Control Mode of Thermal Power Unit to Suppress Low Frequency Oscillation of Power System

Due to the randomness of its occurrence in power system, currently there is no effective way to suppress the low frequency oscillations through the existing thermal control modes of generation units. Based on the two specific study cases, this paper analyzes the process of thermal power units participating in low-frequency oscillation and then summarizes them in common. Arising from the observation of significant discrepancies between the turbine speed signal and the power grid frequency signal during the oscillation, an optimization method is proposed to suppress the forced oscillation by virtue of the control mode of thermal power unit. Additionally, it is suggested to replace the speed signal with the power grid frequency signal for the primary frequency modulation.