Power System Oscillation Mode Analysis and Parameter Determination of PSS Based on Stochastic Subspace Identification

Advanced mathematical tools with the potential to identify and characterize these dynamics in near real time have been applied very successfully to power system.This paper introduces the stochastic subspace identification(SSI) to the analysis of power system low frequency oscillations,and the power system stabilizer can be designed to use the results of identification and residue .This method can overcome the incapability for the Prony and ARMA algorithm effected by signal noise and system orders.And at the same time,the complex process of identification and the long time of calculation in the HHT transformer can be dealt with. Using the SSI method,the oscillatary information can be obtained accurately from signal containing noise.And the parameters of PSS can be designed only by using the observation signal. This method can be used to power system low frequency oscillations on-line identification and control.The real test data and simulation results show that this method is a highly effective tool for power system low frequency oscillations.