Research On Suppressing Inter-area Low Frequency Oscillations By Using Remote PMU Signals

The low frequency oscillations of regional pattern seriously threat the safe operation of interconnected power especially. Compare with PSS, configuration and parameter calculation of GPSS is simple, its effect is fairly well, so we can use inter-area signal for GPSS. Besides, load change or AGC adjustment can also cause oscillation. Nowadays, rotor Angle control technology provides a new possibility to suppress low frequency oscillation and reduce tie line power fluctuations.Study the Scope of network transmission delay and its influencing factors; analyze the corresponding time delay effect on the GPSS control.Study the possibilities of using the inter-area signal combined with GPSS suppresses regional low frequency oscillation.Study the possibilities of rotor Angle controller using the distant signal suppresses low frequency oscillation and tie line power fluctuation.This article conducts theoretical analysis mainly through calculating damping torque and synchronous torque. Furthermore use UD function of PSASP to test GPSS and rotor Angle controller. Effect of Rotor Angle controller/AGC is mainly completed through the theoretical analysis and mathematical deduction.Analysis of the existing SDH network delay shows that PMU signal can be shortened as long as local signals. In addition, with the development of high speed switching technology, you can ignore the influence of network delay. While choose the installation location and set the parameters configuration, GPSS can suppress the regional of low frequency oscillation. Set rotor Angle controller in right place and using the PMU signal controller, can effectively suppress low frequency oscillation. at the same time, also can reduce the tie line power fluctuation.Using GPSS or rotor Angle controller to suppress low frequency oscillation is feasibility and rationality of concrete. In fully excavate potential or existing SDH network, it can be put into practical. Compared rotor Angle controller to GPSS, it also has important practical significance.