The Analysis And Comprehensive Elimination On Guyuan Power System Harmonic

Non-linear loads such as frequency devices,rectifier device,especially the electrified railway immit a large number of high harmonics into the power system, which make the harmonic voltage,voltage fluctuations and flicker,and three-phase voltage imbalance become more and more serious.High harmonics not only affects the security of electricity,but also deteriorates the power quality;increases power loss,and leads electrical equipment works abnormal,part of the normal operation of protection devices should not run,even can not run,the power incident increase.Therefore the quality of comprehensive management is imperative.In order to test the power system and the harmonic level of harmonic source compliance with the standards,to reduce the impact of harmonic on the power grid, Using the portable power quality analyzer PS2 measure voltage and current,intervals for 5 minutes in 3 hours in the real-time measurement way.Aanalyse the measurement results,the rate of voltage distortion and harmonic currents excessive caused by the electrified railway.The common methods of harmonic detection have the instantaneous reactive power of the detection methods;the wavelet transform detection methods,the detection based on neural network methods and the Fourier transform.Using the Fourier simulates the entire Guyuan 110kV power grid in Matlab,Simulation results shows that interpolation algorithm based on the Fourier transform is a good method of eliminating spectrum leakage and barrier effect.Analysis SVC work principle which according to reactive power demand or voltage changes realizes automatic tracking compensation,and control systems which including the voltage,current measure,voltage regulator and synchronous trigger pulse.According to the actual situation of the Guyuan power grid put forwards the program of harmonic control,that is,installe TCR+FC type SVC compensation device which has 3,5,7 filter banks in Guyuan 27.5KV sides.Simulating the program, analysis 3,5,7 harmonic current,voltage distortion rate before and after compensation.The results shows that harmonic currents were significantly reduced and harmonic distortion rate is lower than the national standard,SVC can effectively suppress harmonic.