Study On Synchronized Measurement Method For Renewable Power Station

With the development and utilization of large-scale renewable energy and the operation of all kinds of power electronic equipment in the system,the mechanism characteristics,analysis methods and operation control methods of power system have all changed fundamentally in the renewable energy area.The existing measuring devices do not have the ability of synchronized measurement,and their uploading rates are low,which cause that it’s difficult to dynamically monitor the complex electrical signals in renewable energy area.Therefore,it is of great significance to study a synchronized measurement method for complex electrical signals in renewable energy station.The renewable energy may generate a large number of sub/super-synchronous harmonics,which leads to sub-synchronous oscillations(SSO)when inter-harmonic’s frequency is complementary with the natural frequencies of thermal power generator shafts.Aiming at the problem of measuring the harmonics/inter-harmonics in renewable energy station,the errors of fast Fourier Transform(FFT)and the mutual interference between components are analyzed,then a spectral line curve fitting based algorithm for inter-harmonics measurement is proposed.Under the influence of power electronic equipment,the electrical signals in renewable energy stations show the characteristics of broadband,multi-transient,high noise,complex dynamic process and so on.Aiming at the problem that the phasor measurement in the renewable energy area needs to balance the measurement accuracy and the dynamic response speed,a multi-frequency dynamic signal model is built,singular value decomposition is used to reduce noise,and a matrix pencil based fast phasor measurement algorithm is proposed.Aiming at the problem of real-time dynamic monitoring for renewable energy station,a kind of synchronized measurement device for renewable energy station(SMD-R)is developed.Then a laboratory testing platform is developed to verify the accuracy of SMD-R.Experiment results indicate that the precision meets the requirements of P-class PMU in the standard IEEE C37.118.1 and the response speed is higher than the standard requirements greatly.Finally,field data is used to verify the effectiveness of the device.