Research On Dielectric Loss Factor Measurement Algorithm Combining PSO-VMD With Sine Wave Parameter Method

With the continuous development of social economy.the demand for electric energy in industry and life is increasing.How to ensure the stable and safe operation of the power system has become the most important issue of the power system.There are a large number of high-voltage electrical equipment in power system,and the damage of insulation material is the main cause of high-voltage electrical equipment accidents.In order to avoid accidents,the state of insulating materials must be tested.Dielectric loss factor is an important parameter reflecting the state of insulating materials.Therefore,it has great significance to study the calculation method of dielectric loss factor.The mechanism of dielectric loss is introduced,and the advantages and disadvantages of various methods for measuring dielectric loss factor are analyzed by consulting a large number of literatures.It is concluded that the measurement accuracy of dielectric loss factor is susceptible to harmonics and noise.Therefore,how to extract the fundamental component of voltage and current accurately and reduce the influence of harmonics and noise on measurement results has become the key of the research.To solve the above problems,the particle swarm optimization variational mode decomposition algorithm(PSO-VMD)and sine wave parameter method are combined to measure dielectric loss factor.Firstly,particle swarm optimization(PSO)is used to optimize the two parameters of variational mode decomposition(VMD)algorithm:penalty factor a and decomposition layer K.According to the content of the study,the suitable fitness function is selected,and the optimized algorithm is used to extract the fundamental wave of current and voltage signals.Secondly,the optimized PSO-VMD algorithm and sine wave parameter method are used to calculate the dielectric loss factor.Through computer simulation,the measurement accuracy of this algorithm is analyzed in the case of frequency fluctuation,dielectric loss angle variation,harmonic interference,sampling frequency variation and white noise interference when measuring dielectric loss factor.It is verified that this algorithm has higher measurement accuracy,can effectively suppress the interference of harmonic and noise,and fully meet the measurement accuracy requirements.Finally,the LabVIEW MatScript script and MATLAB statements are combined to develop the display interface and acquisition system.The developed system can display the original waveform of voltage and current,extracted fundamental waveform and finally obtained measure value through calculating.