Shed Parameters Optimization Of Polluted Contact Network Composite Insulator Based On Electric Field Distribution

Chinese high-speed rail has developed rapidly and has become chinese most beautiful business card.The reliable and stable operation of the catenary power supply system,which realize uninterrupted power supply to ensure the normal operation of the train.The catenary insulators play an important role in insulation and support of the power supply wire.Due to the low installation height,the catenary insulators are easily contaminated,and the flashover is caused under severe conditions.Composite insulators have superior flashover characteristics,which is related to the structural parameters of the shed.The fundamental mechanism of flashover is that the local electric field strength distortion causes arc,so the electric field and potential distribution are closely related to flashover.Experimental testing and numerical simulation are two ways to study electric field strength and potential distribution.The experimetal test period is long.The experimetal test result is affected by the test device and has a certain dispersion.With the development of computer technology,numerical simulation has become a mainstream means.At present,it is rare to use the numerical simulation method to study the shed parameters of the contact network insulators.Therefore,it is necessary to carry out simulation research on the shed parameters of catenary insulators under the contamination condition.The catenary composite insulator FQBG-25/16 is selected as the research object,which is rod-shaped column structure.According to the actual size parameters,the corresponding2 D simulation model is established in the finite element software Ansoft Maxwell,and the pre-processing settings of the model(material property parameters,excitation and boundary conditions,meshing and solution conditions)are completed.Conduct electric field calculation to obtain the electric field strength and potential distribution along the cleaning condition.On the basis of the cleaning model,the contamination simulation model of the insulator is obtained.Conduct electric field calculation to obtain the electric field strength and potential distribution,compared with the results of cleaning condition.It is find that the existence of pollution makes the electric field strength distortion of near the high pressure end and the low pressure end of insulator shed,and the distortion is more severe.According to the single variable method,the simulation model of distance between insulator sheds,big insulator shed extension distance,the difference entention distance values between big insulator shed and small insulator shed,large umbrella extension,the inclination of insulator shed are established.The influence of the structure parameters of the shed on the electric field strength and potential distribution is obtained by electric field calculation.Then,according to the main criterion(creepage coefficient and level electric field strength)and the auxiliary criterion(non-uniform coefficient),the shed structure parameter with better electricfield distribution characteristics is determined.Which can provide reference values of the shed parameters for experimental studies.