On-site DC Dielectric Test of ±800kV DC Equipment

Abstract: The paper presents first on-site DC dielectric test of ±800kV UHVDC equipment in ±800kV UHVDC project, which is carried out at the converter station. It can provide a reference for similar tests and researches in the future. The test scheme and test data are analyzed. The least squares of two models are utilized to perform fitting of test data and volt-amphere characteristics of DC dielectric test of ±800kV UHV equipment are obtained. It is found that it accords with the function of quadratic polynomial, and the initial voltage of non-linearity strong corona is about 400kV. The test results verify the volt-amphere characteristics of on-site DC dielectric test and the influence of connection mode, safety distance and altitude on test results. 

Key words:  UHV, DC dielectric test, test scheme, function of volt-amphere characteristics, test equipment, wiring method    

It is the first time for a ±800kV UHV equipment to be used in the some UHVDC transmission project. How to test its insulation status before use poses a new challenge for HV technology sector. Through unremitting efforts of related experts, scientific and technical staff, an Outline of Handover Test for xx-xx±800kV DC Equipment is officially issued, which provides a basis for UHV equipment. Although the withstand voltage test is performed on ±800kV UHV equipment before leaving the factory, an Outline of Handover Test for xx-xx±800kV DC Equipment and relevant standards should be strictly adhered to examine the insulation status after transport and installation. The  withstand voltage test must be carried out on site for the UHV equipment. The paper presents the DC dielectric test of ±800kV UHV equipment of UHVDC transmission project.