Research Of±500kV Converter Transformer Maintenance

The Extreme High Voltage or Ultra High Voltage Direct Current (EHV/UHVDC) powersystem will effectively improve the transmission capacity of the power grid because of itslarge capacity, high efficiency and long transmission, which is of importance to ensure ourcountry’s economic development rapidly and social harmony and stability. Southern powergrid company focus the strategic target and work on the development of EHV/UHVDCtransmission technology and the construction of UHV power transmission project. Southernpower grid has proposed to speed up the construction of1000kV AC and±800kV DC UHVpower grid in order to build up strong UHV transmission network as its core. At present,Guangdong main channel of the power transmission in West to East has already formed the"six AC and three DC" strong network structure, and make effort to realize the major net rackof "eight AC and five DC". As converter transformer, whose security and reliabilitydirectly affect the operation state of HVDC, is one of the most important and expensiveequipment in the transmission system, making research on overhauling technology oftransformer is of great significance to improve safety and reliability of the equipment andeven the power grid.Guangzhou UHV test research and maintenance base have hardware preparation forearly research, operation and maintenance. In the meantime, it provide the significanttechnical support for equipment operation, maintenance and test research of Southern powergrid UHV. Its maintenance hall will be the UHV equipment overhaul base of South China,which provide overhaul and experimental base and the platform of fault analysis andoperation features research for UHV converter transformer, power transformer and switch,etc., as well as the technical support and services for the safe operation, maintenance, training,of power grid etc.In this article, for converter transformers belonging to the UHV Transmission CompanyCSG, technical content of transformer maintenance in the hall is studied, as well as themethods improving the maintenance efficiency, through the large domestic transformermanufacturers’ investigation and massive acquisition of information. Technical requirementsabout design and function of maintenance hall are proposed, involving technical parameters,equipment configuration and so on.This article studied the maintenance workflow and the requirement of technology controlfor±500kV converter transformer carried out within the hall. The site planning, spacerequirements, working environment requirements, the type and quantity of common tooling equipment requirements and the large equipment requirements are also contained in thisarticle. The results of this research can provide the basis for±500kV converter transformermaintenance carried out in Guangzhou EHV test base.