高压直流转换开关避雷器改造方案研究  

Research on the Modification Plan of HVDC Transfer Switch Arrester

作　　者：卢毓欣 赵晓斌 秦康 徐迪臻 辛清明 郭龙 LU Yuxin;ZHAO Xiaobin;QIN Kang;XU Dizhen;XIN Qingming;GUO Long(State Key Laboratory of HVDC,Electric Power Research Institute,CSG,Guangzhou 510663,Guangdong,China)

机构地区：[1]直流输电技术国家重点实验室(南方电网科学研究院有限责任公司),广东广州510663

出　　处：《南方能源建设》2022年第1期76-85,共10页Southern Energy Construction

基　　金：南方电网公司科技项目“500kV直流工程标准化成套设计方案研究”(ZBKJXM20180722)。

摘　　要：[目的]国内高压直流输电工程在进行单极大地/金属运行方式转换时,曾发生过数次MRTB (金属回线转换开关)或ERTB (大地回线转换开关)振荡平台避雷器损坏导致转换失败的情况。因此需要对直流转换开关避雷器几种改造方案进行研究。[方法]针对直流转换开关避雷器吸收能量高、通流时间长以及压比较高的特点,本文从避雷器吸收能量、通流时间和过电压等的计算结果判断增加避雷器柱数和每柱串联阀片数两种改造方案能否改善避雷器的运行环境,并分析了对其他相关设备绝缘水平的影响以及对设备布置的影响。[结果]增加避雷器柱数对改善避雷器运行特性无明显作用。增加避雷器单柱片数可降低避雷器通流时间,但将提高断路器和振荡回路电容器绝缘水平。[结论]不建议对现有换流站直流转换开关避雷器进行增加避雷器柱数或片数的改造。可在较低功率水平下进行转换以降低避雷器应力。若避雷器能量裕度足够,在因阀片缺陷引起避雷器故障的情况下可采取拆除故障台并继续运行的措施。[Introduction] During the earth return and metallic return mode conversion of China’s HVDC transmission projects in operation, several MRTB(metallic return transfer breaker) or ERTB(earth return transfer breaker) oscillation platform arrester damage have occurred, leading to conversion failure. Therefore, it is necessary to study several modification plans of DC transfer breaker arrester. [Method] Regarding the characteristics of high energy absorption, long current flow time and high ratio of residual voltage to reference voltage of the DC transfer switch arrester, the calculation results of the arrester’s absorbed energy, flow time and overvoltage were proposed to judge whether the two modification plans of increasing the number of arrester columns and increasing the number of valves in series per column could improve the operation environment of the arrester, and the impact on the insulation level of other equipment and the arrangement of equipment were also analyzed in this paper. [Result] Increasing the number of arrester columns has no obvious effect on improving the operation characteristics of the arrester. Increasing the number of valves in series per column can reduce the current flow time of the arrester but will increase the insulation level of the circuit breaker and the capacitor of the oscillation circuit. [Conclusion] It is not recommended to increase the number of columns or the number of valves in series per column of the HVDC transfer switch arrester in the existing converter station. It can be transferred at a lower power level to reduce the stress of the arrester. If the energy margin of the arrester is sufficient, measures can be taken to remove the faulty unit and continue operation in the event that the arrester fails due to valve defects.

关 键 词：直流转换开关 避雷器 吸收能量 通流时间 过电压 

分 类 号：TM7[电气工程—电力系统及自动化] TM564