可控换相换流阀单阀关断试验方法研究  

Study on Single Valve Turn-off Test Method of Controllable Line-commutated Converter

作　　者：贺之渊 高冲 张娟娟 盛财旺 王成昊 王蒲瑞 HE Zhiyuan;GAO Chong;ZHANG Juanjuan;SHENG Caiwang;WANG Chenghao;WANG Purui(State Key Laboratory of Advanced Power Transmission Technology(China Electric Power Research Institute),Changping District,Beijing 102200,China)

机构地区：[1]先进输电技术国家重点实验室(中国电力科学研究院有限公司),北京市昌平区102200

出　　处：《中国电机工程学报》2024年第20期8248-8257,I0027,共11页PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING

基　　金：国家重点研发计划项目(2021YFB2400900)。

摘　　要：可控换相换流阀(controllable line-commutated converter,CLCC)既保持着常规直流换流阀容量大、损耗低、过负荷能力强的优势,又能实现桥臂可控关断,可根本解决换相失败问题,适用于多馈入直流系统。2023年6月,CLCC已成功在±500 kV/1 200 A葛南直流改造工程中示范应用,投运以来运行性能良好。CLCC关断大电流的能力决定了其是否能够在交流故障时成功抵御换相失败,因此,需开展单阀大电流关断试验,验证换流阀实际交流故障下内部百余支可控器件同步开通、关断一致性及暂态电气应力耐受水平。该文基于CLCC交流故障时的强迫换相原理,首先分析了主辅支路换流及桥臂换流过程中IGBT子阀关键应力,提取了故障工况各阶段的关键应力参数。其次,提出百kV补能交流电压源和LC谐振电流源百毫秒投退及隔离控制试验方法,建立了关键应力参数与试验电路参数的解析关系,完成了试验电路参数设计。搭建了±500 kV/1 200 ACLCC单阀大电流关断试验平台,考核了换流阀的工作能力,又通过试验和仿真对比分析验证了试验方法的等效性和正确性,为后续不同电压等级CLCC单阀关断试验的提供理论指导。The controllable line-commutated converter(CLCC)not only inherits the advantages of large capacity,low loss,and high overload capacity of traditional line commutated converter(LCC),but also has the ability to shut off the bridge arm actively,which can fundamentally prevent commutation failure.In June 2023,the CLCC valves were successfully applied in the±500 kV/1200 A Genan DC renovation project,and since operation the operating characteristics have been good.The ability of turning off high current for the CLCC valve determines whether it can successfully withstand commutation failure in the event of AC faults.Therefore,it is necessary to carry out a single valve large current turn-off test to verify the synchronous turn-on and turn-off consistency and the transient electrical stress tolerance level of more than 100 controllable devices in the CLCC valves under AC failure.Based on the principle of forced commutation process in the case of AC failure of CLCC valves,this paper firstly analyzes the key stress of IGBT sub-valve during the main-auxiliary branch transfer and bridge arm forced shutdown process,and extracts the key stress parameters in each stage.Secondly,using hundred-millisecond back-off and isolation control method of the hundred-kV supplementary AC voltage source and LC resonant current source,a high current turn-off test device for single CLCC valve is developed,the analytical relationship between key stress parameters and test circuit parameters is established,and the parameters of the test device are designed.A large current turn-off test platform for a single±500 kV/1200 A CLCC valve was built to evaluate the working capability of the CLCC valves,and the equivalence and correctness of this method were verified through comparison between experiments and simulation.The method can also provide theoretical guidance for the subsequent single valve turn-off test of CLCC valves with different voltage levels.

关 键 词：可控换相换流阀 强迫换相 单阀关断应力 试验方法 参数设计 

分 类 号：TM732[电气工程—电力系统及自动化]