变速抽蓄机组失磁故障分析及保护研究  

Study on Loss of Excitation Fault Analysis and Protection of Variable Speed Pumped Storage Units

作　　者：卢庆辉 尹项根[1] 乔健[1] 王义凯 尹昕 Lu Qinghui;Yin Xianggen;Qiao Jian;Wang Yikai;Yin Xin(State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology,Wuhan 430074 China;School of Electrical and Information Engineering Changsha University of Science&Technology,Changsha 410114 China)

机构地区：[1]强电磁工程与新技术国家重点实验室(华中科技大学),武汉430074 [2]长沙理工大学电气与信息工程学院,长沙410114

出　　处：《电工技术学报》2024年第5期1390-1403,共14页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(52007010);中央高校基本科研业务费专项(HUST:YCJJ202202020)资助项目。

摘　　要：变速抽蓄机组(VSPSU)的励磁及控制方式复杂且易发生失磁故障,配置针对性的失磁保护对保障其安全运行至关重要。该文基于直流励磁系统和交流励磁系统的差异分析,将VSPSU的失磁故障划分为对称失磁和不对称失磁两种故障形式,并主要针对对称失磁故障开展研究。首先,分别从故障位于机侧和网侧角度出发分析VSPSU发生对称失磁故障后的电气量变化特性及其故障危害;然后,推导证明了传统失磁阻抗圆保护判据在VSPSU中应用时不具有可靠性,VSPSU缺乏具有针对性的保护方案;最后,基于VSPSU的失磁故障特性,提出了针对机侧对称失磁故障的下抛阻抗圆判据和针对网侧对称失磁故障的直流电压判据,两者结合形成了对VSPSU对称失磁故障的保护方案。仿真结果表明,该文所提方案可有效地检测VSPSU在各种运行工况下的对称失磁故障,以满足VSPSU对失磁保护可靠性的要求。The excitation and control methods of variable speed pumped storage units(VSPSU)are complex and prone to the loss of excitation(LOE)fault.Therefore,it is very important to configure targeted protection to ensure its safe operation.Due to the special three-phase AC excitation method used in VSPSU,its LOE fault is quite different from that of conventional units.At present,the LOE protection scheme of the traditional DC excitation synchronous machine is relatively mature,but there are few studies on the LOE fault characteristics and LOE protection of the AC excitation doubly-fed machine,and a reliable protection scheme has not yet been formed.To ensure the safe operation of VSPSU,this paper analyzes the characteristics of the LOE fault of the VSPSU in detail and puts forward the corresponding LOE fault protection scheme on this basis.Firstly,based on the difference analysis between the DC excitation system and the AC excitation system,the LOE fault of VSPSU is divided into two types:symmetrical LOE and asymmetrical LOE,and the research is mainly carried out on the symmetrical LOE.Secondly,the fault characteristics and fault hazards of VSPSU symmetrical LOE are analyzed from the point of view of the fault located on the machine side and the grid side,respectively,and the importance of configuring LOE protection for VSPSU is clarified.Then,the adaptability of the traditional LOE protection criterion based on impedance circle when applied in VSPSU is deduced and analyzed.Finally,based on the characteristics of the operating power of the VSPSU after LOE and the corresponding relationship with the impedance,the criterion of the downward throwing impedance circle is proposed for machine-side symmetrical LOE fault;based on the reflection characteristics of DC voltage on the damage of rotor-side power exchange channel, a DC voltage criterion for grid-side symmetrical LOE fault is proposed. The combination of the two forms a protection scheme against the symmetrical LOE fault of the VSPSU. The research has the following conc

关 键 词：变速抽蓄机组 交流励磁 失磁故障 失磁保护 保护可靠性 

分 类 号：TM312[电气工程—电机]