摘要
海洋核动力平台运行环境恶劣,发电机定子接地故障频发,故障严重时将损伤定子铁心,但盲目快速切机会导致核反应堆负荷失电,威胁平台安全运行。为保证发电机自身安全及核反应堆负荷供电安全,该文提出基于双频电压调控的发电机定子接地故障有源消弧及辨识方法。基于电压补偿型消弧原理,在发电机中性点外加包含基波及3次谐波分量的电压源,通过控制输出电压与故障电动势幅值相等、相位相反,抑制故障点电压为零,实现有效熄弧。在辨识接地故障类型时,与接地故障安全风险分析相结合。安全风险高的情况下,调节外加基波电压的同时控制接地故障电流在安全电流范围内,并利用瞬时性和永久性接地故障条件下中性点基波零序电流和基波零序电压间相位差的差异构建故障辨识判据。仿真和动模实验结果验证了所提方法的有效性。
The operation environment of floating nuclear power plant is harsh, and the generator stator ground fault occurs frequently. When the fault risk is serious, the stator iron core will be damaged, but blind cutting will lead to power loss of important loads, threatening the safe operation of the plant. This paper presents the method of stator ground fault arc elimination and fault type identification based on dualfrequency voltage regulation. Firstly, based on the arc elimination principle of voltage compensation, a voltage source containing fundamental and third harmonic components is applied to the generator neutral point. Its output voltage is controlled as the same amplitude and opposite phase with the fault electric potential, then the voltage at the fault point is suppressed to zero to achieve effective arc extinguishing.Ground fault type identification is realized combining with ground fault safety risk analysis. Under high risk conditions, at the same time of adjusting the fundamental injection voltage, the ground fault current is controlled within the safety current range. The instantaneity and permanent ground faults are identified based on the criterion of phase difference between the fundamental zero-sequence current and the neutral point voltage. Simulation and dynamic test results verify the effectiveness of the proposed method.
作者
王义凯
尹项根
谭力铭
乔健
尹昕
Wang Yikai;Yin Xianggen;Tan Liming;Qiao Jian;Yin Xin(State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology,Wuhan 430074 China;Hubei Electric Power Security and High Efficiency Key Laboratory Huazhong University of Science and Technology,Wuhan 430074 China;School of Electrical and Information Engineering Changsha University of Science&Technology,Changsha 410114 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2022年第19期4835-4847,共13页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(52007010)
国家重点研发计划(2017YFC0307800)资助项目。
关键词
海洋核动力平台
双频电压调控
定子接地故障
有源消弧
故障辨识
安全电流
Floating nuclear power plant
dual-frequency voltage regulation
stator ground fault
active arc suppression
fault type identification
safety current
