为双极LCC HVDC线路扩展基于极差电流的继电
Ravi Shankar Tiwari1, Jai Prakash Sharma1, Om Hari Gupta2
1Department of Electrical Engineering, GLA University, Mathura, Uttar Pradesh, 281406, India.
Scientific reports
|May 9, 2025
概括
本研究介绍了基于线路换算转换器的高压直流 (LCC-HVDC) 传输系统的新中继方法. 该方法使用极差电流 (PDC) 进行快速可靠的故障检测,增强系统安全性.
科学领域:
- 电气工程 电气工程
- 电力系统工程 电力系统工程
背景情况:
- 高压直流 (HVDC) 传输系统面临远距离,恶劣环境和快速直流线路故障的挑战.
- 在直流线路中的高故障电流可能会对电源设备造成不可逆转的损坏,需要强有力的保护.
研究的目的:
- 为LCC-HVDC传输系统开发快速可靠的线路保护和隔离方法.
- 提高LCC-HVDC系统对直流线路故障的安全性和可靠性.
主要方法:
- 结合了在直流线路边界的单端和双端过渡电流测量.
- 分析极流的时间域响应,以定义本地和全球极差电流 (PDC).
- 开发了使用PDC用于双极和单极LCC-HVDC操作的中继标准.
主要成果:
- 拟议的方法可以在双极运行时在5.1毫秒内实现快速故障检测,而单极运行时在15.6毫秒内.
- 准确地识别错误的极点,而无需对双极模式进行同步,并证明对过渡电阻的强度.
- 通过使用PSCAD/EMTDC和MATLAB/Simulink在2000MW,±500kV,900km双极LCC-HVDC系统上的模拟验证.
结论:
- 基于PDC的继电方案为LCC-HVDC线路保护提供了快速,可靠和无同步的解决方案.
- 该方法有效地提高了LCC-HVDC传输系统的安全性和可靠性.
- 该研究提供了一种有效的方法来保护关键电力基础设施.
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