将现代故障通行标准纳入配电网络的短路计算中.
Evangelos E Pompodakis1, Yiannis Katsigiannis2, Emmanuel S Karapidakis2
1Institute of Energy, Environment and Climatic Change, Hellenic Mediterranean University, 71004 Heraklion, Greece.
Sensors (Basel, Switzerland)
|November 14, 2023
概括
现代故障通行标准意味着短路电流的变化,使保护装置触发时间的计算复杂化. 这项研究通过计算分布式发电机的电网中的这些动态故障电流来提高准确性.
科学领域:
- 电气工程 电气工程
- 电力系统分析 分析 分析
- 整合可再生能源的整合
背景情况:
- 现代故障通行 (FRT) 标准要求分布式发电机 (DGs) 在故障期间保持连接,提供反应电流以稳定电压并防止广泛的停电.
- 这种FRT要求导致时间变化的短路电流,因为DG的贡献根据故障条件和断开序列而变化.
- 传统的短路计算方法通常假设恒定故障电流,这对于具有高可再生透率的现代电网是不准确的.
研究的目的:
- 开发和验证一种包含现代FRT标准的故障分析方法,考虑到短路电流的动态性质.
- 准确估计电力系统中的超电流保护装置 (继电器和保险丝) 的触发时间,这些系统具有重要的 DG 集成.
- 突出FRT符合电网的传统恒定故障电流假设的不准确性.
主要方法:
- 将现代FRT标准纳入故障电流分析.
- 时间变化的短路电流受GD在故障过程中的行为影响的建模.
- 在13个总线网络和IEEE 8500节点网络上进行模拟研究,以评估保护装置触发时间.
主要成果:
- 该研究表明,故障电流变化显著影响保护装置触发时间.
- 传统的短路计算方法,假设电流恒定,可能导致触发时间的大量误算.
- 模拟显示,在遵守现代FRT标准的网络中,触发时间估计高达80秒的潜在偏差.
结论:
- 现代电力系统的准确故障分析需要考虑FRT标准规定的动态短路电流.
- 拟议的方法提高了保护装置触发时间估计的精度,这对于电网可靠性和保护协调至关重要.
- 如果不考虑FRT影响的电流变化,可能会损害高可再生能源电网的超电流保护性能.
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