摘要
发电厂内广泛采用3/2接线的500 kV系统,经过经济技术论证合理时,500 kV并联电抗器可接入串内。由于并联电抗器额定电流较小而串内可能的穿越电流较大,典型的电流互感器(Current Transformer,CT)配置方案无法满足保护装置可靠性和灵敏性的要求。改进的保护CT配置方案需在分支上增加两组CT,设置电抗器引线保护和电抗器本体保护,分别用于保护断路器、分支部分和电抗器本体部分。通过详细分析和计算,证明改进的保护CT配置方案是可行的。
The ＂3/2＂ connection and 500 kV voltage system are widely used in power plants. The shunt-wound reactors can be connected in series after economical and technical analysis. The rated current of shunt-wound reactors is much less than the possible cross current within the series. So the typical protective CT scheme can＇ t satisfy the reliability and sensibility requests of protection devices. In the improved protective CT scheme, two sets of CT need be additionally provided in the offset. The offset protection and reactor protection are provided for protecting the part of circuit breakers, offset and the part of reactor. The improved protective CT scheme has been proved to be feasible through detailed analysis and calculations.
出处
《电力勘测设计》
2015年第4期28-31,共4页
Electric Power Survey & Design
