发电机失步保护整定计算所用的等值联系电抗X_(con)研究——与现行《大型发电机变压器继电保护整定计算导则》商榷

Research on equivalent contact reactance X_(con) setting calculation for generator out-of-step protection——discuss with Guide of Calculating Settings of Relay Protection for Large Generator and Transformer

现行《大型发电机变压器继电保护整定计算导则》有关发电机失步保护整定计算中发电机机端与无限大系统间的等值联系电抗Xcon的计算公式欠妥,值得商榷。对此问题进行深入分析,得出发电机失步保护整定计算中所用的Xcon正确的计算方法。并在同一系统振荡工况下依照该计算方法所得的Xcon值与依照《导则》的计算方法所得的Xcon值进行对比分析,分析结果表明:《导则》的整定计算方法极可能导致失步保护拒动,而所提整定计算方法能确保失步保护可靠动作。

The calculation formula of equivalent reactance Xcon between generator and infinite system for generator out-of-step protection in the current ＂ Guide of Calculating Settings of Relay Protection for Large Generator and Transformer＂ is improper, it is questionable. This paper has researched this problem deeply and obtained the correct method of the Xeon setting calculation for generator out-of-step protection, and compared the Xeon values calculated by the proposed calculation method and the ＂ guidelines ＂ calculation method in the same oscillation of the system condition, the results show that the ＂guidelines＂ setting calculation method may lead to the out-of-step protection maloperation, and the proposed setting calculation method can ensure the out-of-step protection reliable operation.