蓄能水电厂发电机保护CT误差曲线校核计算判据及应用

The criterion and application to check and calculate the generation protection's CT error curve of the pumped storage power station

当一次系统故障产生最大短路电流时,为了使保护装置能够正确反应一次系统状况而正确动作,电流互感器的变比误差必须在一定范围内。大型蓄能水电厂发电机保护CT数量多,且CT的规格型号也不一样,本文列出判断CT误差曲线是否合格的3种判据,计算并校核了某蓄能水电厂实测的发电机保护CT误差曲线,验证曲线结果正确。本文的计算校核方法为蓄能水电厂保护CT误差曲线校验提供了验证方法,具有实践指导意义。

The ratio error of current transformer must be within a certain range, to ensure the relay protection device have a correct reaction to the system conditions when a failure occurs in the system equipment and it produces maximum short circuit current. There are numbers of generation protection CT in the large pumped storage hydropower station. The specifications and the models of the CT are different. This article lists three criterions to judge whether CT error curve is qualified, calculates and checks those CT error curve measured in the large pumped storage power station, and proves the results are correct. The calculation method of this paper provides a verification method for the protection of the CT error curve of large pumped storage power station, and have a practical significance to those station.