变压器变斜率比率制动差动保护校验探讨

Discussion on Check of Power Transformer Variable Slope Ratio Restraint Differential Protection

针对变压器变斜率比率制动差动保护制动方程较复杂,校验较困难的问题,从数学角度深入分析各电流之间的数量关系,简化差动电流、制动电流和测试电流之间的关系,提出一种变斜率比率制动差动保护校验的方法,并结合Excel自动计算表格,可以快速准确校验保护的动作曲线,提高校验准确度和校验效率。通过某电站的校验实例验证该方法快捷、准确,接结简便,易于操作,可以校验保护装置的整个工作状态。

Considering that the transformer variable slope ratio restraint di{ferential protection braking equation is rather complicated and its check is quite difficult, the paper analyzes the quantitative relation be tween various currents, simplifies the relations between the differential current, the braking current and the test current and proposes a variable slope ratio restraint differential protection check method from the angle of mathematics. Further the paper uses the Excel automatic calculation form to check the activation curve of the check protection in a quick and accurate way to improve both check accuracy and check effi ciency. The check living example of a certain hydropower plant proved that the method is quick, accurate, easy to do connection and to operate and is able to check the whole working condition of the protection de vice.