母线差动保护比率制动系数整定分析及应用

根据母线差动保护制动特性原理，对各种电网工况下比率制动系数的影响因素进行分析，通过对不同制动系数的计算给出其整定方案，即母线并列运行时，取高值0．7，考虑电流互感器（currenttransformer，CT）传变误差的情况和母线流出电流的情况时取低值0．3；提出在母线差动保护装置中将比率制动系数定值进行固化的建议，简化了母线差动保护的整定，提高了整定计算的安全性和整定工作效率。

Analysis and Application of Ratio Restraint Coefficient Setting for Bus Differential Protection

According to principle of restraint characteristics of bus differential protection,the paper analyzes affecting factors of ratio restraint coefficient in various operating condition of power grid.By calculation on different restraint coefficients, the paper proposes a setting scheme:in case the buses operate in parallel,choose the maximum 0.7 while choose the minimum 0.3 in consideration of transfer errors of current transformer(CT) and flowing current from the bus;it proposes a suggestion of fixing ratio restraint coefficient value for bus differential protection,simplifying setting for bus differential protection and improving safety of setting calculation and setting efficiency.