Research on capacitive current compensation of differential protection on segment parallel lines for different voltage levels

Current differential protection is the main protection of transmission lines including multi-circuit lines, whose sensitivity and reliability is mainly affected by the distributed capacitive current, especially with the widespread application of segment parallel transmission lines, the relationship of the electrostatic coupling between the circuits is more complicated, which makes the distributed capacitive current compensation more difficult. However, in the paper both the interphase capacitive current and the capacitive current between lines are compensated for the segment parallel transmission lines on the lumped parameter Π equivalent circuit model, and by using PSACD and Matlab simulation software, it has further study of the relationship between the differential current and the length of segment parallel lines for different voltage levels, and some suggestions of capacitive current compensation schemes are proposed for segment parallel transmission lines under different voltage levels.