The Research Of Differential Protection Algorithm Based On Incremental Current

Current differential protection is one of the most important developed directions of line main protection. It has many virtues which other protections don't have. With the development of computer and communicate technology, and the drop of communicate equipment charge, the restrict of current differential protection on high voltage transmission line is little. The advantage of current differential protection is more important. With relay protection entering the microcomputer times, more research of current differential protection has new actual meanings. In fact, it becomes research hotspot again. This paper aims at the research direction; profound studies the current differential protection of two different principles and puts forward shunt current coefficient method, and validates different criterions.This paper first analyses the sensitivity and stability of full current protection and incremental current protection. Then it analyses the affect of load current and charge current between the two criterions on the line internal fault and external fault. Then it studies different criterions by shunt current coefficient method.At last, the RTDS (Real Time Digital Simulator) is used as the simulator of this protection system. The simulated power system is build up in RTDS PC terminal. The paper simulates the sensitivity and stability of full current protection and incremental current protection and the affect of load current. The result of simulation shows that the proposed criterion has the perfect perform of internal fault and external fault conditions and the correctness of...