Novel analysis methodology of differential protection operation behavior Part one Principle

作者：Lin Xiangning^*; Liu Pei; Xu Tao

来源：Automation of Electric Power Systems, 2003, 27(23): 45-50.

• Current transformer
• Differential protection
• Product restraint
• Through current
• Transferring ratio

A novel analysis methodology aiming at evaluating the operating behavior of a variety of differential protection criteria is proposed. The evaluation of the criteria proceeds with a plane in which the through current and current transformer transferring ratio (or the ratio of outgoing current to incoming current) as its coordinate axis. By use of this method, the mal-operation area of any differential protection criteria is visualized when current transformer saturates due to the large through current induced by external fault. On the other hand, the possibility of fail-to-trip of the criteria can be evaluated as well when outgoing current exists in the occasion of any internal fault. Therefore, it is possible to adjust individual settings in the percentage differential characteristics rationally and thus highlight the advantages of the certain criterion furthest.

• 出版日期2003