旁路开关不停电代路运行的差动保护技术研究

由于光纤通道的飞速发展，光纤差动保护在电力系统的应用越来越广泛，目前220kV线路的两套主保护采用光纤差动保护。220kV线路两套均采用光纤差动保护后，当这些线路需要旁代时，在旁代的操作过程中，需要将两套差动保护退出，线路失去主保护，影响系统的安全运行，否则旁代过程中需导致停运线路，就失去了旁代线路的意义，故研究一种差动保护装置，在线路旁代过程中至少保留一套该种差动保护，不影响整条线路的正常运行。

Research of the differential protection technique to bypass circuit breaker substituting situation

Due to the fast developing of the fiber channel, the application of fiber differential protection is wider and wider. In the 220kV transmission lines recently, the two sets of main protection is fiber differential protection. After adopting the fiber differential protection in the 220kV lines, when the lines need substitution, in the substitution operation, it is necessary to withdraw two differential protection re- sults in the lines missing main protection, which influence the security of the system. Otherwise it need to outage the lines in the substitu- tion process which loss the meaning of the substitution lines. Thus it is important to research a differential protection device, which retain at least one differential protection in the line substitution process and not influence the normal operation of the whole line.