What is circuit breaker failure protection? In fact, circuit breaker failure protection refers to the use of the protection action information of the faulty electrical equipment and the current information of the rejected circuit breaker to distinguish the failure of the circuit breaker when the relay protection action sends a tripping command and the circuit breaker refuses to operate. It can cut off other related circuit breakers in the same station in a short time, limiting the power outage range to the minimum, thereby ensuring the stable operation of the entire power grid and avoiding the occurrence of generators Severe burning of faulty components such as transformers and the collapse and collapse of the power grid

In power plants and substations with voltage levels of 110kV and above, when a short circuit occurs in the transmission line, transformer, or busbar, and the protective device acts to remove the fault, the circuit breaker of the faulty component may refuse to operate, which means that the circuit breaker failure occurs. The reasons for circuit breaker failure are multifaceted, such as the short circuit of the circuit breaker tripping coil, and the failure of the circuit breaker operating mechanism. The circuit breakers and protective devices of the high-voltage power grid should have a certain backup function, so that they can still effectively cut off faults in the event of circuit breaker or protective device failure. The remote backup protection scheme for adjacent components is the simplest and most reasonable backup method, which is not only a backup for protection data, but also a backup for circuit breaker rejection. However, in high-voltage power grids, due to the auxiliary effect of each power supply branch, it is often difficult to achieve the above backup methods (insufficient sensitivity), and due to the long action time, it is easy to expand the scope of accidents, and even cause system instability and collapse. In view of this, for important 220kV and above main lines in the central area of the power grid, when system stability requires the installation of full line quick action protection, two independent sets of full line quick action main protection (i.e. double protection) can usually be decorated to prevent the rejection of protection devices; For the rejection of circuit breakers, special circuit breaker failure protection is installed