Research and application of bypass replacement logic and risk control of stability control device

In order to prevent the power failure of the whole line caused by the maintenance of line switch, bypass switch is set in 220kV Main Wiring of some power plants. When the bypass replaces a line, there are three states in turn: line, bypass and line parallel operation, bypass operation. The bypass replacement logic of stability control device needs to correctly distinguish and switch these three states. This paper deeply studies the variation law of bypass, line analog and switching value in the whole bypass replacement process, puts forward the correct switching judgment method of line outage, trip and overload criteria, as well as the operation risk and prevention and control measures of bypass platen in the bypass replacement process, and then takes a power plant stability control device as an example to verify the results, which shows that the bypass replacement logic proposed in this paper is feasible. Risk prevention and control measures can ensure the correctness of logical discrimination of stability control devices in the process of bypass replacement, and can be extended to other power plant stability control devices.