Analysis of High and Low Voltage Electromagnetic Ring Network's High Voltage Resistance of Transmission Line

The electromagnetic ring network is a special product in the development process of the power grid. When asymmetric faults, load rejection, protection failure, etc. occur in the ring network, overvoltage conditions will occur, which not only affects the stability of the system, but also affects important equipment in the power system. This article analyzes the capacitive effect, asymmetric faults, and the causes of over-voltage caused by load rejection in the long and unloaded lines in the ring network. Taking PSCAD/EMTDC to build 500kV-220kV-110kV ring networks with different voltage levels A1-A2 lines as an example, Analysis of the impact of high resistance operation on the suppression of frequency overvoltage and operating overvoltage, and aim at Various factors such as failures and protection failures have been simulated and studied. The research results have certain guiding significance for the operation of electromagnetic ring network.