Intelligent Online Monitoring and Diagnosis of a DC Superconducting Current Limiters

Flexible DC transmission can realize the connection of new energy networks and DC grids, which is a key technology for building the future intelligent transmission network. In order to ensure the normal operation of the flexible DC transmission system, a DC superconducting fault current limiter is used to limit the current of the circuit. However, the structure and operating conditions of DC superconducting fault current limiters are complex; at the same time, their fault characteristics are nonlinear and dynamic coupling, and there is a problem of highly overlapping features between some fault modes, which brings a lot of problems to identify and locate faults. The purpose of this article is to realize the online monitoring and fault diagnosis of DC superconducting fault current limiter, and propose a multi-source information fusion based DC superconducting fault current limiter hierarchical protection method. Aiming at the problem that the fault of the DC superconducting fault current limiter is difficult to identify and locate, a fault diagnosis method of BP neural network is proposed.