基于逆变器资源控制特性的单端故障定位方法用于低频输电系统

Accurate fault location is crucial for power system emergency repair. However, the existing fault analysis-based fault location methods for the outgoing line of inverter-based resources use the traditional synchronous generator-based source model as the remote-end source model. The reliance on traditional source characteristics limits the adaptability of these methods in low-frequency transmission system (LFTS) used for offshore wind farm integration, where both ends of the system are inverter-based resources. Therefore, a novel fault location method is proposed for LFTS, which incorporates the source equations and fault network equations. Firstly, the source equations of LFTS are derived from control characteristics, while the network equations are derived from sequence networks and fault boundary conditions. Then, the fault location is converted into an optimization problem. The constraints of source equations, network equations and actual measured values are integrated in the objective functions, thereby allowing the fault distance and fault resistance to be identified by solving optimization problem. Finally, the performance of proposed fault location method is verified in PSCAD/EMTDC. The proposed fault location method exhibits an error of less than 1% in most cases, with a maximum error of less than 4%, and a fault resistance tolerability up to 300 Ω.