Fault-location Scheme For Cross-coupling AT Feeding System Based On Fault State Matrix

After a fault occurs in the traction network,the quick and accurate fault location is very important for shortening power outage time and ensuring the safe and reliable operation of the electrified railway.At present,the fault location algorithm for cross-coupling AT feeding system is increasingly mature,and has great accuracy in engineering applications.However,due to the user’s need or the repairing equipment quits running,each circuit breaker may be opened and the operation conditions will be changed,which makes the traditional fault location method not fully applicable at this time.Therefore,the accurate fault location remains a challenge under different operation conditions and it is an urgent problem for reliable power supply of traction network to research on fault location methods under different power supply conditions.On the basis of studying the relationship between distribution of fault current and fault location algorithms of different operation conditions of traction network,this paper analyzes the mechanism of network topology affecting the current distribution,and a novel unified solution based on fault state matrix is proposed,which considers the organic unity of the operation conditions and distribution of fault current using fault state matrix.The adjacency matrix is used to form a switch state matrix reflecting topological structure of traction network,and distribution of fault current is mapped to current state matrix.The two matrix are unified to form a fault state matrix reflecting fault state of whole traction network,which obtains a practical generalized fault identified scheme and fault location algorithm.Moreover,a novel fault location algorithm called the generalized current ratio of parallel line is proposed.In addition,combining with the fault start principle and data processing method,a fault location scheme for different traction network structures is formed.Meanwhile,according to the characteristics of the high-speed railway,a simulation model of cross-coupling AT feeding system is established on the RTDS.A large number of simulation cases have verified the effectiveness of the proposed scheme.