Selective‐tripping scheme for power supply arm on high‐speed railway based on correlation analysis between feeder current fault components in multisite

Abstract

Auto-transformer (AT) power traction networks with a parallel connection are the unique mode on high-speed electric railways in China. The up line and down line of power traction networks are connected at substation (SS), AT post (ATP) and sectioning post (SP) through busbars, circuit breakers and disconnectors. Currently, when a fault occurs on power traction networks, the feeder line protection devices at the up line and down line in SS trip simultaneously. After that, the nonfault line and instantaneous fault line recover by means of autoreclosing. This tripping mode enlarges the power supply-interrupted region. Based on the analysis of circuit networks of power traction networks on high-speed electric railways, the interrelations of currents in SS and ATP and in SS and SP are derived. When a fault occurs on one side of the power traction networks, the feeder currents in ATP and SP flow from the nonfault side to the fault side. The relation between feeder currents in SS and ATP and between feeder currents in SS and SP reflect this characteristic. A criterion for discriminating the fault side and selective-tripping scheme of breakers is proposed based on the correlation analysis of feeder current fault components in multisite. The simulation results show that this scheme can discriminate fault side and make a selective trip rapidly and correctly.

Fault Analysis of the Gautrain 2 × 25 kV AC Traction Power Supply System Using Disturbance Fault Records and On-Site Testing

“…The rails, the AEC and the BEC and other conductors that are at earth potential provide the path of the return currents and fault currents [30]. The types of faults that are found in a traction power supply systeminclude; catenaryto-earth (C-E Fault), feeder-to-earth fault (F-E Fault), feederto-catenary-to-earth fault (F-C-E Fault), feeder-to-catenary fault (F-C Fault), earth fault, and overcurrent fault [31]- [32].…”

Power supply arm protection scheme of high-speed railway based on wide-area current differential

“…When a metallic fault occurs near the installation station of the voltage transformer, especially near the ATS and SP, very low voltage leads to systematic error in the impedance angle and current direction, which may lead to misjudgment of the relay protection device. Reference [4] proposed a selective-tripping scheme of the power supply arm based on the calculation of the correlation coefficient of the feeder current. By analyzing the correlation coefficient characteristics of the feeder currents in all stations under typical short-circuit conditions, the fault identification and judgment can be realized, and the fault line can be isolated within 83 ms with selectivity and rapidity.…”