A Traction and Auxiliary System Suitable for Urban Rail Transit Train Passing through the Third-rail Outrage Zone

Objective When a traditional third-rail power collection rail transit train passing through outrage zones, the high-voltage busbar may lead to unintended electrification of the zone, posing safety risks. Therefore, it is necessary to design a new type of traction and auxiliary system to mitigate the risk of high-voltage busbar unintended electrification in third-rail outrage zones, while improving auxiliary system availability and reducing vehicle configuration costs.

Method A new traction and auxiliary system scheme is proposed, in which the high-voltage busbar in traditional design is eliminated to avoid the risk of unintended electrification in third-rail outrage zones. A current sensor for track gap detection is used to identify the third-rail outrage zone. When the train enters the outrage zone, the traction motor functions as a generator to convert kinetic energy into electrical energy, which is supplied via a feeder line to the auxiliary inverter. This resolves the problem of the auxiliary inverter failing to operate normally when the train passes through an outrage zone.

Result & Conclusion The new traction and auxiliary system scheme can be implemented through simple modifications to the traditional circuits of the train. By eliminating the high-voltage busbar, the safety risk of unintended electrification in third-rail outrage zones is completely eradicated, ensuring the safety of operation and maintenance personnel. Meanwhile, the auxiliary inverter can continue to operate normally in outrage zones, avoiding system shutdowns caused by power interruptions in traditional schemes, enhancing the availability of the auxiliary system and reducing vehicle configuration costs.