Return current management-operational and safety aspects of AC & DC traction systems

Conventional ac traction power is a Single Wire Earth Return (SWER) System, This places challenge on, containment of the touch potential of the rail. As traction powers increase, return current management which is closely related to the earthing and bonding practice, becomes an important factor to be considered in the economics & safety of traction power supply-under which billions of kilo metres of freight and passenger movement is logged. Further, need of structure and platform earthing is emerging as a major challenge to guarantee safety to the users, with steadily increasing transformation capacity in traction sub-stations. Similarly, dc traction systems pose an entirely different set of challenges to the adjoining non-railway installations. The presentation aims to flag the issues and provide Indian Railways’ experience and global practices.