Assessment of grounding schemes on rail potential and stray currents in a DC transit system

This paper studies the effects of different grounding strategies, including ungrounded, solidly grounded, and diode grounded on rail potential and stray currents in the Taipei Rail Transit Systems (TRTS). The TRTS is a dc transit railway and the running rails are used as the return conductor for traction currents. The advantage is that no dedicated return conductor is required while the disadvantages are rail potential and stray current problems. Thus, the analysis of grounding strategies is important and necessary. Sample simulation results for the red line between Tamshui (R33) and Chuwei (R31) stations are presented.