1. Rail Traction Power: A Growing, Fragmented, High-Stakes System Urban rail and high-speed rail have both grown into dense, highly interdependent systems. From metro stations and tunnels to high-speed stations, lineside cabinets and onboard auxiliary systems, “having power” is no longer sufficient. Operators are now expected to guarantee: Stable, high-quality power despite regenerative braking and fluctuating traction loads High electromagnetic compatibility (EMC) in harsh