Hybrid active damping for control of resonance in rail traction applications

Resonant interactions can occur between the traction supply and the power factor correction equipment on a locomotive. Passive resistive damping only offers a partial solution and results in large power consumption in the damping resistor. This paper proposes an alternative damping approach, which uses an active element to provide damping and control of resonance. This offers superior damping performance under all conditions and reduced power consumption. The concept is verified through simulation studies using parameters from existing locomotive systems, known to have resonance problems.