Traction motor test bench

The bench is designed for post-repair acceptance testing of DC and pulsating-current traction motors used on mainline electric locomotives. It checks motor operation at no load and under load, measures rotational speed, currents and voltages, winding and bearing temperatures, and monitors commutation and vibration. Results are recorded automatically and compiled into a test report.

Load tests are performed using the back-to-back method: two motors are coupled shaft to shaft, one runs as a motor and the other as a generator, and the generated energy is returned to the power circuit. Only the losses are drawn from the mains, so the rating of the supply input is several times lower than the combined power of the machines under test. Armature circuits and field windings are fed from regulated rectifier units with smooth voltage and current adjustment.

The bench comprises a foundation frame with mounting plates and clamps for the motor feet, a coupling, a power cabinet with rectifiers and switchgear, a control cabinet with an industrial controller and operator panel, and a set of sensors. On request the bench is extended with a high-voltage insulation test unit, a vibration measurement channel, forced motor ventilation and a workstation that exports test reports to the depot network.