Dynamic performance of an induction motor driven trolleybus

This paper deals with the electromechanical dynamic performance of a trolleybus, whose electrical traction system is based on a voltage source inverter fed motor. The voltage source outputs the combined variable-AC-voltage and variable-frequency required by the different vehicle´s control modes. The street DC catenary serves as a DC voltage source for the inverter. The authors depart from a brief presentation of the basic mathematical relations that lead to the different trolleybus modes of control. Different pulse control functions for the invertor leads to different speed and torque controls for the trolleybus motion requirements. The paper includes an extensive number of time domain oscillograms, whose variables serve to explain the trolleybus powering and braking modes of operation