Locomotives

Simple Rectifier Control System

ATS provides a simple rectifier control system for the Railserve LEAF (Low Emission And Fuel) Locomotive.

A simple rectifier consisting of diodes is used to rectify the incoming 480V supply to produce a distributed DC bus of 650V.

Highlights

  • The rectifier causes some voltage distortion on the 480V bus but the impact will be substantially less at low speeds. This is because the current drawn from the rectifier at low speeds is a fraction of the traction motor currents. Also, the power factor of the rectifier is consistently high.
  • The rectifier blocks reverse current flow which does not allow regeneration into the AC bus. This means that power recovered from traction motors used for braking must be dissipated in dynamic brake resistors or used by other traction motors on the same car.
  • This is a simple system and the total cost is minimized. The rectifier harmonics are unlikely to be a problem if the maximum traction power in kW is less than 50% of the total kVA of generating capacity on the AC bus.