The Braking Technique and Control Method for Increasing Regenerative Energy in DC Electric Railways

Abstract

In DC electric railway systems, energy-saving can be expected by using regenerative brake. However, since the regenerative brake force decreases at high-speed range, the use of a mechanical brake to obtain a constant brake force results in losses and reduces the energy-saving effect. The “regenerative brake notch”, brake method proposed in a previous study, suggests a way of informing the brake start point for stopping only with the regenerative brake force. However, when this method is applied to an actual train running, it is not always possible to stop at the stopping position due to disturbances such as the running resistance and the gradient of railways. In this study, we proposed a driver advisory system and a control method to solve this problem. We verified the responsivity of this control method in actual motors drive system and the energy-saving effects on applying the proposed method by using a numerical simulation assuming of an actual railway running.