Technical Efforts for Energy-Saving Operation of Linear Metros in Japan

This paper reply reports the newest technical challenge of energy-saving automatic train operation (ATO) in a Japanese linear metro from 2016 through 2018. Based on the fundamental energy-saving strategy established in the eco-rail project by Japan Subway Association (JSA) from 2013 through 2016 in which possibly long coasting and power-limiting regenerative braking scheme, the authors proposed design of the energy-saving running profile with longer coasting by enhancing powering acceleration and evaluated the energy-saving performance through numerical calculations as well as on-track vehicle tests on a commercial linear metro line in Osaka-City. The reduction of the total traction-energy of six percent in total was confirmed in spite of the worse powering energy loss of linear induction motors according to larger slip frequency for the powering acceleration enhancement.