Author(s)

M. Miyatake, K. Matsuda & H. Haga

Abstract

The optimal operation of rail vehicle with on-board energy storage device minimizing total energy consumption is discussed in this paper. Until now, not enough research deals with the optimal control of the devices. The authors have developed the mathematical model based on a general optimization technique. In our study, the electric double layer capacitor (EDLC) is assumed as an energy storage device, because of its high power density etc. The proposed method can determine the optimal acceleration/deceleration and current commands at every sampling point under fixed conditions of transfer time and distance. The authors have also modified it for applying to catenary free operation. Using the proposed methods, simulations were implemented in some cases. The trend of optimal solutions such as values of control inputs and energy consumption is finally discussed. Keywords: power management, on-board energy storage, optimization, energysaving operation, supercapacitor, catenary free operation. 1 Introduction Electrical regenerative braking has reduced total energy consumption in electric railway systems. However, if the energy is not absorbed by another train, catenary voltage rises and regenerative failure is occurred under DC power feeding system. One of the way for absorbing regenerative energy is to use energy storage. Regenerative energy is stored in the energy storage and reused in the next acceleration. The energy storage decreases the loss of circuit resistance by compensating voltage drop. It also prevents regenerative failure even if substations cannot absorb energy. Energy saving effect as well as preventing regenerative failure is expected.

Keywords

power management, on-board energy storage, optimization, energysaving operation, supercapacitor, catenary free operation.