Analysis of the influence of train timetable on energy consumption on the metro line

Abstract

The latest technical solutions provide new opportunities for reducing energy consumption in electrified transport systems. The basic solution is to eliminate vehicles based on resistor start-up system and replace them with vehicles equipped with semiconductor based converter propulsion system (choppers and voltage source inverters). This type of drive also allows to recover energy (recuperation) from train braking, which is repeated very often case of metro lines. The problem is to find the receiver for this energy while the vehicle is braking. Large opportunities are also available when using various types of energy storage devices: stationary installed on the side of traction line and mobile ones used on-board the traction vehicles. Choosing the type of energy storage device for operating conditions, their capacity and the location of installation are complex optimization processes. This type of solution involves significant financial input, which reimbursement is spread over a long period of time. Therefore, it seems rational to seek solutions with limited financial outlay. This paper presents a solution analysis of adjusting the timetable and timeshifts between vehicle streams on the metro line to increase the efficiency of energy recovery of regenerative braking vehicles. This operation will reduce the amount of energy consumption by vehicles from the traction substations. The results presented in the paper were obtained by computer simulation of operation on the first line of the Warsaw subway, assuming that there was no energy storage devices and traction substations were operating without recuperation of the energy to the power system.