Simulation of Train Dynamics in Subway System

Nowadays computer technology provides different ways to check technical and economical study of DC traction supply systems projects. It is quite possible to simulate the rolling stock transportation based on operation program, also voltage and current calculation and determines the rectifiers and inverters outputs in every moment and position and also it is possible to check the rectifier substation proposed positions.The estimated passenger number, operation program and passenger comfort are necessary parameters in rolling stock selection. It is possible to determine rectifier output in normal and one transformer rectifier unit out of service condition. As well calculation provides the information of energy consumption and rail voltage regarding the earth.Rolling stock data is needed for calculation and simulation. As an example it is necessary to know motor specification at motoring and braking condition, its weight and also track data such as gradient, curve and maximum speed. All contact line, current returning circuit, substation place and operation program data must be defined.The first step to simulate traction supply network is simulating the train dynamic movement in order to specify the position, speed, acceleration and rolling stock power consumption. Therefore this topic was chosen for the present research.In this paper the dynamic train dynamics was taken into account. The train dynamics graph was presented as a key curve in determination of the number of existent trains in return lines and by the simulation process, the moment rates of mechanical parameters such as the location, the consumption rate of trains in each point of the line and the moment velocity of the return trains are presented.