Simulation model of AC/DC traction converters and drives for the calculation of input power characteristics

The authors present a model for the simulation of AC/DC thyristor controlled traction vehicles. A FORTRAN program for the simulation of such a vehicle is developed. It is based on a modern numerical methods library and runs on a mainframe computer. Efficiency of Runge-Kutte Adams and Gears integration methods are compared. The Adams variable stage, variable order predictor corrector method proves to be the most efficient, although Gears method is shown to be insensitive to the circuit stiffness. A simple closed loop control circuit is applied to reach a desired steady state as quickly as possible and a new quasi steady state is reached usually in less than ten line voltage periods