Rotor Field Quasi-Oriented Control Algorithm Implementation for Railway Traction Systems on dSPACE DS1103

The aim of this paper is the experimental implementation and validation of a rotor field quasi-oriented control algorithm for a railway vehicle traction system. The implementation was done for a dSPACE DS1103 prototyping board in the Matlab Simulink environment. The control system assumes that the current system is oriented by the rotor flux and that the real flux follows the imposed value. This way the estimation of the rotor flux is not necessary making the control algorithm suitable for low cost industrial DSP applications. The drawback is given by the fact that the current projections on the dq axes cannot be regulated directly, but only by means of the current phasor magnitude. The proposed control system proved good results, in terms of current and speed regulation especially at variable mechanical load (such as track joints or switches), both in static and dynamic regimes, but some precautions must be taken at null imposed speed as the minimum frequency of the magnetizing current leads to a slow rotation of the idle motor.