New Achievements in the Rotor Field-Oriented Control for Autonomous Locomotives : Part 2: Control Implementation and Experimental Performances at Low Speed

The paper is dedicated to the experimental determination of the performances of the traction system of an autonomous electric locomotive. The traction system is composed by the voltage inverter and induction motors and its control is based on the indirect rotor field-oriented control (IFOC) method. For this particular application, the IFOC implementation has some major difficulties. First, the motors’ voltage cannot be used for vector field identification because it is strong distorted. On the other part, the control structure contains four controllers distributed on the two interconnected control ways and their tuning is very complicate. In order to mitigate these difficulties, the authors have developed a modified structure by using two hysteresis current controllers. Next, the control algorithm has been developed and implemented on the dSPACE 1104 DSP board. In order to test the entire system, a dedicated experimental stand that uses the recovery of the mechanical energy of the motor was used. The experimental evaluation was performed to determine the dynamic and static performances over entire speed domain.