Study Of DTC System Of Motor Dynamic Load Based On DSPACE

The motor dynamic load system is theoretically and practically significant for the deep research of the structure, characteristics and parameter design of the traction drive system, as an important mean to the research of the transmission system of urban rail vehicles design, and also for the determination of matching character and optimization principle among traction converter, control strategy and traction motor.The motor dynamic load experimental scheme was proposed based on the systematic analysis of the load characteristics of the transmission system of urban rail vehicles, according to the direct torque control (DTC), whose structure, function and control strategies were thoroughly analyzed in the present study. The thesis proved the validity and feasibility of system mathematical model through stimulation.U-N model was used to improve the observation of the flux and at the same time the situation of torque ripple of DTC load system, for the problems like performance deficiency of flux observer and the bigger torque ripple in the system scheme through the stimulation analysis of the comparison among all the control strategies. The flux observer based on U-N model has stronger robustness for stator resistance deviation and speed disturbance. By introducing space vector modulation, the regulation process of torque would be smoother, which can decrease degree of torque ripple.The hardware was completed design of dynamic load experiment system and the real-time modification of stimulation model. The engineering prototype was made and debugged; the steady state characteristics and dynamic characteristics of the load system were also tested under different operating conditions. The experimental results show that the motor dynamic load experiment system in the present study can not only achieve the dynamic loading and dynamic load deducting under different operating conditions, but also response faster.