Alternating Current Asynchronous Motor Control System based on Vector Control

Abstract

Alternating current asynchronous motor has the advantages of simple structure, reliable operation, and low cost. It is especially suitable for the wheel drive system of large electric drive dump truck, and the nonlinear characteristics put forward higher requirements for the control system. According to the operation characteristics of a vehicle AC asynchronous motor, the characteristic parameter description equation was obtained. Based on the principle of vector control, the control system was designed, the analysis model of the control system was built based on Simulink, and the model speed and torque control were verified. The single and double step speed, slow acceleration and load operation was selected to test, and the changes of speed, output torque and other parameters were obtained. With reference to the actual vehicle characteristics, the test bench of asynchronous AC motor control system was built, and the characteristics of the control system under different load conditions were selected for verification. The analysis results show that the motor runs well in the control system built by vector control. Under different operating conditions, the system responds quickly, the parameter fluctuation is small, and the overall stability is maintained. Under the action of the control system, when operating below the fundamental frequency, the constant speed regulation operation is realized through voltage compensation. When the fundamental frequency is exceeded and the load condition is met, the system realizes constant power speed regulation. The maximum efficiency of the motor is more than 90%, which increases with the increase of load. The control system makes the motor show good advantages. It shows the reliability of the control model and provides a reference for this kind of design research.