A Model Predictive Control Research For Dual Induction Motor Speed Control System Fed By Five-leg Inverter

Five-leg inverter is employed to feed dual induction motors independently for the cost-down of hardware circuits, it also can be used as the fault-tolerant operation for dual motor speed control system to improve the reliability of the system. In this paper, model predictive control is learn to make a deep research on the optimal control strategy for dual induction motor drive system fed by five-leg inverter, which can improve the speed performance of the motor drive system.The time delay is existed in the model predictive control strategy, which will cause the ripple of the system output value. To solve this problem, this paper proposes a time delay compensation two-step model predictive control strategy. An advanced step prediction is added to make compensation and eliminate the effect of the delay, reduce the ripple of the output value, and also can improve the steady state of the system.The large computation burden is existed by using the model predictive control strategy. In this paper, a restrained stated predictive control strategy for dual induction motor speed control system fed by five-leg inverter are proposed to solve this problem. By decreasing quantity of available switching states to reduce the computation burden, and the limit of switching action times during the transactions between switch states is involved in order to reduce power losses, and lower the system hardware requirement and hardware costs.In this paper, a15kW experimental prototype of five-leg inverter are been built, this prototype have the advantage of high efficiency, high power density and high reliability, which can be used for industrial prototype. The experimental platform of dual induction motor drive system are been made and the experiment of VVVF strategy and vector control strategy are been made. As a result, the control strategy is effective and the speed performance is well.