Unweighted Predictive Torque Control Method for Permanent Magnet Motor System Based on Discrete Duty Cycle

Abstract

The invention discloses a permanent magnet motor system no-weight prediction torque control method based on a discrete duty ratio. The method designs a brand-new method for combining an alternative vector by combining with the discrete duty ratio. Two adjacent effective vectors and a zero vector are selected to combine the alternative vector, and meanwhile, duty ratio information corresponding tothe alternative vector is directly generated. On the basis, an extended control set is constructed so as to improve control accuracy for the torque and a flux linkage. By use of the method, screeningis directly carried out in an inverted-triangle matrix regions corresponding to a target vector set, so that the prediction process of an optimal vector and a duty ratio calculation process are combined into one, the integral efficiency of the algorithm is improved, and the control accuracy for the torque and the flux linkage is improved.

Description

technical field [0001] The invention relates to the field of permanent magnet synchronous motor control, in particular to the field of motor control that takes into account the running performance of the motor under the condition of a predictive torque control strategy, and in particular relates to a weightless permanent magnet motor system based on discrete duty ratios Predictive torque control method. Background technique [0002] Permanent magnet synchronous motors have the advantages of simple structure, high torque output capability, high power factor, etc., and are widely used in electric vehicles, rail transit, aerospace and many other industrial fields. In recent years, with the rapid development of power electronic technology and microprocessors, model predictive control algorithms have been gradually applied to power electronic control and motor control and other fields. [0003] At present, for the permanent magnet synchronous motor drive system fed by the voltag...

AI Technical Summary

Problems solved by technology

The traditional finite control set model predictive torque control strategy has a simple structure, fast dynamic response, and strong system robustness, but the control accuracy of torque and flux linkage is limited, mainly because the traditional control set only contains 8 alternatives Vector, specifically 6 effective vectors with fixed amplitude and phase angle and 2 zero vectors, so that the control accuracy of flux linkage and torque is limited

In addition, the value function of the traditional finite control set model prediction torque control strategy includes the error of the two output quantities of torque and flux linkage. Due to the different dimensions of torque and flux linkage, it is difficult for the value function to balance the performance of torque and flux linkage prediction. The degree of deviation between the value and the expected value. To this end, a weight coefficient needs to be added to the flux item of the value function

The value of the weight coefficient is related to the control effect. If the weight coefficient is not selected properly, it will lead to a decrease in the control accuracy of the control system.

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