Brushless doubly-fed machine torque ripple minimization control device and control method thereof

Abstract

The invention discloses a brushless doubly-fed machine torque ripple minimization control device and a control method thereof. In view of the problems of large torque and flux ripple and unfixed switching frequency of a brushless doubly-fed machine in the traditional direct torque control method, on the basis of analysis of the cause of ripple generated in the traditional direct torque control, the torque and flux at next time are predicted using the idea of predictive control according to the state equation of a brushless doubly-fed machine and the current, torque and flux at the current time, the action time of a non-zero voltage vector is calculated using the principle of minimum torque ripple in one control period, and thus, the torque ripple is reduced. Compared with the traditional direct torque control method, the control method reduces the torque ripple to the maximum extent, quick response and simple control of the traditional direct torque control method are maintained, and the control performance of the system is improved.

Description

technical field [0001] The invention relates to the technical field of motor control, in particular to a control device for minimizing torque ripple of a brushless doubly-fed motor and a control method thereof. Background technique [0002] Brushless Doubly-Fed Machines (BDFM) consists of two sets of independent stator windings (power windings and control windings) and a rotor with a special structure, with simple structure, brushless, reliable operation, and the required frequency converter Features such as small device capacity. Direct Torque Control (DTC) has the advantages of simple control structure, fast torque dynamic response, strong robustness, and little dependence on motor parameters. Sensitivity to changes etc. The traditional DTC uses a double hysteresis loop controller to control the torque and flux linkage separately, and only one voltage vector acts in each sampling cycle, which cannot fully compensate the torque and flux linkage errors, resulting in torque...

AI Technical Summary

Problems solved by technology

The SVM-DTC algorithm proposed in the prior art can effectively reduce the torque ripple, but it requires a large amount of calculation and requires more motor parameters; the discrete space vector (DSVM) modulation method proposed in the prior art maintains the traditional direct Torque control has the advantage of good robustness, but the improvement of control accuracy is based on the premise of subdividing the voltage vector, which increases the complexity of the control system; the use of fuzzy control algorithm has good dynamic performance, effectively reducing the torque pulse, However, the determination of the membership degree of each variable in the state machine has certain uncertainties. If the membership degree is not selected properly, the performance of the system will deteriorate; the improved fuzzy DSVM-DTC control strategy is adopted, although the torque and speed ripple control are improved. effect, but the fuzzy controller uses 5 input quantities, and the fuzzy control rules are more complicated

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