Reserche On Three-vector Model Predictive Dicrect Speed Control Considering Multiple Disturbances For Permanent Magnet Synchronous Motor

Model predictive direct speed control(MPDSC)uses a controller to simultaneously control the speed and current of the permanent magnet synchronous motor.This control structure makes it less setting parameters and good dynamic performance.However,the existing MPDSC only acts on one or two voltage vectors in one control cycle,and its steady-state performance still needs to be further improved.In addition,the realization of MPDSC is highly dependent on the motor model,and the motor model is changed due to internal disturbances caused by parameter changes,external disturbances such as load torque,and modeling errors during the motor operation,which adverse effects on control performance.In response to the above two problems,this paper first introduces the three-vector method to optimize three voltage vectors in one control cycle.Combining the calculated vector action time,the synthesized voltage vector amplitude and direction are variable,which can be more accurately track the ideal optimal vector,improving the control performance of the system.At the same time,in order to reduce the calculation amount of the three-vector method,this paper designs a direct voltage vector selection method.By the principle of deadbeat control,the mathematical model of the motor,the given value and actrual value of the motor current and speed,be adopted to calculate the optimal voltage vector directly,which can reduce the range of voltage vector combinations to be selected and simplify the optimization process.In addition,because the MPDSC adopts a non-cascaded control structure,the controller will be affected by multiple disturbances in the system.In response to this problem,this paper designs a Luenberger observer considering multiple disturbances to observe the disturbances in the system,and compensate the observed lumped disturbances to the motor model in real time.In order to prove the validity and correction of the three-vector model predictive direct speed control considering multiple disturbances for permanent magnet synchronous motor used in this paper,this paper verifies it in simulation and experiment respectively.Simulation and experimental results indicate that compared with the traditional model predictive direct speed control,the method in this paper improves the steady-state performance without increasing the calculation amount,and the overall performance of the switching frequency and the total harmonic distortion rate of the phase current is better.Compared with the method without considering multi-disturbance,the method in this paper shows better parameter robustness and anti-disturbance ability when the parameter changes and sudden load is added.