Predictive direct duty cycle control method for permanent magnet synchronous motor based on variable control-set

Abstract

The invention discloses a predictive direct duty cycle control method for a permanent magnet synchronous motor based on a variable control-set. The method comprises the steps of computing a voltage vector of a stator at a previous control moment, wherein the computation adopts a new vector synthesis mechanism; collecting three-phase current values of the motor stator, and estimating a flux linkageamplitude and an electromagnetic torque value of the motor stator at a current control moment; collecting a rotation speed of the motor and an electrical degree of a rotor at the current control moment; computing effect intensities of three-phase basic voltage vectors on the flux linkage amplitude and the electromagnetic torque value; building a three-phase duty cycle robust prediction model; dividing the three-phase basic voltage vectors into a strong level, a middle level and a weak level for electromagnetic torque value and flux linkage amplitude controller intensities; separately buildinga torque variable control-set and a flux linkage variable control-set; selecting 11 basic duty cycle combinations; determining the optimal basic duty cycle combination; and determining optimal three-phase duty cycles. According to the method provided by the invention, the excellent torque dynamic control performance of the prior art is kept, and the five-part type or seven-part type voltage vector control motor is not needed to be output without the assistance of a modulator.

Description

technical field [0001] The invention belongs to the technical field of permanent magnet synchronous motor control, and more specifically relates to a method for directly predicting duty ratio control of permanent magnet synchronous motors based on variable control sets. Background technique [0002] Permanent magnet synchronous motor (Permanent magnet synchronous motor, PMSM) has the advantages of simple structure, high power factor, wide speed range, etc., and has been widely used in the fields of numerical control machine tools, elevator control and traction drive. In recent years, Finite Control-Set Predictive Torque Control (FCS-PTC), as a kind of closed-loop control method using online optimization, can significantly improve the torque dynamic performance of the motor, and has achieved great success in the field of PMSM drive. successfully applied. [0003] When FCS-PTC is used to control the PMSM drive system (Two-level Voltage Source Inverter fed PMSMs Drive System, ...

AI Technical Summary

Problems solved by technology

At present, this type of method outputs a three-stage virtual vector (V 0 -V 1 -V 0 ) research work has achieved good results, and output five-stage (V 0 -V 1 -V 2 -V 1 -V 0 ), and even seven-segment (V 0 -V 1 -V 2 -V 7 -V 2 -V 1 -V 0 ) The extended control set PTC of the virtual vector still needs to assist the SVPWM modulation technology, which increases the complexity of the method

[0007] In the traditional improvement method, the continuous control set PTC needs to use the precise motor parameters, which reduces the parameter adaptability of the control method; the multi-vector PTC and the extended control set PTC need the assistance of the modulator to output the voltage space vector to control the motor, which increases the The complexity of the control method

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