Predictive control-based permanent magnet synchronous motor composite current control system and method

Abstract

The invention discloses a predictive control-based permanent magnet synchronous motor composite current control system and method. According to the system and method of the invention, the actual angular speed omega of a motor and the given reference rotational speed omegar of the motor, adopted as variables, are inputted to a PI rotational speed loop control module; the PI rotational speed loop control module calculates the difference of the actual angular speed and the reference rotational speed; by means of the proportional plus integral action of a rotational speed loop, the output currenti<*>q of the module is adopted as a q-axis reference current value; the three-phase output current of the motor is subjected to Clark transformation, the current of the motor in a two-phase stationaryalphabeta coordinate system is obtained, and the current is subjected to Park coordinate transformation, so that two-phase current under a dq rotating coordinate system is obtained; and reference current under a motor dq coordinate system and the two-phase current under the dq rotating coordinate system are inputted to a predictive current controller. According to the system and method of the invention, deadbeat predictive control and equivalent interference input are adopted. The current controller of the method can be applied to a PMSM torque or rotational speed driving system, has high current tracking performance and can quickly adjust the system when the system is subject to disturbance, so that the system will not be affected by a variety of disturbance factors.

Description

technical field [0001] The invention relates to the field of control technology, in particular to a compound current control system and method for a permanent magnet synchronous motor based on predictive control. Background technique [0002] Permanent magnet synchronous motors are widely used in electric vehicle drive systems due to their advantages of high efficiency, high power density and high reliability. [0003] The permanent magnet synchronous motor is a kind of multivariable, strongly coupled nonlinear system. Therefore, in the permanent magnet synchronous motor drive system, the vector control strategy according to the orientation of the rotor magnetic field is usually adopted to realize the control decoupling of the speed and current. The outer loop is The speed ring, the inner ring is the current ring. [0004] In practical applications, the control method based on PI is mostly used, and the speed and current tracking control of the motor are realized by adjusti...

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Problems solved by technology

[0006] However, the design of the deadbeat predictive controller relies on the mathematical model of the motor. When there are disturbances such as parameter changes in the system, the control performance of the system will be severely degraded, and accurate current tracking control cannot be achieved, which limits its application in the electric drive system. application

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