Current loop delay compensation method for three-phase permanent magnet synchronous motor driving system

Abstract

The invention discloses a current loop delay compensation method for a three-phase permanent magnet synchronous motor driving system. The method comprises steps that a d-q axis stator current of a next period based on a motor model is predicted, and the d-q axis stator current is taken as a PI regulator feedback value for calculation to obtain a stator voltage reference value; aiming at the influence of motor parameter change on prediction precision, the prediction model is further corrected, when actual parameters are inconsistent with motor parameter nominal values, an error voltage item inthe model plays a role in correcting a current prediction value. The method is advantaged in that hardware configuration does not need to be changed or extra logic devices do not need to be added, themethod is simple in operation, low in cost, simple to implement and easy to expand, weakens the limitation of digital delay on the adjustment speed of the current loop, accelerates the current tracking characteristic, still ensures higher control precision even under the condition of larger motor parameter change, and is suitable for permanent magnet synchronous motor driving occasions with higher requirements on dynamic tracking and control precision.

Description

technical field [0001] The invention relates to the field of motor control technology, in particular to a method for compensating a current loop time delay of a three-phase permanent magnet synchronous motor drive system. Background technique [0002] Permanent magnet synchronous motor (PMSM) can achieve high precision, high dynamic performance and wide range of speed regulation, so it is used in many motor drive occasions. Rotor Field Oriented Control (FOC) is currently the most widely used motor control strategy in PMSM systems. Compared with other strategies, it has the advantage of high torque control accuracy. The rotor field oriented control adopts a cascade control structure, and the current loop is used as the inner loop of the system. Its excellent tracking characteristics and high enough bandwidth are the prerequisites to ensure the stability and fast response of the system. Without considering the d, q axis current coupling, the PMSM current loop bandwidth is rel...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a current loop delay compensation method of a three-phase permanent magnet synchronous motor drive system for the defects involved in the background technology, so as to solve the problem that the response speed of the current loop of the permanent magnet synchronous motor drive system is affected by the digital Large delay constraints, the current tracking characteristics of traditional compensation schemes are greatly affected by changes in motor parameters, traditional current loops need to change hardware configuration or increase hardware costs and other technical problems

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