Decoupling Control of PMSM Deviation Based on Model Identification and Disturbance Observer

Permanent magnet synchronous motor is a strongly coupled and complex nonlinear system. In the actual operation of the motor, the current coupling between the d and q axis will affect the control accuracy of the current loop.In addition, the overall dynamic performance decreases when the inductance and load parameters change abruptly. In order to solve the problem that the control effect deteriorates when the inductance parameter changes due to traditional deviation decoupling. In this paper, the identification method based on Hankel matrix is used to obtain the mathematical modelof q axis current loop of permanent magnet synchronous motor in frequency domain. On this basis, the traditional deviation decoupling scheme is improved, and the theoretical PMSM first-order electrical model in the traditional deviation decoupling scheme is replaced by the identified mathematical model, so as to improve the decoupling effect. In addition, a disturbance observer is introduced into the bias decoupling structure, and the input voltage error caused by the change of inductance parameters and the current coupling is regarded as the disturbance, and then the observation and compensation are made to make up for the deficiency of the traditional bias decoupling. The experimental results show that the scheme has good dynamic performance and strong robustness, and greatly improves the decoupling performance of PMSM current loop.