Structure-variable sliding mode control of interior permanent magnet synchronous motor in electric vehicles with improved flux-weakening method

Bin Liu,Yue Zhao,Hui-Zhong Hu

doi:10.1177/1687814017704355

Abstract

A kind of flux-weakening control method based on speed loop structure-variable sliding mode controller is proposed for interior permanent magnet synchronous motor in electric vehicles. The method combines maximum torque per ampere with vector control strategy to control electric vehicle’s interior permanent magnet synchronous motor. During the flux-weakening control phase, the anti-windup integral controller is introduced into the current loop to prevent the current regulator from entering the saturated state. At the same time, in order to further improve the utilization rate of the direct current bus voltage and expand the flux-weakening regulating range, a space vector pulse-width modulation over-modulation unit is employed to contravariant the direct current bus voltage. Comparing with the conventional proportional–integral controller, the proposed sliding mode control algorithm shows that it has more reliable control performance. In addition, more prominent flux-weakening performance of the proposed flux-weakening method is illustrated by numerical simulation comparison.

Highlights

The interior permanent magnet synchronous motor (IPMSM) has been widely used in highperformance applications due to its advantages, such as small volume, high efficiency, as well as high power density.[1,2] In the electric vehicle driving system, the motor speed should closely follow a specified reference trajectory, regardless of any load disturbance, parameter variation, and model uncertainty
In the above-mentioned documents, IPMSM running performance below the base speed is not analyzed and the system instability resulted from the voltage saturation of current regulator and the d-q axis current coupling is neglected during FW control phase
When IPMSM runs above the base speed during FW control phase, the fluctuation of load torque and inductance parameters will influence the system stability and the FW properties

Summary

Introduction

The interior permanent magnet synchronous motor (IPMSM) has been widely used in highperformance applications due to its advantages, such as small volume, high efficiency, as well as high power density.[1,2] In the electric vehicle driving system, the motor speed should closely follow a specified reference trajectory, regardless of any load disturbance, parameter variation, and model uncertainty. In the above-mentioned documents, IPMSM running performance below the base speed is not analyzed and the system instability resulted from the voltage saturation of current regulator and the d-q axis current coupling is neglected during FW control phase.

Results

Conclusion