一种低载波比下内埋式永磁同步电机离散龙贝格观测器

摘要

为了实现低载波比下内埋式永磁同步电机 (IPMSM) 无位置传感器控制, 提出一种静止坐标系下离散域龙贝格观测器的设计方法.通过在静止坐标系建立基于扩展反电动势的离散域复矢量IPMSM模型, 得到给定电压和检测电流之间精确的数学关系, 并结合反电动势动态方程的精确离散形式构成全阶离散龙贝格观测器的数学模型.针对观测器包含虚轴极点的问题, 采用离散域直线平移法设计反馈增益矩阵, 保证观测器的稳定性和快速收敛性.在14kW永磁电机测试平台的实验结果验证该方法所设计的离散龙贝格观测器在低载波比条件下的可行性和有效性.%This paper proposes a design method of discrete-time Luenberger observer in the stationary coordinate system for position sensorless control of interior permanent magnet synchronous motor (IPMSM) drives.This method achieves a low pulse width modulation (PWM) to operating fundamental frequency ratio.Based on extended back-EMF in the stationary coordinate system, a discrete-time complex vector IPMSM model is established to describe the exact mathematical relationship between the applied voltage and the measured current.Consequently, combined with the dynamic characteristics of the back-EMF, a full-order Luenberger observer is constructed.Aiming to the problem that the observer contains pole point in the imaginary axis, a linear trajectory method in discrete domain is used for the design of feedback gain matrix.This method can guarantee the stability of the observer and allow fast convergence.The proposed discrete-time Luenberger observer was verified on the 14 kW IPMSM drive platform, and the experimental results demonstrated the feasibility and effectiveness of this observer in low-frequency-ratio.