一种基于线电感变化特征的永磁同步电机转子初始位置检测新方法

A Novel Initial Rotor Position Estimation Method for PMSM Based on Variation Behavior of Line Inductances

具有转子凸极结构的永磁同步电机中受转子凸极效应的影响,绕组的自感和互感随转子位置呈现近似正弦的周期变化,以此为基础,提出了一种基于线电感变化特征的永磁同步电机转子初始位置检测。首先,通过注入高频低压脉冲来进行线电感辨识,并深入分析了绕组电流对线电感辨识的影响,同时利用傅里叶级数分解得到线电感变化曲线;随后建立了角度-线电感关系的数学模型,并采用旋转坐标变换计算转子初始位置角,但是该方法无法判断转子磁极的极性,因此在初步辨识出转子位置角的基础上,向电机施加等宽电压脉冲,利用磁场饱和引起的响应电流幅值的变化来估计出转子的磁极极性;最后实验结果表明,该方法能够准确、有效地估计转子初始位置。

In permanent magnet synchronous motors （PMSM） with a saliency pole structured rotor influenced by saliency effects, the self-inductance and mutual-inductance present periodicity sinusoidal variation, Starting from this feature, a novel initial rotor position estimation method based on variation behavior of line inductances is presented in this paper. The line inductance can be estimated by injecting high frequency low voltage pulses, and the influence of winding current to line inductance are analyzed firstly, the line inductance ripples curve is fitted and obtained using Fourier series secondly, then the position vs. inductance characteristics are modeled for estimating the rotor position using rotational coordinate transformation. While this method can not recognize the direction of rotor flux, so the identical width voltage pulses are applied to the motor armatures and then the direction of rotor flux is achieved. The experimental results show that the proposed method estimates the initial rotor position reliably and efficiently.