New Reference Frame for Position Sensorless Controls of Permanent Magnet Synchronous Motors

针对高性能永磁同步电机驱动系统，研究了基于最大力矩控制坐标系的无位置传感器控制。研究结果如下：1.无位置传感器控制系统的续航里程扩展(1)提出了一种新的用于无速度传感器控制的电机模型，以扩展包括稳态和低速在内的行驶范围。(2)将基于最大力矩控制坐标系的信号注入方法应用于扩展电动势法的位置估计。(3)在最大力矩控制框架的f轴上，通过信号注入实现了无转矩脉动的位置估计。参数变化与信号注入条件的关系(1)对温度变化和磁饱和引起的电机参数误差估计误差进行了解析计算，并解释了误差的特点。(2)通过在最大力矩控制坐标系的f轴上注入电流信号来抑制位置估计误差。(3)几百赫兹等低频信号提高了位置估计增益。(4)低频信号能有效地降低由于信号电流引起的噪声水平，目前还没有对速度控制和电流控制的性能进行评估。

Position sensorless controls based on a new reference frame, which is called “maximum torque control reference frame”, were studied for high-performance drives of permanent magnet synchronous motors. The results were as follows,1. Driving range extension of sensorless controls(1) A new motor model for sensorless control was derived to extend the driving range including steady state and low-speeds. (2) Signal injection using the maximum torque control reference frame was applied to the position estimation with extended electromotive force methods. (3) The position estimation was realized by signal injection without torque ripples in f-axis of the maximum torque control frame.2. Relation between parameter variation and the condition of signal injections(1) Estimation errors caused by motor parameter errors due to temperature changes and magnetic saturations were calculated analytically and the characteristics of the errors were explained. (2) The position estimation errors were supressed by injecting current signals in the f-axis of the maximum torque control reference frame. (3) Position estimation gain was improved by lower frequency signals such as a few hundred hertz. (4) The lower frequency signals were effective in decreasing sound level of noise due to signal currents.Evaluations of the performance of speed control and current control have not attained yet.