基于正交坐标变换的永磁无刷直流电机转速估计方法

A Speed Estimation Method Based on the Orthogonal Coordinate Transformation for Permanent Magnet Brushless DC Motor Drives

为了实现方波永磁无刷直流电机无传感器技术中转速的实时估计,提出一种新颖的基于正交坐标变换的转速估计方法。在分析三相梯形反电势坐标变换原理的基础上,利用正交坐标变换重构出两实时保持正交关系的基波,并对其进行相应的解算,从而得到电机的转速信息。传统转速估计方法要以假设在相邻两次换相期间转速不变为前提,而该方法不基于这条假设,不受换相时刻的限制。最后,以一台表贴式方波永磁无刷直流电机为研究对象,进行了相应的实验,结果证明了该转速估计方案的正确性和可行性。

A new method was proposed in this paper for the permanent magnet brushless DC（PMBLDC） motor speed estimation in real time.Based on the orthogonal coordinate transformation,two orthogonal sine and cosine waves can be constructed from the trapezoidal back electromotive force（EMF）.It brings the opportunity for the rotation speed estimation.The proposed speed estimation method is not to be based on the assumed condition that the rotation speed does not change significantly over a certain period of time,which is necessary for the traditional speed calculation.Some experiments have been carried out on the prototype,which was the surface-mounted PMBLDC motor,and experimental results verified advantages of the proposed sensorless control method.