永磁同步电机精确瞬时速度检测

Precise Instantaneous Speed Detection for Permanent Magnet Synchronous Motors

提出了一种利用低分辨率光电编码器实现高精度的永磁同步电机瞬时速度检测方法。首先,根据永磁同步电机运动模型建立瞬时速度观测器,对电机的瞬时速度和扰动转矩进行估计;再根据电机的不同运行速度,对编码器位置信号进行同步或异步采样,获得电机转子的准确位置;然后利用位置检测值对瞬时速度观测器的估计值进行校正。为了降低负载惯量变化对速度观测器的影响,利用电机瞬时速度和扰动转矩的估计值对负载惯量进行自动辨识,并根据辨识结果对瞬时速度观测器的参数进行在线调整。与传统速度观测器相比,该方法减小了位置检测误差和滞后时间,提高了瞬时速度检测精度,尤其是当电机低速运行时,速度检测精度得到明显改善。

This paper introduces a novel instantaneous speed detection method for permanent magnet synchronous motors（PMSMs）.High detection precision is achieved by using a low resolution encoder.First,instantaneous speed and disturbance torque are estimated by a Luenberger observer based on the motion model of PMSM.Then,the estimation errors are corrected by angular position,which is obtained by synchronous sampling method（SSM） or asynchronous sampling method（ASM） according to different speed.Furthermore,in order to reduce the influence of load variation on instantaneous speed observer,load inertia is identified using the estimated values of speed and disturbance torque,and then the parameters of speed observer are adjusted according to load inertia.Compared with traditional speed observer,the method mentioned above eliminates the position detection error and delay time.So detection precision of instantaneous speed is improved largely especially in low speed region.