Position and Speed Measurement Method for Segmented Long Primary Double-Sided Linear Motor Based on Polynomial Fitting

To obtain the accurate motor position and speed feedback information, this paper presents a new position and speed measurement method of segmented long primary double-sided linear motor (SLP-DSLM). Considering that the SLP-DSLM has a double-sided long primary and dynamic secondary structure, a grating sensor based on laser array to measure the position is used in this paper firstly. Then, a new position acquisition method based on polynomial fitting is proposed in this paper. Finally, the adaptive tracking differentiator (TD) is introduced to obtain the velocity of secondary. Compared with the conventional position accumulation method, the hardware-in-the-loop experiment proves the effectiveness of the proposed method.