Then the position errors of linear motors on closed loop control are analysed and measured, the table of the positioning errors is established, and the compensatory function of PMAC is used to carry out real-time compensation for position errors of linear motors. 分析并测定直线电机在闭环控制下的定位误差,建立误差补偿表,利用PMAC的误差补偿功能对直线电机的定位误差进行实时的软件补偿。