中文说明：
基于前馈补偿的PID控制算法。当闭环系统是连续系统时，使前馈环节与闭环系统的传递函数之积为1，可以大大提高系统的跟踪性能。
English Description：
PID control algorithm based on feedforward compensation. When the product of feedforward and closed-loop system is continuous, the performance of closed-loop system can be greatly improved