中文说明：
采用抗积分饱和PID控制算法进行离散系统阶跃响应。可以避免控制量长时间停留在饱和区，防止系统产生超调。
English Description：
The step response of discrete system is carried out by using PID control algorithm with anti integral saturation. It can avoid the control quantity staying in the saturation area for a long time and prevent the system from overshoot