PID控制本身是一种基于对“过去”、“现在”和“未来”信息估计的简单但却有效的控制算法。由于其算法简单、鲁棒性能好、可靠性高等优点，PID控制策略被广泛应用于工业过程控制中。-PID control itself is based on the " past" , " now"　and " future"　information to estimate a simple but effective control algorithm. Because of its algorithm is simple, robust performance, high reliability, PID control strategy is widely used in industrial process control.