改进的广义预测算法在过热气温控制中的应用

Implicit Generalized Predictive Control Algorithm Based on Soft Coefficient Matrix and Its Application

针对传统广义预测控制算法(GPC)的计算量大这一缺陷,结合隐式广义预测算法(IGPC)和基于柔化矩阵的广义预测算法,通过辨识参数和输入增量引入柔化系数矩阵进行约束的方法对原算法进行改进,算法只精确计算当前时刻的控制作用而对未来时刻的控制序列进行离线近似计算。该算法简单,不必求解丢番图(Diophantine)方程和矩阵求逆,减小了在线计算量,确保了系统的快速性,并能够将输入很好地控制在约束范围之内,并具有良好的控制性能。同时隐式广义预测算法对模型的阶次、参数的变化都有较好的鲁棒性,能适应电厂过热汽温的控制。

To avoid large amounts of computation of the traditional generalized predictive control algorithm,a fast algorithm of GPC based on implicit generalized predictive control and the soft coefficient matrix is presented by exactly computing the current control action and approximately computing the future control sequence off line.The algorithm is simpler and doses not need solving the Diophantine equation and the inverse matrix so that the on-line computation burden is strongly re- duced and responding speed of the system is increased,it can limit the inputs within the range of constraints required.The simulation results show that the proposed algorithm is practicable and effective.Meanwhile,implicit generalized predictive control has the characteristic of robustness when the order and parameter of the modet have changed,so it can be suitable for the superheated steam temperature of boiler superheated system.