动态矩阵控制的截断误差校正

Dynamic Matrix Control with Model Truncation Error Compensation

动态矩阵控制（ＤＭＣ）的模型向量存在截断误差时会使系统产生动态偏差．截断误差越大，动态偏差亦越大，甚至造成系统不稳定．文中分析了产生动态偏差的机理，提出了一种根据截断误差大小选取不同位移矩阵来校正截断误差的方法，减小了截断误差对系统性能的影响．改进后的ＤＭＣ允许模型向量存在一定的截断误差，从而能以较小的建模时域或较高的采样频率实现高性能的ＤＭＣ．仿真结果表明，该方法几乎能完全消除模型向量截断误差的影响，适用于开环阶跃响应为Ｓ形的对象以及开环响应最后区段单调变化的对象．

This paper analysed generating mechanism of the dynamic error induced by the model truncation error and presented a method of varying shift matrix to reduce the effect of the model truncation error on system performance. A certain truncation error with higher sampling ferquency and/or smaller control horizon can be used to get high performance of control.The simulations show that this method can almost absolutely eliminate the dynamic error and can be applied to those plants whose open loop step responses are S form and those plants with monotonous form in the last section of open loop step responses.