基于小波基函数的预测函数控制

Predictive Functional Control Based on Wavelet Function

针对传统PFC只能对预测时域内有限的几个拟合点进行拟合,未考虑整个预测时域整体逼近误差性能的优化,系统的控制品质受到损害的问题,提出一种基于小波基函数的预测函数控制方法.利用小波的紧支局部性和多尺度分析特性,对基函数的个数和位置分布可根据系统控制精度和不同预测时段的不同逼近要求进行灵活设置,既保证了整体误差性能的优化,又突出了重要拟合点的逼近要求,并实现了优化变量的集结.理论分析和仿真应用表明,该方法比传统的PFC有更好的快速性和抗干扰性,对于快速系统应用场合具有良好的应用前景.

A predictive functional control strategy using wavelet as basis function is developed. Traditional PFC only can fit limited several points in horizon of prediction with reference locus, and is unable to optimize the target function to the whole horizon of prediction. Because the wavelet has the properties of compact support and multi- scale analysis, the number of wavelet functions and their location are set flexibly according to the system＇s controlling precision and the different requirements of approximation precision at different intervals of the horizon. So the target function of the whole horizon is optimized and some important points are emphasized. Meanwhile, the optimal parameters are aggregated. The theoretical analysis and the simulation show that this approach has better rapidity and anti-interference ability compared with traditional PFC. This approach also has good application prospect in the filed of fast systems.