Approximate feedforward control

Disturbances are inevitable in most control systems. They drive the systems away from their set points. It takes time for feedback control to reject them. The feedforward control offers great potentials for regulation performance if the disturbances are measurable. One obstacle for feedforward control implementation is that the theoretical one is unrealizable for various reasons. In this paper, a new feedforward control design approach based on frequency response approximation is proposed and performs much better than the existing method in the literature. A performance measure is defined to assess if the feedforward control can outperform feedback control alone and analytical conditions are derived to determine such a measure a prior. Simulation is presented for illustration of our method.

[1]  Hua Zhong,et al.  Feedforward control for disturbance rejection: Model matching and other methods , 2012, 2012 24th Chinese Control and Decision Conference (CCDC).

[2]  Jonathan Love,et al.  Process Automation Handbook: A Guide to Theory and Practice , 2007 .

[3]  Graham C. Goodwin,et al.  Feedforward model predictive control , 2011, Annu. Rev. Control..

[4]  Robert R. Bitmead,et al.  Feedforward for stabilization in the presence of constraints , 2012 .

[5]  Tore Hägglund,et al.  Low-order feedforward controllers: Optimal performance and practical considerations , 2014 .

[6]  Gene F. Franklin,et al.  Feedback Control of Dynamic Systems , 1986 .

[7]  José Luis Guzmán,et al.  Improving feedforward disturbance compensation capabilities in Generalized Predictive Control , 2012 .

[8]  Jacinto L. Marchetti,et al.  Designing and tuning robust feedforward controllers , 2004, Comput. Chem. Eng..

[9]  Tore Hägglund,et al.  Simple tuning rules for feedforward compensators , 2011 .

[10]  Chang Chieh Hang,et al.  Single-loop controller design via IMC principles , 2001, Autom..

[11]  Qiang Bi,et al.  High-performance conversions between continuous- and discrete-time systems , 2001, Signal Process..

[12]  Jian Zhang,et al.  Internal model based robust inversion feedforward and feedback 2DOF control for LPV system with disturbance , 2013 .

[13]  W. Davidon,et al.  Mathematical Methods of Physics , 1965 .

[14]  Ian Postlethwaite,et al.  Feedforward control: a full-information approach , 2001, Autom..

[15]  James Stuart Tanton,et al.  Encyclopedia of Mathematics , 2005 .

[16]  Guoqiang Peter Zhang,et al.  Neural network forecasting for seasonal and trend time series , 2005, Eur. J. Oper. Res..