Nonlinear Multivariable Design by Total Synthesis

In a recent publication [1], Bristol has presented an application theorist´s view of process control design as it really exists and has challenged others to do likewise for areas within their own purview. This paper continues just such an effort [2,3,4] by the authors within the domain of nonlinear multivariable control of gas turbine engines. Under examination is the fundamental notion that linear controller descriptions, obtained from local actions of nonlinear objects, may be recombined to produce global nonlinear control action, with sufficient integrity to effect closed loop design. Total Synthesis refers to a top-down strategy of Nominal Design and Feedback Synthesis. This paper extends the study of the Nominal Design Problem (NDP) to nonlinear cases, and presents a new case study of robust feedback synthesis for gas turbine control design.