A Turbo Fan Nonlinear Model and a Gain Scheduling Control Strategy Design

Leonardo Andrades and Manuel Olivares


Modelling, Parametric Identification, PID Control, Gain Scheduling


In this paper, a nonlinear static model of a variable speed turbo fan is obtained. This static model is used to simulate the dynamic behavior of a pneumatic circuit composed of a turbo fan, an input valve, an output valve and the corresponding piping of a teaching and research installation that emulates a typical industrial gas extraction system. For this, the whole system is phenomenologically modeled, getting a model able to reproduce the surge phenomena present in this type of pneumatic circuits. As the dynamic system behavior is multivariable and highly nonlinear, presenting a stable zone limited by the surge line,a single PI flow controller tuned using a first order linear model obtained from a step response at one specific stable operating point shows the required closed loop response only for that operating point. To overcome that, a novel PI and GPC gain scheduling control strategies based on two experimental linear models are proposed and validated by simulation. Both gain scheduling closed loop system responses, to set-point changes and input and output disturbances, are compared against each other and evaluated, showing a better performance than the usual single linear model tuned PI control strategy.

Important Links:

Go Back