Control of non-minimum-phase nonlinear systems through constrained input-output linearization (original) (raw)

Output Tracking of Non-minimum Phase Nonlinear Systems Through Exact Linearization

2013

In this paper, we develop a method to design the input control to track the output of a nonminimum-phase nonlinear systems asymptotically. The design of the control inputs is based on an exact linearization. To perform the exact linearization, the other output should be selected such that its relative degree is equal to the dimension of the system. Furthermore, the desired output of the output which has been selected will be set based on the desired output of the original system. In applying the input control which is obtained via output-input linearization sometimes led to singularity. To overcome this singularity problem, polynomial control is developed around the point of singularity.

Robust Output Feedback of Minimum Phase Nonlinear Systems

Tanzania Journal of Engineering and Technology, 2007

A robust output feedback controller is synthesized for minimum phase multivariable nonlinear systems based on the differential geometry approach. Using the internal model control structure within the input-output (I/O) linearization framework, the controller is combined with a closed-loop observer to estimate transformed states in the outer-loop. It is shown that the controller-observer combination achieves robust tracking and estimation using simple tuning parameters. The effectiveness of the proposed system is illustrated by a simulation example for control of concentration in a chemical reactor.

Feedback linearizing control of a fluidized bed reactor

The design of an adaptive nonlinear controller for the control of a fluidized bed reactor is derived by using exact linearization techniques. Reset action and parameter adaptation are used to make more robust the precise compensation of nonlinear terms, which is called for in the linearization technique. A nonlinear antiwindup mechanism is introduced to handle reset windup problem and to provide fast response without large overshoot. Simulation results show that the proposed adaptive controller guarantees good setpoint tracking. The developed estimation algorithm allows accurate estimation of the parameters for which the regressor component is not zero.

Feedback Control of Stable, Non-minimum-phase, Nonlinear Processes

A nonlinear control law is presented for stable, multiple-input, multiple-output processes, whether their delay-free part is minimum- or non-minimum-phase. It is derived by exploiting the connections between continuous-time model-predictive control and input-output linearization. The dierential-geome tric, control law induces a linear closed-loop response approximately. It has a few tunable parameters (one for each controlled output), and thus, is easily tuned.

The Output Tracking Control of a Nonlinear Non-Minimum Phase System

2013

In this paper, we study the tracking control problem for a nonlinear system in which the zero dynamics may be unstable. The objective here is to approximate the nonlinear system by another singularly perturbed system by using a small singular perturbation parameter  . The proposed approach is based on the methodology of exact input output linearization control, the integrator backstepping approach and the theory of singularly perturbed systems. The performance of the suggested approach is evaluated in an illustrative inverted cart-pendulum example. Keywords—Non minimum phase system, integrator backstepping approach, input output linearization, singular perturbed system, tracking control.

Dynamic output feedback control of minimum-phase multivariable nonlinear processes

Chemical Engineering Science, 1994

Abttact-This paper CCNILX.~F~S the synthesis of dynamic output feedback controllers foe minimum-p& multjwuiable nonlinear procesw.s with a nonsing&r characteristic matrix. Statespace controller realizetions are derived that induce a linear input/output behavior of general Iorm in the closed-loop system. A combination of input/output linearizing state leedback laws and state observers is ctnpIoyed for the derivation of rhe oontrollers. For open-loop stable pr-ses, the procerss model is used as an open-loop state observer. In the more. general ca3c of possible open-loop instability, a reduced-order obmrver is used PRODROMOS hOUnDIs and -TAS KRAVAUIS pendently, but is incorporated in the controller synthesis.

Dynamic output feedback control of nimimum-phase nonlinear processes

Chemical Engineering Science, 1992

Abstmct-This paper concerns the synthesis of dynamic output feedback controllers for minimum-phase nonlinear processes. The problem is addressed first for open-loop stable and then for general minimumphase nonlinear processes, leading to one-and two-degree-of-freedom controllers, respectively. The synthesis of the controllers essentially Involves combination of state feedback and state observers. An input/output interpretation of the resulting control structures illustrates the importance of alternative statcspace realizations of the process inverse for the controller implementation. Internal stability conditions are derived for the closed-loop system. Simulation studies in a chemical reactor example illustrate the application of the control method&gy developed.

Application of Input-Output Linearization

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Publisher InTech A trend of inverstigation of Nonlinear Control Systems has been present over the last few decades. As a result the methods for its analysis and design have improved rapidly. This book includes nonlinear design topics such as Feedback Linearization, Lyapunov Based Control, Adaptive Control, Optimal Control and Robust Control. All chapters discuss different applications that are basically independent of each other. The book will provide the reader with information on modern control techniques and results which cover a very wide application area. Each chapter attempts to demonstrate how one would apply these techniques to real-world systems through both simulations and experimental settings.