It is well known that actuator saturation can cause destabilization and degradation in performance; similar problems are faced when actuation is quantized. This paper proposes the design of an anti-windup compensator for systems with actuators that are limited to a finite number of quantization levels. This combination of discrete level actuation and saturation poses a unique anti-windup problem that has not yet been solved. To surmount this combined issue, an anti-windup compensator is proposed which provides ultimateboundedness of the system state within a prescribed region, and also guarantees that the state does not stray outside a larger compact set. A numerical simulation example illustrates the effectiveness on a rigid-body system which inspired this work. 
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                            Two-stage anti-windup compensation for systems subject to actuator quantization and saturation
                        
                    
    
            This paper proposes a two stage anti-windup compensation scheme for systems subject to both input saturation and input quantization. The paper makes two main contributions: (i) it proposes a new partitioning of the saturation/quantization nonlinearity; and (ii) it formulates and solves a two-stage anti-windup problem on the basis of this partitioned nonlinearity. The anti-windup compensator contains two distinct elements: one to assuage the effects of quantization, the other to do the same when saturation occurs. Theoretical results provide conditions which must be satisfied in order for the two-stage anti-windup compensator to bestow stability on the resulting closed-loop system. These results are expressed as linear matrix inequalities and naturally lead to algorithms for anti-windup design. Simulation examples illustrate the effectiveness of the techniques. 
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                            - Award ID(s):
- 2137030
- PAR ID:
- 10563250
- Publisher / Repository:
- Taylor & Francis
- Date Published:
- Journal Name:
- International Journal of Control
- ISSN:
- 0020-7179
- Page Range / eLocation ID:
- 1 to 14
- Subject(s) / Keyword(s):
- Anti-windup compensation constrained control quantized control
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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