Parameter based non linearity in a state variable model of a practical system: A case study


A.B.Chattopadhyay,Shazia Hasan,Sunil Thomas,



Non-linear adaptive-parameter,Small perturbation approach,DC drive,Thyristorized W-L method,silicon-controlled rectifier,


The small perturbation method is widely used in attempting to model non-linear systems. Many systems nowadays in different domains exist as adaptive-parameter type models, where the control effort is not applied as in input to the system (as is usually the case) but as a change to the parameter within the system itself. This paper attempts to analyze a non-linear adaptive-parameter type system, using the small perturbation method for linearization. The Ward-Leonard DC Motor with thyristor field control is used as a “test bench” here as it is suited for being an adaptive parameter system. The results and inferences from this study can easily be generalized to a wide variety of systems in applied mathematics, general control systems, power systems, robotics etc.


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A.B.Chattopadhyay, Shazia Hasan, Sunil Thomas View Download