Variable structure control: Difference between revisions

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[[Variable structure control]], or '''VSC''', is form of [[Classification of discontinuities|discontinuous]] [[nonlinear control]]. The method alters the [[dynamic system|dynamics]] of a [[nonlinear system]] by application of a high-frequency ''switching control''. The [[state space (controls)|state]]-[[feedback]] control law is ''not'' a [[continuous function]] of time; it ''switches'' from one smooth condition to another. So the ''structure'' of the control law ''varies'' based on the position of the state trajectory; the method switches from one smooth control law to another and possibly very fast speeds (e.g., for a [[countably infinite]] number of times in a finite time interval). Variable structure control (VSC) and associated sliding mode behaviour was first investigated in early 1950's in the Soviet Union by Emelyanov and several coresearchers.<ref name="E1967">{{citation|title= Variable Structure Control Systems|editor1-last=Emelyanov|editor1-first=S.V.|publisher=Nauka|___location=Moscow|date=1967}}</ref>.

Presently, the main mode of VSC operation is [[sliding mode control]] (SMC). The strengths of SMC include: