| dc.description.abstract | This dissertation deliberates the problem of variable structure controller design for uncertain systems subjected to dead-zones and sector non-linearities in the inputs.
Firstly, a novel variable structure model-following control design is presented for a simple uncertain system containing single dead-zone or series nonlinearity. In this approach, given a model with ideal reference characteristics, we will propose a controller, which will force the error between the plant and the model to approach zero asymptotically. Secondly, in addition to the input nonlinearities and system uncertainties, one has to consider another source of instability arisen from time delay. Hence, a new variable structure controller is proposed for the purpose of stabilizing uncertain systems with time delay in the state and dead-zone in the input. Thirdly, because most of systems have become larger and more complicated and always accompanies with difficulty and complexity of system control, we extend the method mentioned above to an interconnected system and a new robust decentralized control scheme is proposed for uncertain large-scale interconnected systems through VSC theory. Fourthly, based on the approaches suggested in the above, a new decentralized variable structure control law is proposed for a class of uncertain time delayed large-scale systems, which with time delay in the interconnection and dead-zones or sector nonlinearities in the input.
Furthermore, for all of the above investigated systems, not only single-input cases have been discussed but also the multi-input cases have been considered. | en_US |