A new variable structure control law for multivariate uncertain plants

In this paper, a new variable structure control law that is called logic and extreme control law is proposed for multivariable linear plants with matched or mismatched uncertainties. Its esigning method, which is totally based on the plant nominal models and the uncertainties' extreme values, is also studied. Meanwhile, some direct and general relations between the uncertainties' variation ranges and the cotrol laws parameters are established. No matter what concrete forms the uncertainties have, the control law designed here ensures that the sliding mode exists; The control law got in this paper is suited to many areas, and is easy to realize in engineering.