Disturbance compensation in digital sliding mode

This paper proposes a new approach for slow and matched disturbance suppression in digital sliding mode. The previous value of disturbance is extracted from switching function and used to make disturbance estimation, and later used in control to cancel disturbance effects. The control function is linear in state and in disturbance estimate. It may be considered chattering free since its value is zero in equilibrium if there are no disturbances.