Relay sliding mode control of multiloop systems based on the input-output model

Sliding mode control was originally defined using the state-space formulation and this tradition continues to be dominant in sliding mode studies. As an alternative, a sliding mode approach based on the input-output representation of systems was proposed for relay controlled systems. Recent studies on relay sliding mode control based on the input-output representation have shown that this approach is a very simple, yet very effective control method. This paper aims to study the performance of this approach on multiloop systems. Conditions for sliding motion in multiloop relay systems and the robustness of the technique are presented, along with a computer simulation and real application, proving the effectiveness of the method.