Hybrid robust controller design for a two mass system with disturbance compensation

In this paper we describe a robust control method for when a torque or inertia change in a two mass system. There are various controllers that represent a robustness. Especially, the disturbance observer (DOB) and H _infin of them are well known for their efficiency with respect to a disturbance rejection. Actually, there is method to make use of two controllers together as a cascade type. But the performance of this control is not efficient due to a fault in that the system degree increases when it designs a controller. In this paper, a hybrid type disturbance compensation is proposed for robust control methods. Basically, a hybrid robust controller is driven by the H _infin controller, and a H _infin control of the limited scope of a control for a disturbance when compared with the disturbance observer (DOB) will be compensated for by the H _infin control input. We performed a DOB and H _infin comparison simulation to prove the performance of the controller that is proposed in this paper. We performed simulations for a change in the torque and inertia and found that the proposed controller showed a small error. For a verification, we performed simulations by using MATLAB/SIMULINK.