A new stabilizer for ltv internal model based system and its application to camless engine valve actuation

This paper focuses on the stabilization of an internal model based control system for reference tracking/disturbance rejection, where the physical plant is linear time invariant while the generating dynamics of the reference/ disturbance is time varying. Given the inevitable linear time varying (LTV) nature of the internal model unit resulting from the time varying generating dynamics, a critical problem to be addressed is the design of a low order and robust stabilizer for the entire augmented system. While a parameter-dependent output injection based stabilizer was introduced in our previous work, the new method proposed in this paper reduces the conservativeness in the control synthesis and thus enables a more effective control design especially for the problem involving LTI physical plant with LTV internal model dynamics. The proposed approach is then validated through experimental investigations on a camless engine valve actuation system, where robust and precise tracking performance is demonstrated.