Extended-State Observer-Based Controller for Cuk Converter

An extended state-observer (ESO) based controller design and analysis of the Cuk converter is discussed in this paper. It estimates the un-modeled disturbance using an extended state and compensates it internally to the control law. This design takes the parameter variation into account and hence yields better dynamic performance. For comparison purposes, the PI (proportional plus integral) and conventional PID controllers are also designed and analyzed. Upon transforming the PI, PID controllers in the disturbance observer-based control form, the integral action represents as an estimation of disturbance. After that, a theoretical analysis is carried out to assess fairly and show the performance improvement of the ESO-based controller. The finding indicates that without using extra sensors, the proposed controller is able to exhibit better dynamic response and it is also robust against the parameter variations. Analytical findings are verified through simulations and sample experimental results.