Reduced-order controller design for Cuk converters based on objective holographic feedback

Since the Cuk converter is a non-minimum phase system with an unstable internal dynamic, it is challenging to employ control methods such as input-output linearization to ensure the closed-loop system stability. This paper proposes an objective holographic feedback nonlinear control (OHFNC) method without static deviation to regulate fourth-order Cuk converters. A Cuk converter operating in the continuous conduction mode is adopted, and the input inductor current and output capacitor voltage of the system are selected as control target quantities. The OHFNC method aims to configure a nonlinear system with poles near the equilibrium point, and place them in desired positions. The target quantities are separately constrained by feedback coefficients, which forces them to converge to their corresponding reference trajectories. Accordingly, an integration link is introduced to compensate for the reference current error when the system is heavily loaded. Finally, simulation and experimental results show that the OHFNC method has a stronger robustness and a faster transient response than fractional-order PI lambda dual-loop control.