Exact feedback linearisation optimal control for single‐inductor dual‐output boost converter
Jia‐Rong Wu, Yimin Lu
Abstract
To minimise the cross‐regulation of single‐inductor multiple‐output switching converters, an exact feedback linearisation (EFL) optimal control strategy is proposed in this study. Using the single‐inductor dual‐output (SIDO) boost converter as an example, an affine non‐linear system based on the non‐linearity of the system is established, the mechanism of the low‐voltage output of the SIDO boost converter is analysed in detail. Then the qualification of the established model for EFL is theoretically confirmed. Meanwhile, the corresponding output functions for the linearisation of the non‐linear system in Brunovsky normal form are constructed, and the theoretical grounds supporting the ability of the output functions to track the reference outputs are further investigated. In addition, the optimal control technology is applied to EFL control to obtain the non‐linear control law of the system. Furthermore, the design method of optimal feedback coefficients is given, and a SIDO boost converter system with low‐voltage output is designed and realised. The simulation results show that this control strategy provides a better regulation performance than common‐mode and differential‐mode voltage control strategies and that it can effectively minimise the cross‐regulation of the system. Finally, the experimental results further verify the correctness and effectiveness of the proposed control strategy.