Model reference adaptive control design for the buck-boost converter

In this study, a model reference adaptive digital control scheme is proposed for the buck-boost converter. The control design of the buck-boost converter is a challenging work because the buck-boost converter, which is a non-minimum phase (NMP) system, has a right half-plane zero. This controller design is based on the small signal model of the buck-boost converter and a reference model. A cost function of the output error and weighting control input is minimized for the buck-boost converter using the model reference adaptive control scheme. In the case that the plant parameters are uncertain (or unknown), a digital controller with model reference adaptive control scheme is proposed for the buck-boost converter using the recursive least-squares (RLS) algorithm to estimate the uncertain parameters. To verify the validity of the proposed controller, experimental set-up is built for the buck-boost converter and the fully digital adaptive controller is implemented by a digital signal processor TMS320-F28335. From the experimental results, sound performances on voltage regulation can be achieved for the buck-boost converter with uncertain parameters using the proposed controller.