Modelling and control of an AC/AC boost-buck converter

A single-phase, four-switch AC/AC power conditioner with active filtering is proposed, based on the DC/DC boost-buck topology. The circuit is designed as a link between a single-phase utility grid and a single-phase consumer (up to ≈10 kVA). This converter is used in a feasibility study for a power utility company to enable peak shaving by means of grid voltage reduction, while satisfying supply conditions. This requires a simple AC/AC converter with both step-up and step-down capabilities. The proposed converter has two control inputs to independently control both the input power factor and the output voltage. Present a feedback control algorithm needed for converter operation under dynamical grid disturbances and load variations. The controller uses a vector-control like approach with a discrete Fourier transformation in the control loop. The resulting digital controller can easily be integrated for mass production