Keywords: power electronics, power factor correction, PFC, single-phase rectifiers, Sheppard-Taylor topology, average modelling, multi-loop control, simulation, hysteresis, PI regulator, nonlinear compensation, total harmonic distortion, THD, input power factor, DC voltage stabilisation, load regulation
Study, modelling and control of a single-phase power factor corrector based on the Sheppard-Taylor topology
In this paper, a single-phase power factor corrector (PFC) based on the Sheppard-Taylor topology is studied. A novel mathematical representation of the converter is elaborated using the state-space averaging technique. In order to emphasise the usefulness of such model, three pulse-width-modulated (PWM) multi-loops control schemes are proposed and developed in the aim of ensuring a unity power factor at the AC-source side and a regulated voltage at the DC-load side. The first one uses the simple and robust hysteretic-based controller; the second one employs a conventional PI regulator; whereas the third one is based on the model nonlinearity compensation approach. The control systems are tested through simulations under both rated and disturbed operating conditions. The system performance is evaluated in terms of source current total harmonic distortion (THD), input power factor, DC voltage stabilisation, and regulation following load variations.