Modelling, design and control of a SEPIC power factor corrector for single-phase rectifiers: experimental validation (original) (raw)
In this paper, a new general case switching-function-based model is proposed for a DC-to-DC single ended primary inductance converter (SEPIC). Compared to conventional buck or boost converters, this topology allows a low current ripple at the input for a relatively low level of the DC-bus voltage. The converter is used as a power factor correction (PFC) circuit for a single-phase rectifier and, based on the obtained model, steady-state analysis is performed and new design criteria were established for a proper selection of the inductors and capacitors. In order to verify the performance of the converter in PFC applications, a simple hysteretic-based feedback control is implemented and verified through simulations. For validation purpose, experiments are carried out on a 1kW laboratory prototype of the converter. The system performance is evaluated in terms of source current total harmonic distortion (THD), voltage regulation, robustness and dynamic behaviour.