The analysis of average sliding control method applied on Sheppard-Taylor power factor correction converter

摘要

This paper presents an average sliding control (ASC) method to be used in power factor correction (PFC) converters to decrease the total harmonic distortion (THD) of the input current by eliminating the input current harmonics. The ASC algorithm is adapted to digital signal processor due to its well-known properties such as robustness, stability and good regulation in a wide range of operating conditions. The control approach is operated in continuous conduction mode. In this approach, all the duty cycles required to achieve unity power factor in a half line period are calculated in advance using ASC method. The feed forward is also used in the control algorithm using rms value of the input voltage. The implementation of feed forward improves the converter performance to obtain a near unity power factor correction with a lower input current THD. The converter used in simulation and experimental studies is a Sheppard-Taylor PFC converter. The stability analysis of proposed control method is performed with the effect of changes in input voltage and load. In addition, the performance of ASC method is compared with UC3854AN traditional analog PFC control method. The experiments performed in the laboratory for different cases of operation verify the theoretical and simulation studies performed in MATLAB/Simulink. The experimental results are satisfied by IEC 61000-3-2 Current Harmonic Standard.