Implementation of sliding control with washout filter in boost and buck converters

This paper presents the analysis, design, and implementation of a two-stage 
power conversion system consisting of a boost converter and a buck 
converter. Both converters were controlled using a sliding-mode control 
based on a washout filter. The system was supplied with an alternating 
current (AC) voltage source that was rectified using a diode bridge. The 
main objectives are to improve the power factor (PF) in the boost stage and 
regulate the output voltage in the buck stage. In the first stage, sliding-mode 
control is applied to shape the input current according to the rectified 
voltage, increasing the PF and reducing harmonic distortion. In the second 
stage, the same control approach is used to maintain a constant output 
voltage under load variations and disturbances. This study includes the 
mathematical modeling of both converters, control design, and simulation 
results in PSIM. The results show that the proposed sliding-mode control 
strategy effectively enhances energy efficiency, stabilizes the output voltage, 
and significantly improves the PF, making it suitable for robust and efficient 
power conversion systems.