scholarly journals Fixed Frequency Pulse-Width Modulation Based Integrated Sliding Mode Controller for Phase-Shifted Full-Bridge Converters

IEEE Access ◽  
2018 ◽  
Vol 6 ◽  
pp. 2181-2192 ◽  
Author(s):  
Ming Gao ◽  
Dazhi Wang ◽  
Yunlu Li ◽  
Tianqing Yuan
Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 853 ◽  
Author(s):  
Abdul Yasin ◽  
Muhammad Ashraf ◽  
Aamer Bhatti

The key issue in the implementation of the Sliding Mode Control (SMC) in analogue circuits and power electronic converters is its variable switching frequency. The drifting frequency causes electromagnetic compatibility issues and also adversely affect the efficiency of the converter, because the proper size of the inductor and the capacitor depends upon the switching frequency. Pulse Width Modulation based SMC (PWM-SMC) offers the solution, however, it uses either boundary layer approach or employs pulse width modulation of the ideal equivalent control signal. The first technique compromises the performance within the boundary layer, while the latter may not possess properties like robustness and order reduction due to the absence of the discontinuous function. In this research, a novel approach to fix the switching frequency in SMC is proposed, that employs a low pass filter to extract the equivalent control from the discontinuous function, such that the performance and robustness remains intact. To benchmark the experimental observations, a comparison with existing double integral type PWM-SMC is also presented. The results confirm that an improvement of 20% in the rise time and 25.3% in the settling time is obtained. The voltage sag during step change in load is reduced to 42.86%, indicating the increase in the robustness. The experiments prove the hypothesis that a discontinuous function based fixed frequency SMC performs better in terms of disturbances rejection as compared to its counterpart based solely on ideal equivalent control.


2010 ◽  
Vol 450 ◽  
pp. 548-551
Author(s):  
Bo Wu ◽  
Li Xu ◽  
Xiao Dong Yu ◽  
Zhi Wei Wang ◽  
He Xu

This paper presents a new mathematical model for the pneumatic driving 6-DOF parallel robot controlled by pulse-width-modulation. The models not only overcome discontinuity of switching solenoid valve, but also change discontinuous and non-affine form into a canonical affine form. Then a sliding mode controller with fuzzy tuning is designed based on sliding mode theory and fuzzy theory and implemented on the pneumatic driving 6-DOF parallel robot position servo controlling system. The effectiveness of the controlling approach proposed here is validated by simulation data, which shows its capability of restraining the serious load coupling disturbance among channels and improving the trajectory tracking precision.


Sign in / Sign up

Export Citation Format

Share Document