Loading...

Modeling and Control of LLC Resonant Converter Based on Theories of Hybrid Systems

Barzkar, Ashkan | 2020

459 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 52679 (05)
  4. University: Sharif University of Technology
  5. Department: Electrical Engineering
  6. Advisor(s): Tahami, Farzad
  7. Abstract:
  8. In comparison to pulse width modulation (PWM) converters, the ability of soft switch-ing enables resonant converters to operate at high frequencies, as the result of which these converters enjoy high efficiency, high power density, and low electromagnetic interference (EMI). Among resonant tank topologies, the LLC resonant tank is a very desirable structure, as the LLC resonant converter can operate in boost mode and properly regulate the output voltage under light loads and despite large variations in the input voltage and/or the load. However, there are major modeling issues with resonant converters, since conventional modeling approaches cannot properly model fast dynamics of these convert-ers and nonlinear modeling approaches lead to a very awkward, unsystematic model of the converter with which stability analysis and controller design would be problematic. Resonant converters, as hybrid systems, are naturally switched systems with affine subsys-tems. Accordingly, in this thesis, the LLC resonant converter has been modeled in the form of piece wise affine (PWA) systems and a direct piece wise affine (DPWA) model of the converter was investigated. Utilizing the proposed model, no voltage controlled oscillator (VCO) is needed to drive switches of the converter. Furthermore, the input of the proposed model is a continuous vector – rather than the switching command which is a logical variable – which can be properly controlled by an appropriate controller. An appropriate controller was also designed in the thesis using the model, and both open loop and closed loop system were simulated in MATLAB/SIMULINK to verify proper working of the proposed model and designed controller, respectively. In addition, a prototype of the LLC resonant converter along with switching board have been built and were utilized to verify results using experimental outputs
  9. Keywords:
  10. Hybrid System ; Piecewise Affine System ; Modeling ; Control ; LLC Resonant Converter

 Digital Object List

 Bookmark

No TOC