Boundedness Analysis on Large Signal Average Model of Full-Bridge DC-DC Converter

For the full-bridge DC-DC converter, the operating points vary with the load. It is important to confirm the boundedness on the basis of the large signal average model. In this paper, the full-bridge converter with block capacitor is the subject investigated. Firstly, the large signal average model added into the correction factors is founded and formulated. The process of modeling is similar to that of converter with LLC circuit. Secondly, the boundedness analysis on the model is described so that whether the model is bounded or not can be judged. The two signals A and B directly impact the boundedness of other state variables. Lastly but very important, the numerical and experimental results are both used to verify the boundedness of the converter. No matter the load is constant or the step change, the model and the converter arc always bounded. What is more, compared with the first harmonic approximation (FHA), the theoretical analysis on the model is more in accordance with the actual converter.