This article proposes a dynamic characteristic improvement of phase-shift full-bridge center-tapped (PSFB-CT) converter using a model predictive control (MPC) method. The PSFB-CT converter is widely used for low-voltage dc-dc converters in electric vehicles. In general, its output voltage is a control object which is usually controlled using a proportional-integral control-based output voltage controller and current controller. However, it has a disadvantage such as undesirable dynamic characteristic of the PSFB-CT converter and the necessity of gain tuning. Especially, if the gain of the PI control is increased to improve the dynamic characteristic of the PSFB-CT converter, an overshoot of the output voltage can occur. In this article, the advanced voltage control using the MPC method is proposed to improve the dynamic characteristic of the PSFB-CT converter without overshoot of the output voltage. As a result, the proposed method has advantages with not only fast dynamic characteristic but also robustness from a sudden change of load impedance. The effectiveness of the proposed MPC method was proved by the simulation and experimental results.
This work was supported in the part by the Korea Institute of Energy Technology Evaluation and Planning funded by the Korea government (MOTIE) under Grant 20182410105160 and in part by the Human Resources Program in Energy Technology of the Korea Institute of Energy Technology Evaluation and Planning funded by the Ministry of Trade, Industry and Energy, Republic of Korea under Grant 20194030202370.
