Optimal Design of Wide Input Voltage Range LLC Converter in Avionics Application

It is essential for avionic systems to achieve high efficiency, compactness, and low weight. Also, the DC/DC LLC converter that is supplied from avionics DC bus is widely used to carry avionic loads, and the wide input voltage range of the bus should be considered during the design process. This paper proposes a design optimization process for LLC converter. The proposed design process is demonstrated by evaluating and comparing four different topologies with magnetic design. Based on the specifications which can be randomly set by users, by following the process, the key parameters for optimal converter design can be found. Moreover, two different magnetic core structures are considered. Eventually, combining the system’s efficiency, volume, and weight, the optimal design of each topology can be achieved. The final decision can be made based on the application’s requirement.