Photovoltaic optimizer is crucial for solar-powered aircraft applications.Considerding the high switching frequency of GaN,a planar inductor for four switch buck/boost (FSBB) is designed,which make an optimal balance between inductor size and loss.At the same time,considering the maximum power point tracking and battery management of the system, the working principle and control strategy of FSBB photovoltaic optimizer based on GaN devices are analyzed. The mode switching is smooth by dynamic switching frequency.Finally,a prototype with a maximum power of 400W is built and the correctness of the theoretical analysis is verified.The power optimizer is only 35mm*37mm*7mm,and the efficiency is up to 97.1% under the maximum power.

photovoltaic optimizer,GaN,planar inductor,high efficiency