A GaN-Based Microconverter Utilizing Fixed-Frequency BCM Control Method for PV Applications

This paper introduces a novel boundary conduction mode (BCM) controlled microconverter for photovoltaic (PV) application in order to provide high conversion efficiency over a wide input voltage operating range. Within the wide input range for the PV panel, there is no need to change the operating modes according to the PV panel voltage. The leakage inductance current can work in BCM with fixed switching frequency. The operation mode analysis is given first. Then, the operating principle of the proposed BCM and its implementation are introduced. Loss breakdown of the prototype using GaN devices is analyzed and compared with the same voltage-rating silicon mosfets. A 300-W microconverter was fabricated and experimental results are provided to verify the effectiveness of the proposed BCM control.