This study introduces a dual range flyback converter, which overcomes low efficiency of the conventional flyback converter for universal mains voltages, i.e. 220 and 110 V AC mains. The topology comprises of reconfigurable primary power loops enabled by additional state switches. This combination allows the converter to run in parallel or series modes, enhancing the performance at 220 V AC high line or 110 V AC low line mains. It reduces the voltage rating of devices, supports two working points that operate in boundary conduction mode under fixed frequency and improves the utilisation of the devices. A 100 kHz, 60 W, 110 V AC or 220 V AC to 13 V DC converter has been designed and tested. The experimental results of the proposed converter have been compared against a conventional flyback converter. The results show a small improvement of performance at low voltage (110 V AC) and considerable performance improvement at high voltage (230 V AC): 0.6 and 2.3% efficiency improvement at full load, respectively.

中文翻译：

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双范围反激式拓扑，可在双电压电源上实现高效率

本研究介绍了一种双范围反激式转换器，该转换器克服了常规反激式转换器对通用市电电压（即220和110 V AC电源）的低效率。该拓扑包括由其他状态开关启用的可重新配置的主电源环路。这种组合允许转换器以并联或串联模式运行，从而提高了220 V AC高线或110 V AC低线电源的性能。它降低了设备的额定电压，支持在固定频率下以边界传导模式工作的两个工作点，并提高了设备​​的利用率。已设计并测试了100 kHz，60 W，110 V AC或220 V AC至13 V DC的转换器。拟议的转换器的实验结果已与常规反激式转换器进行了比较。