一种单级全桥高频谐振AC/AC变换器

A Single-stage Full-bridge High Frequency Resonant AC/AC Converter

单级高频谐振AC/AC变换器将工频交流输入电压变换为高频(一般大于100k Hz)交流输出电压,主要由功率因数校正、高频谐振逆变两个变换单元构成,可用于一种模块化多路输出LED驱动电源。该文提出了一种单级全桥高频谐振AC/AC变换器,对该变换器进行了拓扑推演,阐述了变换器的工作原理,对其性能进行了详细分析并根据性能要求确定了相关预设参数,再根据已知和预设参数,完成了主电路参数的定量设计,最后根据确定的参数搭建了一台额定输出功率为200W的实验样机并进行了相关实验验证,实验结果表明输入功率因数可达0.93,直流母线电容电压最高为440V,输出电压总谐波畸变率(totalharmonicsdistortion,THD)小于5%,满足实际应用要求。

A single-stage high frequency resonant AC/AC converter transfers AC-line input voltage into high frequency sinusoidal output voltage, which consists of two power conversion units, that is, power factor correction unit and high frequency resonant DC/AC unit, and it can be used to derive a modular multi-channel constant current LED driver. By adopting a full-bridge resonant converter to reduce the THD of the output voltage, a single-stage full-bridge high frequency resonant AC/AC converter was proposed in this paper. The operating principle was described and the performance analysis was presented in detail. Moreover, the quantitative parameter design method of the main circuit was presented, which was suitable for other single-stage AC input converters, such as single-stage PFC rectifier. Finally, a 200 W prototype has been built and tested to verify the correction of theory analysis and parameter design related. The experimental results show that the input power factor is around 0.93 and the maximum voltage of the DC bus capacitor is 440 V, moreover, the THD(total harmonics distortion,THD)of the output voltage is below 5%, which meet the practical application requirements.