H桥分时复用方法及其在电力电子变压器中的应用

H-bridge Time-sharing Multiplexing and Its Application in Power Electronic Transformers

能源互联网中,电力电子变压器(powerelectronic converter,PET)因功率变换级数较多,体积庞大,成本高昂,且效率不佳。为此,提出了一种有助于减少PET级数的H桥分时复用方法。首先,阐明了分时复用方法的基本原理,定义了单载波周期的工作模式,分析了变压器原边的电流特征;其次,介绍了实用的谐振式开环工作模式切换方法,理论推导了电流脉冲与谐振角度的对应关系;通过样机实验验证了所提高频变压器间歇功率传输与模式切换方法;最后,基于分时复用方法构建了新型PET,并使用电力电子仿真软件PLECS真验证了基本功能。相关方法为优化PET的拓扑与控制提供了新思路。

The power electronic converter(PET)in the energy internet,because of its multi-stage power conversions,owns a huge volume with high cost and unsatisfying efficiency.Therefore,an H-bridge power time-sharing multiplexing which contribute to reducing the stages of the PET is proposed.Firstly,the basic principle of time-sharing multiplexing is illustrated,the working modes of a single carrier cycle is defined,and the current characteristic of the primary side of the transformer is analyzed;Secondly,the practical resonant open-loop mode switching is introduced,the relationship between the current pulse and the resonant angle is theoretically deduced,and the proposed intermittent power transmission and the mode switching of the high-frequency power transformer is verified in the prototype experiments;Finally,a novel PET is constructed based on the time-sharing multiplexing with its basic functions verified by simulation with the PLECS.The relevant methods here provide a new idea for optimizing the topology and control of the PET.