一种低电压尖峰的高增益Y源-LLC变换器

A High Step-up Y-source-LLC Converter With Low Voltage Spike

为推动新能源接入直流配电网,减少变换环节和损耗,隔离型高增益DC/DC变换器是关键接口设备。因此,提出一种低电压尖峰的高增益Y源-LLC变换器,结合Y源阻抗网络和LLC谐振腔的增益特性,实现更高的升压能力,降低电压尖峰。进一步提出脉冲宽度调制和脉冲频率调制相结合的运行方式,在缩小开关频率调整范围的同时,实现全功率下宽输入输出电压工作范围,提高变换器在新能源直流并网中的适用性。最后,对所提变换器性能进行分析,搭建实验样机验证其可行性和理论分析的正确性。

The isolated high step-up DC/DC converter is the key interface equipment to promote the new energy to access the DC distribution network,simplify the conversion process,and reduce the power loss.Therefore,a high stepup Y-source-LLC converter with low voltage spike is proposed.It combines the step-up feature of the Y-source impedance network and LLC resonant tank to achieve better step-up performance and mitigate the voltage spike on the DC link.Furthermore,by combining the pulse width modulation and pulse frequency modulation,the proposed converter can operate at wide input and output voltage range while narrowing the operating frequency range which improves its applicability in accessing the new energy to the DC grid.Its performance is analyzed.Finally,an experimental prototype is built to verify the proposed converter's feasibility and the theoretical analysis's correctness.