混合型高频隔离直流变换器及其滞环控制策略研究
发布时间：2019-04-28 18:12
【摘要】：近年来,由于在电压转换和电能质量变换方面的优良特性,电力电子变压器作为传统变压器的替代正受到人们的广泛关注。其中,隔离级DC-DC变换器作为电力电子变压器的中央关键环节,正被国内外学者作为重点课题深入研究。在诸多的研究成果中,以LLC型谐振变换器和DAB直流变换器为主拓扑的变换装置成为了学者们关注的焦点。这两种变换器在保证高电压等级电能变换的同时,均具备软开关能力。其中,LLC型谐振变换器在全负载范围内均能保证软开关工作状态,并且具有恒压调节能力,但其功率变换能力却受到谐振电容电流能力的限制。而DAB线性直流变换器虽然具有大功率电能变换能力,但由于其输出电压与前后对应桥臂移相角之间并无直接联系,因此需要较为复杂的控制系统与其配合,这无疑增加了变换器整体模块的复杂程度,降低了系统可靠性。本文提出一种基于LLC谐振型变换器与DAB直流变换器混合运行的混合型高频隔离DC-DC变换器。该变换器利用LLC谐振变换器恒压调节的特性箝位模块两端电压,并利用DAB直流变换器的大功率能力承担大部分功率变换任务。在克服LLC型谐振变换装置功率变换能力受到谐振电容电流能力限制的同时,极大地简化了模块整体的控制策略复杂程度。同时,为该变换器设计了一种简单有效的闭环控制策略,该控制策略与所提出的结构相配合,能够保证在增减负荷时变换器模块能够快速回复至稳定状态。最后,搭建了混合型高频隔离直流变换器实验样机,验证了所提出结构和控制策略的有效性和正确性。
[Abstract]:In recent years, due to the excellent characteristics of voltage conversion and power quality conversion, power electronic transformers, as the replacement of traditional transformers, have been paid more and more attention. As the central key link of power electronic transformer, isolation level DC-DC converter is being deeply studied by scholars at home and abroad. Among the many research achievements, LLC resonant converter and DAB DC-DC converter are the main topology converter, which has become the focus of scholars' attention. Both converters have soft switching capability while ensuring high voltage level power conversion. Among them, the LLC resonant converter can guarantee the soft-switching working state in the full load range, and has the ability of constant voltage regulation, but its power conversion ability is limited by the resonant capacitance current capability. Although the DAB linear DC / DC converter has high power conversion capability, there is no direct connection between the output voltage and the phase shift angle of the corresponding bridge arm, so the complex control system is needed to cooperate with it. This undoubtedly increases the complexity of the whole module of the converter and reduces the reliability of the system. This paper presents a hybrid high frequency isolated DC-DC converter based on hybrid operation of LLC resonant converter and DAB DC / DC converter. The converter uses the voltage at both ends of the characteristic clamp module regulated by the constant voltage of the LLC resonant converter and uses the high power capability of the DAB DC / DC converter to undertake most of the power conversion tasks. While overcoming the limitation of the power conversion ability of LLC type resonant converter by the resonant capacitance current capability, the complexity of the control strategy of the whole module is greatly simplified. At the same time, a simple and effective closed-loop control strategy is designed for the converter. This control strategy, in conjunction with the proposed structure, can ensure that the converter module can return to the stable state quickly when the load is increased and reduced. Finally, an experimental prototype of hybrid high frequency isolated DC / DC converter is built to verify the validity and correctness of the proposed structure and control strategy.
【学位授予单位】：东北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM46
[Abstract]:In recent years, due to the excellent characteristics of voltage conversion and power quality conversion, power electronic transformers, as the replacement of traditional transformers, have been paid more and more attention. As the central key link of power electronic transformer, isolation level DC-DC converter is being deeply studied by scholars at home and abroad. Among the many research achievements, LLC resonant converter and DAB DC-DC converter are the main topology converter, which has become the focus of scholars' attention. Both converters have soft switching capability while ensuring high voltage level power conversion. Among them, the LLC resonant converter can guarantee the soft-switching working state in the full load range, and has the ability of constant voltage regulation, but its power conversion ability is limited by the resonant capacitance current capability. Although the DAB linear DC / DC converter has high power conversion capability, there is no direct connection between the output voltage and the phase shift angle of the corresponding bridge arm, so the complex control system is needed to cooperate with it. This undoubtedly increases the complexity of the whole module of the converter and reduces the reliability of the system. This paper presents a hybrid high frequency isolated DC-DC converter based on hybrid operation of LLC resonant converter and DAB DC / DC converter. The converter uses the voltage at both ends of the characteristic clamp module regulated by the constant voltage of the LLC resonant converter and uses the high power capability of the DAB DC / DC converter to undertake most of the power conversion tasks. While overcoming the limitation of the power conversion ability of LLC type resonant converter by the resonant capacitance current capability, the complexity of the control strategy of the whole module is greatly simplified. At the same time, a simple and effective closed-loop control strategy is designed for the converter. This control strategy, in conjunction with the proposed structure, can ensure that the converter module can return to the stable state quickly when the load is increased and reduced. Finally, an experimental prototype of hybrid high frequency isolated DC / DC converter is built to verify the validity and correctness of the proposed structure and control strategy.
【学位授予单位】：东北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM46
【参考文献】
相关期刊论文 前9条
1 江添洋;张军明;汪i裆，
本文编号：2467847
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