Research Initiation: Combined Thermal-Magnetic Model for Design of High-Frequency Power Transformers

研究启动：用于高频电力变压器设计的热磁组合模型

• 批准号: 8809786
• 负责人: Douglas Nelson
• 金额: $ 6.96万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-06-15 至 1990-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8809786&HistoricalAwards=false
• 关键词: Research; Initiation; Combined; Thermal; Magnetic

Switching frequencies in the megahertz range are being used in the development of power supplied for the next-generation computers and other applications. The internal heat generation in a transformer core is proportional to frequency, local magnetic field strength and material properties. The minimum core volume required for a high- frequency design is limited by core loss and thermal considerations, yet no method for design optimization currently exists. This project considers the mechanisms of thermal-magnetic coupling and enhanced heat transfer for transformer design. A generic finite-element model of a power transformer that accounts for coupling between the temperature field, magnetic field, geometry and material properties will be developed. The model will be validated by an electrical energy balance to determine core and winding losses, and by infrared thermal imaging to map the surface temperatures of prototype high- frequency power transformers. The proposed research will improve the design tools available for high-frequency magnetics. This work is expected to show for the first time the impact of coupling between the magnetic and thermal fields on design optimization. This work will also demonstrate the performance gains obtainable through improved heat transfer away from the transformer and the resulting decrease in temperature level. Previous work has neglected heat transfer enhancement altogether. The results of this research will allow industry to further advance power electronics technology.

Megahertz范围内的切换频率正在用于为下一代计算机和其他应用提供的电源开发。 变压器芯中的内部热量产生与频率，局部磁场强度和材料特性成正比。 高频设计所需的最小核心体积受到核心损耗和热考虑因素的限制，但目前不存在设计优化的方法。 该项目考虑了用于变压器设计的热磁耦合和增强传热的机制。 电力变压器的通用有限元模型将解释温度场，磁场，几何形状和材料特性之间的耦合。 该模型将通过电能平衡来验证，以确定芯和绕组损失，并通过红外热成像来绘制原型高频功率变压器的表面温度。 拟议的研究将改善可用于高频磁力的设计工具。 预计这项工作将首次显示磁场和热场之间的耦合对设计优化的影响。 这项工作还将证明可通过改进的热传递远离变压器获得的性能增长，并导致温度水平降低。 以前的工作已经完全忽略了传热增强。 这项研究的结果将使行业能够进一步推进电力电子技术。