tailieunhanh - Design of high density transformers for high frequency high power converters - Wei Shen

In Design of high density transformers for high frequency high power converters, the abovementioned issues of high-frequency transformers are explored, particularly in regards to high-power converter applications. Loss calculations accommodating resonant operating waveform and Litz wire windings are explored. Leakage inductance modeling for large-number-of-stand Litz wire windings is proposed. The optimal design procedure based on the models is developed. | Design of High-density Transformers for High-frequency High-power Converters by Wei Shen Dissertation submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy In Electrical Engineering Dr. Dushan Boroyevich Committee Co-Chair Dr. Fred Wang Committee Co-Chair Dr. Jacobus Daniel van Wyk Committee Member Dr. Guo-Quan Lu Committee Member Dr. Yilu Liu Committee Member July 2006 Blacksburg Virginia Keywords High-frequency Transformer High power density Core loss calculation Leakage inductance calculation Transformer optimal design Design of High-density Transformers for High-frequency High-power Converters Wei Shen ABSTRACT Moore s Law has been used to describe and predict the blossom of IC industries so increasing the data density is clearly the ultimate goal of all technological development. If the power density of power electronics converters can be analogized to the data density of IC s then power density is a critical indicator and inherent driving force to the development of power electronics. Increasing the power density while reducing or keeping the cost would allow power electronics to be used in more applications. One of the design challenges of the high-density power converter design is to have high-density magnetic components which are usually the most bulky parts in a converter. Increasing the switching frequency to shrink the passive component size is the biggest contribution towards increasing power density. However two factors losses and parasitics loom and compromise the effect. Losses of high-frequency magnetic components are complicated due to the eddy current effect in magnetic cores and copper windings. Parasitics of magnetic components including leakage inductances and winding capacitances can significantly change converter behavior. Therefore modeling loss and parasitic mechanism and control them for certain design are major challenges and .

• Thạc sĩ - Tiến sĩ - Cao học
• Design of high density transformers
• High frequency high power converters
• High power converter applications
• Conventional high frequency magnetic materials
• Characteristics of nanocrystalline materials
• Transformer specifications of the PRC operation