壓電功率轉換裝置的設計與實現

Design & Implementation of Piezoelectric Technology Based Power Devices

劉元平(Yuan-Ping Liu)

指導教授 ： 李世光

共同指導教授 ： 吳文中 ； Francois COSTA ； Dejan Vasic(Dejan Vasic)

國立臺灣大學/工學院/工程科學及海洋工程學研究所/博士(2009年)

https://doi.org/10.6342/NTU.2009.02373

摘要

本文係發展壓電材料做為多種電力轉換裝置的關鍵元件，進而發展出壓電式電力轉換裝置。不同於目前電力轉換器使用電磁變壓器做為電能轉換關鍵元件，本論文使用壓電變壓器做為電力轉換器的關鍵元件。研究目的是希望以壓電變壓器取代電磁變壓器，來降低系統的電磁干擾、薄型化和提高轉換器的能量密度。本文主要分成壓電式冷陰極管換流器、壓電式直流對直流轉換器和壓電饋入整流器的最佳化三大部分。以往壓電變壓器主要是從最佳負載的概念做為設計的基礎。然而，實際的電力轉換器需要有電壓或電流調節的功能，在考慮電壓和電流調節的情況下，最佳負載的概念並不適合作為設計的依據。本論文改從壓電變壓器物理特性振動速度做為設計的依據，使壓電變壓器的設計更為清楚而簡潔。提出創新的設計方法使壓電變壓器的主要損耗可以被清晰的預測，而溫度的上升也可從本文所提出的設計方法中得到良好的預測趨勢。壓電式冷陰極管換流器和壓電式直流對直流轉換器都藉由此設計流程的概念，成功的設計出符合實際規格與需求的壓電變壓器，並分別實際應用在32吋液晶電視和10瓦的直流電源供應器上。此外，本論文同時分析壓電式直流對直流轉換器的電磁干擾問題。雖然壓電本身並輻射性電磁干擾的問題，使得壓電式電源轉換器有傳導性電磁干擾的問題。由於壓電的寄生電容和外接整流器的特性，使得壓電式電源轉換器的電磁干擾問題相當不同於電磁式的電源轉換器。詳細的傳導性電磁干擾分析和模型都在本論文中被分析與詳述。此外，在直流負載的考量下，由於壓電式饋入整流器為一非線性裝置，不易分析與設計。本論文提出使用壓電片的能量工作迴圈的概念，簡化過往分析複雜的問題。此外，本論文更藉由分析結果，提出最佳化的速度控制式壓電式饋入整流器。並將此技術成功的應用在壓電結構阻尼的應用上。

關鍵字

壓電變壓器 ； 切換式電源 ； 諧振式電源供應器 ； 切換式阻尼 ； 智能結構

並列摘要

In this dissertation, the piezoelectric materials were adopted to make the key components in the power device, and were further developed to piezoelectric technology based power converters. The main purpose of this dissertation is that using the piezoelectric transformers as the key component to replace the electromagnetic transformers in some power converters. The piezoelectric transformers based converter can reduce the electromagnetic interference (EMI), thickness of the converters and increase the power density of the converter. Cold cathode fluorescent lamp based inverters, DC/DC converters and the optimization of the piezoelectric layer fed rectifiers are the three main parts in this dissertation. Previous researches used the concept of the optimal loading condition as the major design criterion. However, the practical power converter requires the current or voltage regulation. Considering the power converters with the current or voltage regulation, the concept of the optimal loading condition is not suitable to be the major design criterion. In this dissertation, the vibration velocity was adopted as the major design parameter, which makes the design of the piezoelectric transformer becomes easier and clearer compared to the typical design rule. The proposed design procedure can predict the temperature rise as well as the losses of the piezoelectric transformers clearly. Both cold cathode fluorescent lamp based inverters and DC/DC converters can be designed to fit the requirements and the specifications well by the proposed design rule. The 32 inches LCDTV inverter and 10Watt DC/DC converter were fully developed successfully based on the proposed design procedure. In addition, although the piezoelectric transformer itself does not have to radiated EMI problem, it owns the conducted EMI problem. According to effect of the parasitic capacitor and the connected rectifier of the piezoelectric transformers, the EMI behaviour of the piezoelectric transformers based converter is quite different from the typical converters. The model and analysis of the EMI were detail in this dissertation. On the other hand, the piezoelectric layer fed rectifier is a non-linear device, which is not easy to analyze in general. The concept of the work cycle was proposed to simplify the analysis and the design. Based on the work cycle, the velocity controlled piezoelectric layer fed rectifier was proposed to optimize the energy flow of the piezoelectric layer. This technique was also applied to the structural damping, which can suppress the structure vibration effectively.

並列關鍵字

piezoelectric transformer ； switching power supply ； resonant power supply ； switching damping ； smart structure

參考文獻

[2] G. Ivensky, I. Zafrany, and S. Ben-Yaakov, “Generic operational characteristics of piezoelectric transformers,” IEEE Transactions on Power Electronics, vol. 17, no. 6, pp. 1049-1057, 2002.

[3] Y. H. Hsu, C. K. Lee, and W. H. Hsiao, “Optimizing piezoelectric transformer for maximum power transfer,” Smart Materials & Structures, vol. 12, no. 3, pp. 373-383, 2003.

[4] K. Uchino, and S. Hirose, “Loss mechanisms in piezoelectrics: How to measure different losses separately,” IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, vol. 48, no. 1, pp. 307-321, Jan, 2001.

[5] K. Uchino, J. H. Zheng, Y. H. Chen et al., “Loss mechanisms and high power piezoelectrics,” Journal of Materials Science, vol. 41, no. 1, pp. 217-228, Jan, 2006.

[7] Y. T. Huang, C. K. Lee, and W. J. Wu, “High-powered backlight inverter for LCD-TVs using piezoelectric transformers,” Journal of Intelligent Material Systems and Structures, vol. 18, no. 6, pp. 601-609, 2007.