受到製程技術進步、全球景氣復甦及價格下滑，大尺寸液晶電視成為市場主流，但隨著環保與節能的議題日益受到重視，相關規範皆要求液晶電視的功耗愈來愈低。故創新電源供應的設計也將成為未來勝出的關鍵，如何兼顧成本低、體積小與轉換效率高，已成為相關設計人員所面臨的共通課題。
本篇論文主要目的是設計適用於大尺寸液晶電視的數位化電源，整體架構大致分為二個部分：前級使用交錯式臨界導通模式操作的功率因數修正電路作為前置調節器，以改善功率因數並減少輸入電流之總諧波失真。後級則應用相量轉換法推導出LLC串聯諧振轉換器小信號模型並設計補償器。最後再以Microchip dsPIC30F2020為數位控制核心，達成數位變頻控制、減少元件成本及提供更彈性的設計之目的。藉由數位方式實現PID控制器，完成液晶電視的數位化電源。實驗結果證明所提出系統之可行性。

Nowadays, liquid crystal display (LCD) panels are widely used in applications such as monitors, notebooks and televisions. In large scale LCD TV (>30”), the power supply is generally internal as it requires from 200 W to 600 W. Because the input power is above 75 W, the application has to be compliant with the IEC1000-3-2 class D standard. Therefore, power factor correction (PFC) is needed. In this thesis, the design of a digitalized power supply for large scale LCD TV is presented. The whole system consists of three major parts. An interleaved critical conduction mode (CRM) power factor corrector in front stage is employed as pre-regulator for improving the input power factor and reducing the total harmonic distortion. A half-bridge LLC resonant converter is utilized as the DC/DC conversion stage. The LLC resonant topology allows for zero voltage switching (ZVS) of the main switches, thereby dramatically lowering switching losses and boosting efficiency. Finally, the dsPIC30F2020 from Microchip corp. is used as the digital controller of the LLC resonant converter. In order to design the compensation circuit correctly, the large-signal and small-signal model of the utilized LLC converter is also derived in this thesis using the phasor transformation method. In order to verify the correctness of the proposed system, experimental results will be given to validate the correctness of the proposed system and the measured efficiency of the whole system achieved 82%.

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