具備最大轉換效率追蹤技術之寬操作範圍降壓轉換器

A Maximum Power Efficiency Tracking Technique for Wide Load Range Buck Converter

陳柏毅(Po-Yi Chen)

指導教授 ： 黃崇勛

國立中正大學/工學院/電機工程學系/碩士(2013年)

摘要

本論文針對目前既有的降壓型轉換器改善電源轉換效率的技術，研究其優缺點，並以寬負載操作範圍，高電源轉換效率為主軸來設計。目前降壓型轉換器的改善電源轉換效率的技術有變頻操作模式、混合控制模式和停滯時間控制模式三大方向。這些技術都必須於轉換器控制系統中，增加額外的選擇電路和切換機制，因此造成額外的功率消耗，使得電源轉換效率的提升有一定的極限。
綜合以上的討論，本論文選擇使用單一控制器的方法來設計降壓型轉換器的控制系統，並提出一個改善電源轉換效率的技術，稱為最大轉換效率追蹤機制(Maximum Power Efficiency Tracking Technique)，此機制打破了傳統的做法，不需要額外的選擇電路和切換機制，其控制概念很簡單，當轉換器負載需要能量，就給剛剛好的能量，不給過多也不給過少，依據負載端的需求自動調節責任週期和切換頻率，並監測控制系統電路區塊的消耗功率，一旦有不需要運作的電路區塊，即讓其進入截止狀態，因此能使降壓型轉換器在大負載操作範圍下依然維持高電源轉換效率。
最終使用台積電TSMC 0.18μm 1P6M 3.3V Mixed Signal製程製作實現，晶片面積大約1.04 x 1.03 mm2，使用創新架構最大轉換效率追蹤機制，該技術可在一個寬廣的負載操作範圍下，追蹤最大的電源轉換效率。最大轉換效率追蹤機制的平均效率大於65%，負載操作範圍可從1mA到500mA的區間。

關鍵字

最大轉換效率追蹤技術 ； 寬操作範圍 ； 高轉換效率 ； 降壓轉換器

並列摘要

In this thesis, existing buck converter to improve power conversion efficiency of technology is investigated to design wide load operative range and high power conversion efficiency. There are three major directions to improving power conversion efficiency of technology for existing buck converter, variable frequency operation mode, hybrid control mode, and dead time control mode. These techniques have to be added the selection circuit and switching mechanism in the control system of buck converter, which causing extra power consumption and limiting of enhancement power conversion efficiency.
Regarding the above discussion, this thesis selects a single control method to designed, and propose a novel control method which is a maximum power efficiency tracking technique. It is very different from traditional approach, needing no additional the selection circuit and switching mechanism, which control concept is very simple. When load of buck converter requires energy, it’s will give suitable energy, and depend on requirement of load adjusting the duty cycle and the switching frequency automatically, and monitoring power consumption of control circuit blocks, if there is no operation of the circuit blocks that let into dormant state, thus buck converter operates in the wide load range and maintains high power conversion efficiency.
Finally, this buck converter chip is designed and fabricated with TSMC 0.18μm 1P6M 3.3V Mixed Signal process technology. The chip area is about 1.04 x 1.03 mm2 and makes use of the novel technology of a maximum power efficiency tracking technique. This technology can operate in the wide load range, and track maximum power conversion efficiency. Maximum power efficiency tracking (MPET) technique has average efficiency over 65%, and operation from 1mA to 500mA of loading current.

並列關鍵字

Wide load range ； High power efficiency ； Buck converter ； Maximum power efficiency tracking technique

參考文獻

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