應用於電磁式獵能系統之自調整式無壓降電荷幫浦電路

Abstract

近年來隨著科技的進步，人們對於行動裝置上之功能以及各種微系統感測器的應用有越來越多的需求，但是儲能元件如電池等的進步卻無法跟上這些裝置上能源需求的腳步，對於能源的開源如利用獵能系統於環境中擷取能源，以及節流如電源管理電路之需求等綠能議題也逐漸發燒，許多系統設計者開始考慮使用獵能裝置作為能量之來源，以免除電池之更換或延長電池的使用時間。震動式能源為一容易取得之能量源，因此在本篇論文中，提出一電磁式獵能機構將環境中之振動能量透過此機構以電磁感應之方式轉換成可用之電能，並設計一自調整式無壓降充電幫浦以及後方的電能管理電路與穩壓器等介面電路，將微獵能器產生之微小交流式能量收集起來，轉換為可供電子裝置使用之直流能量儲存或直接對微系統供電。為了使能量的收集的更為有效率，本篇論文亦提出了專用於此整流充電幫浦之最佳化方法。本篇論文提出之微獵能電路，可將峰值大於0.7伏特之交流能量，轉換為3.3伏特之直流電源；除此之外，自調整式無壓降充電幫浦可根據我們提出之最佳化方法，在獵能機構之輸出改變時自動調整電荷幫浦之階數使系統轉換效率能維持高效能，而其無壓降之整流特性也降低能量傳遞其間之消耗，電能管理電路則可以根據監測負載裝置及獵能器之輸出電能狀況對能源傳輸進行有效控管。藉由本篇提出之最佳化方法，充電幫浦萃取的能量相對於最大能量有0.6%的誤差，而轉換至過渡電容時僅有0.73%之誤差。本篇論文所提出的電路，皆成功由台積電0.35微米製程模擬與實現。在文中，電路設計之概念與原理，以及實驗結果皆完整介紹與說明。

In the innovation technologies in recent years, there have been increasing demand in mobile devices and micro sensors systems. However, batteries progress cannot meet these devices energy needed. Solutions such as energy harvesting and power management become hot research topic today. A lot of system designer start considering on implementation of energy harvest devices to enlarge the batteries work time or to set a battery less system. Vibration energy is easy to be used and collected in common environment; therefore, in this thesis, a magnetic mechanical structure is proposed to transform environmental vibration energy to electrical energy. A self-adjustable dropless rectifier charge pump, a power management, and a low-dropout regulator are designed, transferring the AC energy produced by harvesters to the DC energy suitable for common electrical devices. For deriving high power transferring efficiency, the optimal method for the proposed rectifier charge pump is also proposed. The energy harvesting circuit proposed in this thesis can transfer the AC energy of which the peak voltage is more than 0.7V to the DC energy in a fashion of 3.3V; furthermore, self-adjustable dropless rectifier charge pump can control charge pump stages by the proposed optimal method to make system containing high efficiency. Charge pump’s dropless specification can also make energy loss low on transforming. The power management can avoid the abnormal operation when the input power is weak. By the proposed optimal method, 0.6% error occurs when the energy is extracted from harvesters (State 1), and 0.73% error occurs when the energy is transfer to the interface capacitor (State 2). The proposed circuit is simulated and fabricated via TSMC 0.35m process successfully. In the article, the concepts, operational principles, and experiment results are illustrated.