應用於壓電元件能量擷取之適應型切換電容式降壓直流轉換器的設計與實作

Design and Implementation of Adaptive Switched-Capacitor Step-Down DC-DC Converter for Piezoelectric Energy Harvesting

王峻鴻(Chun-Hung Wang)

指導教授 ： 張原豪

朝陽科技大學/資訊學院/資訊工程系/碩士(2014年)

摘要

本篇提出閉迴路適應型切換電容式降壓直流轉換器(Closed-Loop Adaptive Switched-Capacitor Step-Down DC-DC Converter, ASCC)設計與實作，結合相位產生器和非重疊電路去實現以切換電容式(Switched-Capacitor, SC)降壓轉換器為主體的壓電能源採集系統。在閉迴路適應型切換電容式降壓直流轉換器的電力轉換電路中包含兩個子電路區塊：(i)前級電路：橋式整流器和輸入濾波電容(Ci)，(ii)主要級電路：五階段串並聯切換電容式降壓轉換器和輸出濾波電容(Co)。藉由使用前級電路的橋式整流器，可將壓電材料產生的AC電源轉換為DC電源，並將能量儲存至輸入濾波電容作為DC供應電源Vs；而主要級電路的五階段串並聯切換電容式轉換器可提供五個不同的降壓電壓( V_s/5,V_s/4,V_s/3,V_s/2,V_s)，並藉由相位產生器的運作，提供適應性充電工作階段(由最低電壓到最高電壓)以達到保護電池負載的目的。最後，此篇閉迴路ASCC的設計經由OrCAD Pspice設計並模擬幾個例子：不同電壓值的穩態輸出狀態、電源變動對輸出電壓的影響和負載變動時轉換器的調解能力，最後實現實作電路，所有結果皆可說明本篇所提出方法的效能。

關鍵字

降壓轉換器 ； 切換電容式(SC) ； 採集系統 ； 壓電材料 ； 適應性 ； 串並聯式

並列摘要

A closed-loop scheme of adaptive switched-capacitor converter (ASCC) is presented by combining a phase generator and non-overlapping circuit to realize the switched-capacitor-based (SC) step-down conversion for piezoelectric energy harvesting. In the power part of ASCC, there are two cascaded sub-circuits including: (i) Front: the bridge rectifier and a filter capacitor (Ci), and (ii) Core: 5-stage serial-parallel SC step-down converter and an output capacitor (Co). By using the front bridge rectifier, it converters the AC source of piezoelectric device into the DC source, and then harvests the energy to store in the filter capacitor Ci for building the DC supply Vs. The core 5-stage serial-parallel SC converter can provide 5 different step-down voltages (V_s/5,V_s/4,V_s/3,V_s/2,V_s), and with the help of the phase generator, perform an adaptive charging operation stage by stage (from the lower voltage to the higher one) for the protection of the battery load. Finally, the closed-loop ASCC is designed by OrCAD Pspice, and simulated for some cases: steady-state and dynamic responses (source/loading variation). Finally, we realize the implemental circuit, and all results are illustrated to show the efficacy of the proposed scheme.

並列關鍵字

Step-down converter ； Switched-Capacitor ； Harvesting ； Piezoelectric ； Adaptive ； Serial-parallel

參考文獻

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