應用於再生能源之低電壓高效率電源積體電路

Abstract

近年環保意識的抬頭，讓可永續利用且少汙染的可再生能源受到各方矚目。太陽能電池 以及熱電產生器可將光能、熱能所產生的微小能量轉換成可利用之電能，提供電子產品 使用，以延長電池使用時間或實現無電池系統。太陽能電池及熱電產生器之輸出功率及 輸出電壓有限且隨著環境劇烈變化，因此低電壓且高轉換效率之電源積體電路成為應用 於再生能源電力轉換技術的關鍵技術。近年來各國雖已積極投入相關電路研發，但目前 仍無兼具低電壓及高轉換效率之電源積體電路。尤其當電源積體電路之負載為生醫感測 晶片或無線感測網路等的低功率系統時，改善其轉換效率具有相當大的挑戰性。本計畫 未來兩年的目標，在於開發可應用於再生能源之高效率直流-直流電壓轉換電路。主要 的工作為第一年: (1)建立低電壓啟動電路的系統架構; (2)研發低功率數位脈衝寬度調變 電路; (3) 局部升壓電路設計; (4)關鍵子電路之晶片製作及量測。第二年: (1) 研發低電壓 回授控制系統; (2)高效率驅動系統之開發; (3)晶片整合、晶片製作以及量測。預期本計 畫的執行成果將可與太陽能電池或熱電轉換產生器結合演示，以確定其有效性，並發表 於國際研討會與國際期刊。創新的研發成果也將申請專利，提供業界使用本計畫之研究 成果。

Recently, harvesting energy from the environment is on a great focus due to echo-conscious. The photovoltaic cells and thermoelectric generators (TEG) are possible to convert the light and thermal energy into electric power and supply the load circuits. This provides the solution for battery-free systems or increases the battery lifetime in consumer electronics. The output characteristics of these harvesters significantly depend on the environment and the generated power and voltage are limited. Therefore, a low-voltage high-efficiency power management unit (PMU) that can accommodate the harvested energy to usable outputs is of great importance. Until now, several converter architectures and circuit techniques have been reported to reduce the operation voltage. The conversion efficiency of these converters, however, is still limited. Especially in low power application, the improving the conversion efficiency in PMU is particularly a challenging task. The goal of this project is to develop the low-voltage high-efficiency PMU to effectively convert the collected energy to usable outputs. The planned tasks in the following two years are summarized as following. The first year: (1) Develop fully integrated startup architecture. (2) Design a low-power digital pulse width modulation circuit. (3) Design a local boost converter. (4) Tape-out and measure the key sub-circuits. The second year: (1) Develop a low-voltage low-power feedback controller. (2) Develop a high-efficiency driver system (3) Integrate the sub-circuits, tape-out and measurement. The goal of this project is to provide the solution for PMU in renewable energy. The circuit will combine with the energy harvester for the demonstration. The research results will also be presented in the international conference and published in the international journals. Patents will be applied in this project to provide the usage of this invention to the industry.