智慧型焦電獵能系統

Smart Pyroelectric Harvesting Systems

蔡易哲(Yi-Je Tsai)

指導教授 ： 蕭俊卿

國立虎尾科技大學/工程學院/機械設計工程系碩士班/碩士(2017年)

摘要

焦電元件為一種綠色獵能之新穎材料，由於焦電元件受到時變溫度率變化產生電能，經常被廣泛應用於廢熱能轉換為電能之處，其焦電元件時變溫度率受元件厚薄度影響，當較薄元件因熱容積小，能快速吸收熱能提升時變溫度率，適合於儲能前段時間；則較厚元件因熱容積大，吸收熱能較慢導致電性響應較為緩慢，適合於儲能後段時間，因此本研究設計一套智慧型焦電獵能系統，其具兩種不同厚度420μm及65μm之焦電元件並同時應用於獵能，透過LabVIEW圖形化程式控制繼電器作時序性控制並經由橋式電路儲存至4.7μF電容，由實驗結果得知，經元件優異電性整合後於升降溫週期為20秒時，於儲能時間前42%其電能量可達1×10-2毫焦耳(mJ)，相較於焦電元件具單一厚度420μm及65μm分別提升81%、856%，於儲能飽和後其電能量，相較於焦電元件具單一厚度420μm和65μm分別提升約56%和277%，因此可證明具厚度420μm之焦電獵能元件於儲能時適時協同具厚度65μm之焦電元件下，能有效提升儲能效率。

關鍵字

焦電獵能 ； 綠能科技 ； 噴砂蝕刻 ； 時變溫度率

並列摘要

The pyroelectric cell is a novel material for green energy harvesting. The pyroelectric effect has been used for solar energy or waste thermal harvesting to convert temporal temperature fluctuations into electrical energy to fully utilize abundantly available waste heat. A thicker pyroelectric cell with a larger thermal capacity is favorable when generating a higher induced voltage for a longer working period at a higher temperature. However, a thinner pyroelectric cell with a small thermal capacity is favorable when generating a higher induced charge per period for a shorter working period at a lower temperature. Hence, integrating a thicker with a thinner pyroelectric cell is attempted to try to extend applications and increase the efficiency of pyroelectric harvesters. In the present study, a smart system integrating two pyroelectric cells with various thicknesses of 420μm and 65μm is adopted to enhance the efficiency of pyroelectric cells by the software of NI LabVIEW to control relays in the sequence control for further storing the charge in a 4.7 μF electrolytic capacitor as a storage element. The results show that the smart system can store the electric energy to 1×10-2 mJ at 42% of storage time when using the working period of 20s. This outcome is higher than using alone the 420μm thick pyroelectric cell about 81%, and the 65μm thick pyroelectric cell about 856%. In the saturated state, the electrical energy generated by the smart system is higher than that of using alone the 420μm thick pyroelectric cell about 56%, and the 65μm thick pyroelectric cell about 277%. Hence, the smart system integrating two pyroelectric cells with various thicknesses of 420μm and 65μm is available to promote the efficiency of pyroelectric harvesters.

並列關鍵字

Pyroelectric harvesting ； Green energy ； Sandblasting ； Temperature variation rate

參考文獻

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