便攜式智能油氣檢測儀設計

摘 要:為了防備油氣濃度超標造成的安全事故，研制了便攜式智能油氣檢測儀。采用接觸燃燒式氣敏傳感器進行油氣檢測，并增加補償元件。用電橋電路作為測量電路，用雙端輸入方式連接電橋與運算放大器，對所采集的信號作放大、補償處理。采用集成電路A/D芯片進行信號A/D轉換，并在LCD數字顯示屏上顯示油氣濃度值。設計報警電路，用C++語言設計軟件，采用單片機進行系統控制。氣敏元件的誤差補償和數字化濃度檢測有創新。該檢測儀適用于石油、天燃汽等儲運和使用場所。關鍵詞:油氣; 智能檢測; 氣敏傳感器; 信號A/D轉換; 單片機

中圖分類號:TN919-34; TP216 文獻標識碼:A

文章編號:1004-373X(2010)18-0157-03

Design of Portable Smart Oil-gas Detector

ZHOU Yu-di

(College of Engineering， Hong Kong Polytechnic University， Hong Kong， China)

Abstract: For taking precautions against the safe accidents by reason of oil-gas whose consistency is over standard limit， the portable smart oil-gas detector is developed， and the contact combust-type gas sensitive sensor is adopted and a compensatory component is added to detect the oil-gas concentration. The bridge circuit is used as a measuring circuit and is connected with the operational amplifier in double-ended input mode. The detected signal is amplified and compensated. The integrated circuit A/D chip is used for signal A/D converting. The consistency value of oil gas is displayed in LCD digital monitor. The alarm circuit is designed. The software is programmed with C++. The system control is accomplished by single chip proce-ssor. It has innovation in error compensation of gas sensitive component and digital consistency detection. It is applicable for the places where oil and natural gas are stored， transported and used.Keywords: oil-gas; smart detection; gas sensitive sensor; signal A/D converting; single chip processor

0 引 言

隨著國民經濟高速發展，石油、天燃汽等能源在日常生活和化工等領域得到廣泛應用。在使用過程中，不可避免地存在著易燃、易爆油氣，油氣濃度超標極易釀成火災、爆炸和人員中毒等惡性事故。分析事故發生的主要原因是油氣濃度檢測設備技術落后，不能準確檢測出油氣濃度超標并及時報警。因此，研制性能可靠的便攜式智能油氣檢測儀是極為必要的。

1 設計思路

便攜式智能油氣檢測儀是一種應用傳感器、集成電路、單片機和計算機模式識別等技術而設計的儀器。采用接觸燃燒式氣敏傳感器進行油氣檢測，這種傳感器是經“國家防爆電氣產品質量監督檢驗測試中心”檢測認定達到國家防爆標準的密封吸入式防爆裝置，其穩定性和準確性好，檢測范圍較大。……