定溫型流量感測器之模型推導與電路分析

Abstract

在本論文中，我們分析了定溫型感測電路的運作原理，並建立了一個包含 電路運作與感測元件間熱交換的模型，並以控制理論來探討感測電路的動態特性。由此模型，可以了解定溫型感測電路的系統特性，並了解感測元件如何影響系統的響應。本論文並以工業研究院機械所提供之流量感測元件，實際設計電路來測試與驗證本論文所提出的模型，實驗結果與模型分析相當的符合。由本論文所建構的模型與實驗結果，可以明瞭感測元件設計所要注意的重要事項，並指出未來改善感測元件特性的方向。

In this thesis,we analyze the circuit operation of constant-temperature mass flow sensor and establish a model which can characterize heat transfer between the flow senosr circuit and sensor elements. The dynamical behavior of the flow sensor circuit is also investigated in term of the control theory. The result of model enable us to explain the system behavior of the constant-temperature flow sensor circuit and how the flow sensor element effects the response of the system.In the thesis we also design a circuit for a real flow sensor provided by Mechanical Industry Research(MIRL) of Industry Technology Research institute(ITRI) to verify our model. The experimentd result and simulation result of our presented model matches well.The developed model of the thesis is useful to explain the behavior of sensor circuit and improve the sensor design.