本論文旨在對整個電磁式流量計之基本設計流程做探討並予以試製。電磁式流量計是基於法拉第電磁感應定律以測量流體的流量。文中以低頻矩形波來驅動激磁線圈以產生磁場，且於測量管兩端之電極擷取其感應電動勢，並連接信號處理電路。此感應電壓經過放大器與濾波器的處理，且由取樣技術以克服來自激磁線圈電磁干擾的影響。最後，信號處理電路的輸出電壓顯示其與流量成正比的關係。由實驗結果顯示，此實際試製的電磁式流量計具有可靠的準確度。

This thesis aims at investigating the basic design procedure of electromagnetic flowmeters and trial-producing it. The electromagnetic flowmeter uses Faraday’s law of electromagnetic induction to measure the process flow. Low frequency and square wave voltage is applied to the excitation coil to generate the magnetic field. The EMF is picked up by electrodes that are arranged diametrically on the tube and connected to the signal processing circuit. The induced voltage is processed by amplifiers and filters. Sampling the amplified signal overcomes the magnetic interference induced from the excitation coil. Finally, the output voltage of the signal processing circuit is proportional to the flow rate. The experimental results show that the practically trial-produced electromagnetic flowmeter has good accuracy.

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