| In industrial production,flow is a parameter which needs to be measured and controlled frequently,especially in process industry such as iron and steel industry;electric power industry,water supply industry and natural gas industry. Material flow now comes to be the guide line of production efficiency and economy. Thereby flow meter is widely applied.Nowadays,many domestic companies are still using the flow meter with low precision and out-of-date computing model.Many of them usually adopt fore-and-back ground single loop structure design,which cannot meet the requirement of real-time performance,reliability and portability.As this situation,this thesis first discusses the basic concepts of flow measuring, and then introduces a design of intelligent general flow meter supports field bus communication and feedback control,which adopts Freescale MC68HC908AZ60 microcontroller and FDCX08 RTOS.The meter has following features:1.Supports three types of mediums(including steam,gas and liquid) and sensors.Using MATLAB as modeling tool,fast algorithms with high-precision have been devised for every type of mediums and sensors.For steam,we use IAPWS-IF97 formula,which has the highest precision.2.Because of the multi-task scheduling and modularize design,the real-time performance,reliability and stability of the system are greatly improved.3.Supports field bus communication and feedback control;the meter can be used as a field node of industrial distributed control system.The thesis mainly composed of three parts:Part 1;discuss the basic concepts of flow measuring;Part 2;introduce the goal of the project.Part 3;introduce the implement of the flow meter. |
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