《电涡流传感器位移特性实验报告分析.docx》由会员分享,可在线阅读,更多相关《电涡流传感器位移特性实验报告分析.docx(12页珍藏版)》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、电涡流传感器位移特性试验试验报告专业:机械工程班级:机械 7 班学号:2202307003姓名:牛嘉彬2023 年 11 月 20 日一前言位移传感器又称为线性传感器,是一种属于金属感应的线件,传感器的作用是把各种被 测物理量转换为电量。在生产过程中,位移的测量一般分为测量实物尺寸和机械位移两种。按被测变量变换的形式不同,位移传感器可分为模拟式和数字式两种。模拟式又可分为物性 型和构造型两种。常用位移传感器以模拟式构造型居多,包括电位器式位移传感器、电感式 位移传感器、自整角机、电容式位移传感器、电涡流式位移传感器、霍尔式位移传感器等。数字式位移传感器的一个重要优点是便于将信号直接送入计算机系
2、统。这种传感器进展迅 速,应用日益广泛。电涡流传感器能静态和动态地非接触、高线性度、高区分力地测量被测金属导体距探头 外表距离。作为一种非接触的线性化计量工具,它能准确测量被测体必需是金属导体与探头端面之间静态和动态的相对位移变化。在高速旋转机械和往复式运动机械状态分析,振 动争论、分析测量中,对非接触的高精度振动、位移信号,能连续准确地采集到转子振动状态的多种参数。如轴的径向振动、振幅以及轴向位置。电涡流传感器以其长期工作牢靠性好、测量范围宽、灵敏度高、区分率高等优点,在大型旋转机械状态的在线监测与故障诊断中得到广泛应用。因此我们需要来了解电涡流传感器的相关特性。长度是测量中最常见的物理量之
3、一,我们常常要通过推断物体的位移量来推断物体的状 态变化。除此之外,不少非位移变化量也是通过传感器内部器件相对位移来测量计算得出的。二试验目的了解电涡流传感器测量位移的工作原理和特性。三电涡流传感器的工作原理电涡流式传感器是一种建立在涡流效应原理上的传感器。电涡流式传感器由传感器线圈 和被测物体导电体金属涡流片组成,如图1 所示。依据电磁感应原理,当传感器线圈一个扁平线圈通以交变电流频率较高,一般为 1MHz2MHzI1 时,线圈四周空间会产生交变磁场 H1,当线圈平面靠近某一导风光时,由于线圈磁通链穿过导体,使导体的外表层感应出呈旋涡状自行闭合的电流I2,而 I2 所形成的磁通链又穿过传感器
4、线圈,这样线圈与涡流“线圈”形成了有肯定耦合的互感,最终原线圈反响一等效电感,从而导致传感器线圈的阻抗 Z 发生变化。我们可以把被测导体上形成的电涡等效成一个短路环,这样就可得到如图 1 的等效电路。图中R1、L1 为传感器线图 1 电涡流传感器原理图图.2 电涡流传感器等效电路图圈的电阻和电感。短路环可以认为是一匝短路线圈,其电阻为R2、电感为 L2。线圈与导体间存在一个互感M,它随线圈与导体间距的减小而增大。依据等效电路可列出电路方程组:通过解方程组,可得I1、I2。因此传感器线圈的复阻抗为:线圈的等效电感为:线圈的等效Q 值为:QQ01-(2 22)/(122)1+(R2 22)/( R
5、122)式中:Q0 无涡流影响下线圈的值,Q0 1R1;22 金属导体中产生电涡流局部的阻抗,22R22+ 2L22。由式 Z、L 和式可以看出,线圈与金属导体系统的阻抗Z、电感 L 和品质因数值都是该系统互感系数平方的函数,而从麦克斯韦互感系数的根本公式动身,可得互感系数是线 圈与金属导体间距离x(H)的非线性函数。因此Z、L、均是的非线性函数。虽然它整个 函数是一非线性的,其函数特征为“S“型曲线,但可以选取它近似为线性的一段。其实 Z、L、的变化与导体的电导率、磁导率、几何外形、线圈的几何参数、鼓励电流频率以及线圈到 被测导体间的距离有关。假设掌握上述参数中的一个参数转变,而其余参数不变
6、,则阻抗就 成为这个变化参数的单值函数。当电涡流线圈、金属涡流片以及鼓励源确定后,并保持环境 温度不变,则只与距离x 有关。于此,通过传感器的调理电路前置器处理,将线圈阻抗Z、L、的变化转化成电压或电流的变化输出。输出信号的大小随探头到被测体外表之间的 间距而变化,电涡流传感器就是依据这一原理实现对金属物体的位移、振动等参数的测量。为实现电涡流位移测量,必需有一个专用的测量电路。这一测量电路称之为前置器, 也称电涡流变换器应包括具有肯定频率的稳定的震荡器和一个检波电路等。电涡流传感器 位移测量试验框图如图 3 所示:图 3 电涡流位移特性试验框图依据电涡流传感器的根本原理,将传感器与被测体间的
7、距离变换为传感器的Q 值、等效阻抗 Z 和等效电感L 三个参数,用相应的测量电路前置器来测量。本试验的涡流变换器为变频调幅式测量电路,电路原理与面板如图4 所示。图 4 电涡流变换器原理图与面板图电路组成:Q1、C1、C2、C3 组成电容三点式振荡器,产生频率为1MHz 左右的正弦载波信号。电涡流传感器接在振荡回路中,传感器线圈是振荡回路的一个电感元件。振荡器作 用是将位移变化引起的振荡回路的Q 值变化转换成高频载波信号的幅值变化。D1、C5、L2、C6 组成了由二极管和LC 形成的形滤波的检波器。检波器的作用是将高频调幅信号中传感器检测到的低频信号取出来。Q2 组成射极跟随器。射极跟随器的作
8、用是输入、输出匹配以获得尽可能大的不失真输出的幅度值。电涡流传感器是通过传感器端部线圈与被测物体导电体间的间隙变化来测物体的振动相对位移量和静位移的,它与被测物之间没有直接的机械接触,具有很宽的使用频率范围从 010Hz。当无被测导体时,振荡器回路谐振于 f0,传感器端部线圈 Q0 为定值且最高,对应的检波输出电压Vo 最大。当被测导体接近传感器线圈时,线圈Q 值发生变,振荡器的谐振频率发生变化,谐振曲线变得平坦,检波出的幅值Vo 变小。Vo 变化反映了位移的变化。电涡流传感器在位移、振动、转速、探伤、厚度测量上得到应用。四试验预备器材机头中的振动台、测微头、电涡流传感器、被测体(铁圆片);显
9、示面板中的 FV 表或电压表;调理电路面板传感器输出单元中的电涡流、调理电路面板中的涡流变换器五试验步骤1、调整测微头初始位置的刻度值为 5mm 处,松开电涡流传感器的安装轴套紧固螺钉, 调整电涡流传感器高度与电涡流检测片相帖时拧紧轴套紧固螺钉并按图5 示意接线。图 5 电涡流传感器位移特性试验接线示意图2、将电压表FV 表量程切换开关切换到 20V 档,检查接线无误后合上主、副电源开关在涡流变换器输入端可接示波器观测振荡波形,登记电压表读数,然后逆时针调整测微头微分筒每隔 0.1mm 读一个数,直到输出Vo 变化很小为止并将数据列入表 1表 1 电涡流传感器位移 X 与输出电压数据Xmm7.
10、27.17.06.96.86.76.66.56.46.3Vo(V)0-0.24-0.37-0.52-0.69-0.79-0.95-1.05-1.18-1.33Vo(V)0-0.24-0.37-0.53-0.68-0.79-0.97-1.06-1.20-1.33依据表 1 数据作出VX 试验曲线。在试验曲线上截取线性较好的区域作为传感器的位移量程计算灵敏度和线性度可用最小二乘法或其它拟合直线。试验完毕,关闭全部电源。六数据分析Matlab 使用GUI 编辑m 文件如下:function varargout = nihe_gui(varargin)%NIHE_GUI M-file for nihe
11、_gui.fig%NIHE_GUI,by itself, creates a new NIHE_GUI or raises the existing%singleton*.%H= NIHE_GUI returns the handle to a new NIHE_GUI or the handle to%the existing singleton*.%NIHE_GUI(”Property”,”Value”,.)creates a new NIHE_GUI using the%givenproperty value pairs. Unrecognized properties are pass
12、ed via%varargin to nihe_gui_OpeningFcn. This calling syntax produces a%warning when there is an existing singleton*.%NIHE_GUI(”CALLBACK”) and NIHE_GUI(”CALLBACK”,hObject,.) callthe%local function named CALLBACK in NIHE_GUI.M with the given input%arguments.%*See GUI Options on GUIDE”s Tools menu. Cho
13、ose “GUI allows only one%instance to run (singleton)“.% See also: GUIDE, GUIDATA, GUIHANDLES% Edit the above text to modify the response to help nihe_gui% Last Modified by GUIDE v2.5 14-Dec-2023 19:05:47% Begin initialization code - DO NOT EDIT gui_Singleton = 1;gui_State = struct(”gui_Name”,mfilena
14、me,.”gui_Singleton”, gui_Singleton, . ”gui_OpeningFcn”, nihe_gui_OpeningFcn, . ”gui_OutputFcn”, nihe_gui_OutputFcn, . ”gui_LayoutFcn”, , .”gui_Callback”,);if nargin & ischar(varargin1) gui_State.gui_Callback = str2func(varargin1);endif nargoutvarargout1:nargout = gui_mainfcn(gui_State, varargin:);el
15、segui_mainfcn(gui_State, varargin:);end% End initialization code - DO NOT EDIT% - Executes just before nihe_gui is made visible.function nihe_gui_OpeningFcn(hObject, eventdata, handles, varargin)% This function has no output args, see OutputFcn.% hObjecthandle to figure% eventdata reserved - to be d
16、efined in a future version of MATLAB% handlesstructure with handles and user data (see GUIDATA)% vararginunrecognized PropertyName/PropertyValue pairs from the%command line (see VARARGIN)% Choose default command line output for nihe_gui handles.output = hObject;% Update handles structure guidata(hOb
17、ject, handles);% UIWAIT makes nihe_gui wait for user response (see UIRESUME)% uiwait(handles.figure1);% - Outputs from this function are returned to the command line. function varargout = nihe_gui_OutputFcn(hObject, eventdata, handles)%varargoutcell array for returning output args(see VARARGOUT);%hO
18、bjecthandle to figure%eventdatareserved - to be defined in a futureversion of MATLAB%handlesstructure with handles and user data(see GUIDATA)% Get default command line output from handles structure varargout1 = handles.output;function edit1_Callback(hObject, eventdata, handles)%hObjecthandle to edit
19、1 (see GCBO)%eventdatareserved - to be defined in a future version of MATLAB%handlesstructure with handles and user data (see GUIDATA)% Hints: get(hObject,”String”) returns contents of edit1 as text%str2double(get(hObject,”String”) returns contents of edit1 as a double% - Executes during object crea
20、tion, after setting all properties. function edit1_CreateFcn(hObject, eventdata, handles)% hObjecthandle to edit1 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesempty- handles not created until after all CreateFcns called% Hint: edit controls usually have a whit
21、e background on Windows.%See ISPC and COMPUTER.if ispc & isequal(get(hObject,”BackgroundColor”), get(0,”defaultUicontrolBackgroundColor”)set(hObject,”BackgroundColor”,”white”);endfunction edit2_Callback(hObject, eventdata, handles)%hObjecthandle to edit2 (see GCBO)%eventdatareserved - to be defined
22、in a future version of MATLAB%handlesstructure with handles and user data (see GUIDATA)%aHints: get(hObject,”String”) returns contents of edit2 as text str2double(get(hObject,”String”) returns contents of edit2doubleas% - Executes during object creation, after setting all properties. function edit2_
23、CreateFcn(hObject, eventdata, handles)% hObjecthandle to edit2 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesempty- handles not created until after all CreateFcns called% Hint: edit controls usually have a white background on Windows.%See ISPC and COMPUTER.if i
24、spc & isequal(get(hObject,”BackgroundColor”), get(0,”defaultUicontrolBackgroundColor”)set(hObject,”BackgroundColor”,”white”);end% - Executes on button press in pushbutton1.function pushbutton1_Callback(hObject, eventdata, handles)% hObjecthandle to pushbutton1 (see GCBO)% eventdata reserved - to be
25、defined in a future version of MATLAB% handlesstructure with handles and user data (see GUIDATA) x=str2num(get(handles.edit1,”string”); y=str2num(get(handles.edit2,”string”);p=polyfit(x,y,1); x1=max(x):-0.1:min(x); y2=polyval(p,x1); axes(handles.axes1) plot(x,y,”*r”,x1,y2);% - Executes on button pre
26、ss in pushbutton2.function pushbutton2_Callback(hObject, eventdata, handles)% hObjecthandle to pushbutton2 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesstructure with handles and user data (see GUIDATA) x=str2num(get(handles.edit1,”string”); y=str2num(get(hand
27、les.edit2,”string”);p=polyfit(x,y,1); x1=max(x):-0.1:min(x); y2=polyval(p,x1); e=abs(y-y2); axes(handles.axes1) plot(x,e);% - Executes on button press in pushbutton3.function pushbutton3_Callback(hObject, eventdata, handles)% hObjecthandle to pushbutton3 (see GCBO)% eventdata reserved - to be define
28、d in a future version of MATLAB% handlesstructure with handles and user data (see GUIDATA) x=str2num(get(handles.edit1,”string”); y=str2num(get(handles.edit2,”string”); y1=str2num(get(handles.edit3,”string”);e2=abs(y-y1); x1=max(x):-0.1:min(x); axes(handles.axes1) plot(x,e2);% - Executes on button p
29、ress in pushbutton4.function pushbutton4_Callback(hObject, eventdata, handles)% hObjecthandle to pushbutton4 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesstructure with handles and user data (see GUIDATA) close;function edit3_Callback(hObject, eventdata, handl
30、es)%hObjecthandle to edit3 (see GCBO)%eventdatareserved - to be defined in a future version of MATLAB%handlesstructure with handles and user data (see GUIDATA)%aHints: get(hObject,”String”) returns contents of edit3 as text str2double(get(hObject,”String”) returns contents of edit3doubleas% - Execut
31、es during object creation, after setting all properties. function edit3_CreateFcn(hObject, eventdata, handles)% hObjecthandle to edit3 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesempty- handles not created until after all CreateFcns called% Hint: edit control
32、s usually have a white background on Windows.%See ISPC and COMPUTER.if ispc & isequal(get(hObject,”BackgroundColor”), get(0,”defaultUicontrolBackgroundColor”)set(hObject,”BackgroundColor”,”white”);endfunction edit4_Callback(hObject, eventdata, handles)%hObjecthandle to edit3 (see GCBO)%eventdatarese
33、rved - to be defined in a future version of MATLAB%handlesstructure with handles and user data (see GUIDATA)% Hints: get(hObject,”String”) returns contents of edit3 as text%str2double(get(hObject,”String”) returns contents of edit3 as a double% - Executes during object creation, after setting all pr
34、operties. function edit4_CreateFcn(hObject, eventdata, handles)% hObjecthandle to edit3 (see GCBO)% eventdata reserved - to be defined in a future version of MATLAB% handlesempty- handles not created until after all CreateFcns called% Hint: edit controls usually have a white background on Windows.%S
35、ee ISPC and COMPUTER.if ispc & isequal(get(hObject,”BackgroundColor”), get(0,”defaultUicontrolBackgroundColor”)set(hObject,”BackgroundColor”,”white”);end用户图形界面为图 6用户交互界面输入数组后得出拟合函数 y=1.4145x-10.2602 拟合曲线如图 7图 7 试验数据拟合曲线图 8 线性误差曲线u- ux- xi +1ii +1i图 9 回程误差曲线确定误差呈现收敛的趋势,最大误差 =0.0775v 灵敏度s=0.1=1.33v/mm
36、线性度 = max/ Yx100%=0.0075/4.5x100%=1.72%七留意事项及总结测量之前电压表需要调零。量程与线性度、灵敏度、初始值均有关系。假设需要测量 5mm 的量程应使传感器在这个范围内线性度最好,灵敏度最高,这样才能保证其准确度。依据需要测量距离的大小,一般距离较大要求量程较大,且灵敏度要求不会太高,而且量程 有正负;相反需要测量的距离较小,则对灵敏度要求较高,量程不需要太大,这样既能满足要求,同时又保证了测量的准确度。在这次试验中我生疏了很多的传感器件,了解了各自的特性和使用状况,传感器的进展 是快速和影响深远的。伴随着自动化,电气化,信息化时代的到来,自动检测掌握系统的普及,传感器将承受材料、工艺,向智能化、集成化、多功能化方向进展。