Development of virtual instrument motor experiment teaching system based on LabVIEW

Transcription

1 Avalable onlne Journal of Chemcal and Pharmaceutcal Research, 204, 6(5): Research Artcle ISSN : CODEN(USA) : JCPRC5 Development of vrtual nstrument motor experment teachng system based on LabVIEW Zongjan Huang and Xngju Wang Department of Archtectural Envronment Equpment Engneerng, Henan Polytechnc Insttute, Henan Nanyang, Chna ABSTRACT The hardware platform of the vrtual nstrument conssts of PC computer and data acquston card (DAQ card). In ths paper, vrtual nstrument technology s appled to the motor teachng laboratory constructon. The DAQ system conssts of sensors, sgnal condtonng crcuts, data acquston card, computer whch s composed of the hardware, the sgnal condtonng crcut and data acquston card. The paper proposes development of Vrtual Instrument Motor Experment Teachng System based on LabVIEW. Ths paper uses the LabVIEW software as a development platform, usng exstng equpment condtons of the laboratory to desgn a motor speed control system, the control of motor speed, the expermental results wth hgh precson and effcency. Keywords: Vrtual nstrument, LabVIEW, Motor, Teachng System. INTRODUCTION LabVlEW s the applcaton software of vrtual nstrument developng an open system, t provdes a convenent, easy desgn envronment for desgners, desgners can use t just as buldng blocks, easy to set up a measurement system and data acquston system, and arbtrary structure nstrument panel on ts own, wthout wrtng any tedous the computer program code, whch can smplfy program desgn. Automatc detecton system of motor based on tradtonal development platform, often faces long development cycle, hgh cost, compatblty and expansblty of the weak, and thus hnders the wde applcaton of automatc motor testng system []. Now the applcaton of vrtual nstrument software by computer and standardzaton of vrtual nstrument hardware together, realze the software and module functon of tradtonal nstrument, n order to acheve the purpose of automatc detecton and analyss. The user can through the technology of vrtual nstrument graphcal programmng envronment and operaton nterface, easy to measure the sgnal condtonng, object of process control, data acquston, analyss, dsplay and storage functons, greatly shorten the system development cycle; at the same tme as the vrtual nstrument software and hardware usng a standardzed test, the compatblty of the system and scalablty s mproved greatly. Teachng, scentfc research requres a lot of measurement and analyss nstruments, especally n expermental teachng, each nstrument must be confgured wth multple sets, and some equpment s expensve, so the equpment requred for the huge nvestment, t s dffcult to meet the general school, caused many schools lack of outdated equpment and other phenomena, serously affects the teachng scentfc research. If the use of vrtual nstrument system, t s not the same. Put nto use vrtual nstrument not only can save a lot of equpment funds, but also can mprove the qualty and effcency of teachng and scentfc research. The use of exstng computer vrtual nstrument, specal desgn wth hardware and software, formng the basc 36

2 functon of both ordnary nstrument, and t s upscale low prce new nstrument and the common nstrument no specal functon. Vrtual nstrument s a new mode of the nstrument of computer technology and electronc nstrument whch combnes. It s usually composed of a personal computer, the functon of hardware module and used for data analyss, process communcaton and graphcal user nterface applcaton software combnaton, the computer has become a measurement functon of dgtal measurement platform. It uses the software to generate a varety of nstrument panel on the screen, complete the processng, transmsson, storage, dsplay, expresson and functon of data. The paper proposes development of Vrtual Instrument Motor Experment Teachng System based on LabVIEW.. Desgn of Vrtual Instrument LabVIEW All LabVlEW applcatons, vrtual nstrument, whch comprses a front panel (front panel), and t s flow chart (block dagram) and the con and connector (con/connector) three. The front panel s a graphcal user nterface; vrtual nstrument panel s the VI, the nterface wth the user nput and dsplay output of two objects, specfc performance of swtch, knob, graphcs and other control (Contr0) and dsplay object (ndcator). LabVIEW s an end-user tool. It can enhance your ablty to buld ther own scentfc and engneerng system, provdes a convenent way to nstrument programmng and data acquston system [2]. Prncple of usng t for research, desgn, test and mplement nstrumentaton systems, t s can greatly mprove work effcency. The work of the LabVIEW panel s as shown n fgure. Fg.. The work of the LabVIEW panel The work of LabVIEW nterface. Each of the VI prepared by LabVIEW s composed of a front panel, block dagram, con / connectng port three. The front panel language settngs and observng the output nput, smulate the real nstrument used for front panel. On the front panel, nput referred to as control (Controls), output s called the show (Indcators). Control and dsplay s to form varous cons appear on the front panel, such as knobs, swtches, buttons, charts, graphcs etc.. Accordng to the dfferent condtons usng the I/O nterface to hardware devces of dfferent, such as the data acquston card (DAQ), GPIB bus, VXI bus nstrument nstrument module, seral nstrument, there are fve types of vrtual nstrument structure. LabVIEW provdes a varety of graphcs drver, the user does not need to be famlar wth PCI bus, GPIB bus, VXI bus, seral bus, I/O nterface equpment provded by the use of LabVIEW graphcs drver can drve the bus, the measured sgnal nput, data acquston, amplfcaton and analog / dgtal converson, and then for the computer for further processng. Although there are great dfferences between the fve systems, but no matter what knd of VI system, s through the applcaton of software and computer hardware combnaton. GPIB (General Purpose Interface Bus) consttute the nstrument system s the frst step towards the vrtual nstrument, whch uses the GPIB nterface card to connect a pluralty of GPIB nstrument, usng the computer to enhance the functons of tradtonal nstruments, organzaton of large-scale flexble automatc test system, easy upgrade, easy mantenance, nstrument panel functons and custom, the development and use of easy. It can be acheved effectvely test and measurement task of varous scales. Usng GPIB technology, whch t can be realzed by the computer operaton and control of the nstrument, to replace the tradtonal manual mode of operaton, test and measurement errors caused by human factors of excluson. At the same tme, because of the prepared test procedures, to acheve automatc test, mproved the test effcency. LabVlEW has a pluralty of graphcal operaton template, used to create and run the program. These templates can 362

3 be moved on the screen at random, and can be placed at any locaton on the screen. There are three types of template, template tool (Tools), control (controls) and functon (Functons) template. The tool template (Tools Palette) provdes varous used to create, modfy and debug VI program tool for programmers, when the template choose any knd of tool, the mouse arrow wll become the shape of the correspondng tools. Control template (Controls Palette) can add nput control and output dsplay as a front panel. Functon template (Functons Palette) s to create the block dagram tool. LabVIEW software platform s the central nervous system, whch makes the whole measurement system become an organc whole ntellgent, n software guded automatc sgnal acquston and storage accordng to the prescrbed procedures, automatc operaton data analyss and processng, n an approprate form output, dsplay or record the measurement results. For the constructon of vrtual nstrument, LabVIEW has many characterstcs and advantages, such as: graphcal programmng nstrument control and data acquston; ntutve front panel user nterface and workflow schema programmng style; the bult-n compler can accelerate the speed of executon; the data acquston of DAQ functon lbrary allows users to collect sgnal or a control sgnal, sutable for applcaton to control the rapd and drect; the drver can drve 650 knds of nstruments, equpment more than 50 manufacturers; advanced analyss lbrary content rch, sgnal processng, statstcs, curve fttng and complex analyss; usng Actvex, DDE and TCP/IP network connecton and communcaton process for Wndows NT/9X/XP; MacOS, HP2UX, Sun, and Concurrent real-tme computer. Vrtual nstrument software archtecture (VISA -- Vrtual Instruments Software Archtecture) s desgned to mprove the effcency by reducng the system tme. Wth the nstrument type and the ncreasng complexty of test system to mprove, people don't want to wrte a dfferent program for each knd of hardware nterface, the I/O nterface ndependence for I/O control software s becomng crucal. Through the VISA user can connect wth the majorty of nstrument bus, ncludng GPIB, USB, seral port, PXI, VXI and ethernet. Regardless of the underlyng the hardware nterface and t s the user only needs to face the programmng -- a unfed VISA nterface, as s shown by fgure2. Fg. 2. The Structure of Vrtual nstrument software archtecture RS-232 bus s a unversal seral bus uses most early, the more PC used the USB bus and IEEE 394 bus. Unversal seral bus (Unversal Seral BUS, USB) has the advantages of hgh transmsson speed, support asynchronous and sochronous transmsson characterstcs, sutable for data transmsson stuaton relatvely hgh n the large amount of data, data transmsson rate requrements. System of seral port and other ndustry based on standard bus connects some seral port equpment and ndustral control module, real-tme montorng system. No matter what knd of vrtual nstrument system, the nstrument s equpped wth the notebook computer hardware, computer or workstaton and varous computer platforms, coupled wth the applcaton software. Usng LabVIEW software, you can buld a vrtual nstrument nstead of programmng. A software system for nteractve control, users can easly buld the front panel wndow. In order to acheve a specfc functon, the user to flow chart together usng the wzard [3]. A front panel: select the object you need from the control board, the front panel on the vrtual nstrument. The control object template ncludes a dgtal dsplay meter, pressure meter, thermal meter, shell, tables, pctures etc.. When your vrtual nstrument, vrtual nstrument can work n ten usng the front panel to control the whole system, such as the movement of the sldng plate, n the mage to the nput from the 363

4 keyboard, etc. The powerful functon of LabVIEW n the herarchcal structure, users can create VI program as a subroutne call, to create more complex programs, and, callng the order can be arbtrary. Methods LabVIEW that create and call the subroutne to create program modular, easy to debug, understand and mantan. Dfferent method of program desgn LabVIEW programmng wth the tradtonal method, t has the flow chart of program desgn language, get rd of the shackles of the tradtonal program language lnear structure. The order of executon n accordance wth the block dagram of LabVIEW data flow between decsons, and t s unlke the general programmng language progressve mplementaton. In the preparaton of block dagram program, only need to use a dfferent functon con from functon module, then the lnes are connected to each other, can realze data transmsson. Publshed n the WEB LABVIEW program n a varety of ways, but must use each way before the frst open Web server n the release program computer. LABVIEW web server default settngs can meet the needs of the general program. That s to say as long as the open web server, not for any of the settngs, you can complete the general task. The drver module of each nstrument has ts own nstrument. The essence of nstrument drver s provded for operatng functon more abstract operatng nstrument set for the user. For the applcaton, the operaton of the nstrument s realzed through the nstrument drver; nstrument drver for the operaton and management of the nstrument, and s the unty based and format provded by I/O software lbrary (VISA) calls to acheve. For applcaton desgners, as soon as the nstrument drver, n the not very understand the process nstruments nsde the case, the desgn work can also be carred out n vrtual nstrument system. The vrtual nstrument drver s the brdge and lgament between the applcaton and the underlyng I / O nterface software. A data acquston system s based on vrtual nstrument [4]. Ths way by means of the nsert n the computer data acquston card and specal software such as LabVIEW (LabWndows / CVI) combned wth A/D converter, analog, dgtal sgnal acquston to the computer for analyss, processng, dsplay, and through the D/A converson to realze feedback control. A sophstcated data flow programmng model lberated users to construct the program from the lnear text language approach usng LabVlEW. Because the executon sequence program n LabVlEW software flow are decded by each block of data. You can also set up the flow chart of synchronous operaton. LabVlEW software s a mult thread functons of a mult task system -- wth and run multple vrtual nstruments. 2. Research on Vrtual Instrument Motor Experment Teachng System The frequency test sgnal of the system requred s very hgh, accordng to the requrements of the samplng theorem, the requred A / D must be hgh, reflectng the hgh speed data acquston system that the data can be compared to the real measured sgnals. But wth the samplng rate of ADC devces ncreases, ts prce s also more expensve, so the choce of ADC devces must be weghed aganst ts performance prce rato. In addton, from the current commonly used nstrument - measurng sgnal osclloscope, sgnal measurement system must have at least two sgnal channels, detecton can at the same tme sgnals, so as to observe, compare the relatonshp between two sgnals [5]. It has two knds of acquston optons, whch s one of the two channels usng swtch, turns nto the sngle channel A / D acquston. However, ths alternate mode s sure to lose part of nformaton, after all, two not smultaneously acquston, t can not be accurate to the observaton of the relatonshp between the sgnals. Measurement of three phase crcut power. A three-phase crcut, connecton mode load are star connecton and a delta connecton. Star connecton, accordng to the needs of the three-phase three wres or four wre three-phase power supples, trangular connecton can be used only when the three-phase three wre power supply. Three-phase four wre crcut, the total power consumpton load requred power were measured A, B, C load of each phase, and then add. That s equaton (). P + P 2 = u = ( u = u AC A A A A u + u C + u BC B ) A B B + ( u u B C A u C u ) B C B () The more dgts ADC, resoluton s hgher, can be dstngushed n the smaller voltage. For example, the three bt converson the analog voltage range s dvded nto segments, each segment wth bnary codes n the range 000 to l sad. Therefore, the dgtal sgnal can not reflect the orgnal sgnal, because some nformaton s mssng. If ncreased to thrteen, the code number ncreased from 8 to 892, the dgtal nformaton so that you can more accurately reflect the orgnal sgnal. 364

5 The modular desgn of the LabVIEW vrtual nstrument, so any vrtual nstrument can run ndependently, but also can be used as a part of other vrtual nstrument. You can even create vrtual nstrument con of ther owns, and t s as to desgn mult-layer system composed of vrtual nstrument, and can change t, exchange wth other vrtual nstrument and connected to meet the need of changng applcaton. LabVIEW development of the VI program, usng modular multlayer structures: a VI by multple VI bottoms of the form, the underlyng VI represents the most basc functons -- calculaton, nput and output operatons. The layers of the VI structures have the same, that all levels of VI structure and nterface model s consstent, whch makes the multlayer VI can realze the nterconnecton and nested good desgn, characterstcs of whole program has the functon of the object, and modular, greatly smplfes the software structure and desgn; each VI there s a user nterface components or front panel (.e. soft panel correspond wth the actual nstrument panel), and every VI has a block dagram. The program wth a graphcal programmng language s equvalent to a tradtonal programmng language program source code. Usng graphcs nstead of the tradtonal code programmng s the bggest characterstc of LabVIEW. Three phase wthout reactve power and apparent power calculaton and sngle-phase crcut smlar. When the three-phase symmetry load, whether star or delta connecton, three-phase, and are the same, so each phase power equal to three tmes, three-phase power sngle-phase power, three-phase power, as s shown by equaton(2) [6]. P = U I cosϕ = 3U I cosϕ (2) 3 ϕ ϕ Ths part of the crcut provdes three functons, one s the value of the amplfyng or attenuatng the analog output of the converter, n order to meet the requrements of the target: the mpedance matchng, because the converter output mpedance s large and dynamc change, must be operatonal amplfer crcut s composed of a hgh nput mpedance and low output mpedance of the output buffer can wth the general target load connected; thrd s to provde low pass flter, the ladder wave output nto a smooth waveform, s a must for applcatons of arbtrary functon waveform generated by dgtal computer n ths sequence. When the samplng of multple channels, cycle samplng refers to the collecton card usng multway swtch at a clock frequency wll be more channels are access to A/D cycle samplng. Fgure 3 gves two channel crcular samplng schematc dagram. At ths tme, all the channels to share the same A/D and S/H equpment, equpped wth A/D and S/H respectvely, each channel to cheap way. Cycle samplng dsadvantage s not on the mult-channel synchronous samplng, scan rate channel s composed of multplex swtchng rate average assgned to each channel. Because multple swtch to swtch between channels, samplng of two consecutve channels, sgnal waveform wll change wth tme, the tme delay between the channels. If the channel delay between the analyses of the sgnal s not very mportant, the use of crcular samplng s possble. Fg. 3. Schematc dagram of channel cycle samplng To get data from several channels, usually use multple swtches to each sgnal termnal s connected to the converter (abbrevated). Wth the contnuous scannng method, than to each channel of an amplfer and to the economy much, but ths only apples to not very mportant occason at the tme of samplng ponts [7]. If the samplng pont of tme between strct requrements, we must also capture. For the low frequency sgnal, can be used to generate nterval scannng and samplng effects, wthout ncreasng the sample and hold crcut. Ths method n a certan tme nterval scannng nput channels, wth each channel pulse s not calculated two tmes by the scannng nterval. Sgnal Generaton LabVIEW module under the smulaton sgnal rch producton of the VI, such as sne wave 365

6 generator, Fang Bo sequence generator, trangle wave sequence generator, the unt pulse sequence generator, wave generator etc.. We wll smply take the sub VI nto a case structure to form the typcal sgnal generaton module, Swtch structure and case structure smlar to the C language, s a mult branch structure, t accordng to the nput value decson procedures nto dfferent branch flow. Calculaton of so many tmes so that DFT can not be used n practcal engneerng and t s resultng n varous DFT for reducng computaton tme algorthm. Such as 2 tme party decomposton algorthm. Those who can reduce computaton tmes, shorten the tme of calculaton, can be used for fast algorthm of DFT computng n engneerng practce s called the fast Fu Lye transform, referred to as FFT. In many software toolkt, has a varety of utlty functon or functon template avalable for use. LabVIEW provdes these functons modules. The vrtual spectrum analyzer s the man functon of the FFT transform s used to smulate the sgnal to generate, obtan the tme doman sgnal spectrum, The rotor speed N2 asynchronous motor and a synchronous speed n s the speed dfference, rato of S velocty dfference between the synchronous speed s called the "slp", as s shown by equaton(3) [8]. S = n n n 2 (% ) (3) = 2 ( )( /mn) n n s r In the L, R, C measurement system as the sgnal source, through the measured mpedance current lmtng resstor s added to the. When A s an deal amplfer and t s the measured mpedance and samplng standard resstor wth same current. The vector voltage and drect or data acquston card after sgnal condtonng to the correspondng nput channel. The man data sgnal spectrum analyzer to do the processng analyss of sgnal transformaton of Fu Lye s to get to, ts frequency dagram. So s LabVIEW n the frequency doman analyss module provdes and sgnal analyss of a large number of related functons for desgners to use, then we call the calculaton n real FFT sequence as the man data sgnal processng sub VI spectrum analyzer. Accordng to the fundamental frequency of nducton motor equvalent crcut dagram, can analyze the steady state characterstcs of the motor. Because the harmonc power supples voltage effect on the characterstcs of the motor s very small, therefore, to analyze the snusodal voltage balance. If you gnore the skn effect s ndependent of frequency, resstance, reactance s proportonal to the frequency. Rotatng magnetc flux n the ar gap n the stator wndngs Inducton EMF s E, because of the exstence of the stator leakage reactance voltage drop, so the back EMF E less than the voltage V, phase voltage effectve value can be expressed as equaton(4). E =4.44K wfnφ ur ur R uur (4) V = ( R + jx) I + ( + jx) I2 S The average value n a cycle s three-phase total nstantaneous power n a cycle of an average value. Whatever power or load s symmetrcal, regardless of load or trangular load, the above conclusons are correct. So the total power consumpton of the three-phase. The vrtual nstrument can carry out the followng 4 expermental tasks. Among them, can use the software to desgn the same task ~ 3, because they are testng the contnuous waveform. When the motor s started, the motor fnally stopped, PCI collected data contnuously conveyng to the vrtual nstrument, and then after the smple analyss, usng vrtual nstrument n the waveform dsplay. Objectve ths experment manly, qualty nspecton, operaton, shutdown startng performance of motor. Task 4, s n the stable operaton of motor. Because LabVIEW s a data flow drven programmng language, therefore n all the modules are ntegrated, more attenton should be pad to the data flow problem. Especally to the flyout panel module and t s very easy to cause the data flow confuson, error. When necessary, should use the Sequence structure to control the data flow, make t transfer data accordng to the desgner. An nducton motor maxmum torque and torque are power frequency relatonshp. Maxmum torque whch s composed of type (4) the maxmum values calculated, clearly vsble, two torques decreased serously at frequences 366

7 below 0HZ. In order to mprove the low-frequency characterstc, n the low voltage / frequency ncrease must be. Ths adjustment n the use of varable frequency power supply s not, but n the use of statc frequency converter s very easy to mplement, because statc frequency converter can ndependently adjust the output voltage and frequency. LabVIEW front panel s used to set the nput and output for observaton, the front panel to smulate real osclloscope. Because the vrtual panel drectly to consumers, s the core of the vrtual osclloscope control software. Desgn of front panel, manly consderng the beautful nterface, smple operaton, the user can smulate the tradtonal nstrument operaton through the front panel swtches and knobs, to realze the control of the vrtual osclloscope through the keyboard and mouse. The front panel s provded wth each functon module button, when you press the correspondng button, you can call the subroutne. 3. Development of Vrtual Instrument Motor Experment Teachng System based on LabVIEW The hardware platform of the vrtual nstrument conssts of a PC computer and data acquston card (DAQ card). The data acquston card s an mportant part of the vrtual osclloscope; ts performance wll drectly affect the man ndex of the samplng rate, accuracy of the vrtual. The task of data acquston system s a collecton of the orgnal sgnal, the man ndexes are samplng precson, samplng rate. Samplng precson by the converter to decde, and the samplng speed s nseparable wth samplng frequency. From the pont of mprovng the precson of angle, between the number and the samplng frequency converter s mutual restrcton. Select the data acquston card s manly related wth the samplng rate, the measurement channel, resoluton and accuracy. Data acquston s the test sgnal from the analog sgnal nto the computer to process the dgtal sgnal recevng and processng. The data acquston card s an ntegral part ts core s the A/D converter. The nput sgnal of A/D transform n tme and ampltude are contnuous analog sgnal changes, the output sgnal n tme and ampltude are dscrete dgtal sgnals, and process transformaton process from the contnuous sgnal to a dscrete sgnal can be seen as the samplng and quantzaton. Accordng to the prncple of A/D converson can be dvded nto 3 types: the method of successve approxmaton A/D, double ntegral A/D method and parallel comparson method A/D, method of convertng more applcaton n DAQ product s the method of successve approxmaton. To measure the performance of the A/D converter has two man ndexes: one s the samplng resoluton,.e. A/D converter number; two s the A/D converson rate. The test and analyss system's hardware platform s determned, for dfferent applcatons, consttute vrtual test dfferent analytcal nstrument. For the analyss of systems wth general test, and can be wdely sutable for dfferent professonal testng requrements, software usng modular desgn, system structure parameters are used n the form of varables. Therefore, the software of the data acquston module and t s data show that the type and quantty of the measured physcal quantty module, data analyss module and data processng module s shown wth the structure parameters of the specfc numercal changes. For dfferent tasks n dfferent professonal, accordng to the type and quantty of measurement ponts, only need to re set the parameters of system structure module value, matchng wll be able to complete the system hardware and software. In the cut-off frequency, frequency response decreases monotoncally. In the pass band s the deal unt response n the stopband response, zero [9]. The merts of Butterworth flter s decreasng wth smooth monotonc frequency response. The steepness of the transton zone s proportonal to the order of the flter. Butterworth low pass flter s a knd of the most flat pass band characterstcs approxmaton flters deal low-pass characterstc, as s shown by equaton(5). H(ω ) = ω + ω c 2n (5) Wdely used n automaton and control feld. The vrtual nstrument system s commonly used s the data acquston card system, together wth the control system of GPIB, VXI nstrument system as well as any combnaton between the three wth. Ths paper uses the LabVIEW software as a development platform, usng exstng equpment condtons of the laboratory to desgn a motor speed closed loop control system, wth a small amount of hardware to complete the control of motor speed, wth hgh precson and hgh effcency, easy scalablty and frendly nterface etc.. 367

8 Ths s called a cyclc Buffer mechansm. Its prncple s as follows: can put read buffer the data at the same tme put data nto the buffer, when the buffer s full, the buffer at the begnnng to store new data, as long as the data and data access speed wth the good, can be acheved wth a lmted storage area, to contnuous data transmsson. Usng a crcular buffer n the acquston of equpment, can contnuously n the background were collected at the same tme, LabVIEW s n the read buffer data two tmes the tme nterval of data processng. The fundamental frequency and frequency above two knds of crcumstances combned can be shown n Fgure 4 of the asynchronous motor varable frequency speed control characterstcs. If the motor rated currents at dfferent speeds, whch can n temperature permttng condtons are bascally long-term operaton, torque wth magnetc feld. In accordance wth the electrcal transmsson prncple, at the fundamental frequency, magnetc flux constant torque and constant, whch belongs to the "constant torque speed"; and n the fundamental frequency, the speed ncreases torque reducton, whch belongs to the "constant power speed". Fg. 4. The asynchronous motor varable frequency speed control characterstcs Some work n ths paper s desgned for software development and applcaton and LabVIEW vrtual nstrument technology, used LabVIEW to realze the system front panel, and the data processng method. The expermental system s to use PC computer dsplay (CRT) dsplay functon smulaton control panel of tradtonal nstrument, wth varous forms of expresson and output detecton result usng PC computer software can realze the functon of sgnal data calculaton, analyss, processng, acquston, sgnal condtonng and completed by the I/O nterface equpment, to complete a computer nstrument system test functon. CONCLUSION The paper proposes development of Vrtual Instrument Motor Experment Teachng System based on LabVIEW. In ths paper, the vrtual nstrument technology s appled to the motor n the laboratory constructon. Vrtual nstrument technology that use a powerful computer resources that would requre hardware to software of the technology, to acheve dfferent functons of the nstrument by callng dfferent software on the same hardware condtons, to complete a varety of parameters testng, n order to mnmze system cost, enhance system functonalty and flexblty. REFERENCES []Gong Chenglong; Zhang Mng; Zhang Le; Guo Fengyu. IJACT, 202, 4( 22), 84 ~ 847. [2]Zhenme L; Jn Shen; We Lu; YaJng Wang. IJACT, 202, 4( 23), 466 ~ 474. [3]Dong Kang-xng; Jang Mn-zheng. Journal of Chemcal and Pharmaceutcal Research,203,5(9), [4]Wang Ljun; Xng Long; Zhou Janbn. JCIT, 202,7( 22),359 ~ 367. [5]Zhhong FENG; Changyun MIAO; Hua BAI, Yanl YANG. JCIT, 203, 8(9),879 ~ 886. [6]Lu Y. JCIT, 203,8(3), ~ 8. [7]Zheng Han. Journal of Chemcal and Pharmaceutcal Research, 202,4(8), [8]Shenshen Gu; Zhjan Chen; FeWang. AISS, 20,3( 9), ~ 8. [9]Lu Lanxn; Lu Yu; ShGuangxa. Journal of Chemcal and Pharmaceutcal Research, 204,6(2),