Development Of Data Acquisition And Processing System Of Frequency Control Cabinet Applied To Pumping Unit

In order to improve the intellectualized control degree of frequencyconversioncontrol cabinetappliedtobeampumpingunit,andoptimizespeedratio of up-stroke and down-stroke, it demands a real-time sampling of theelectrical parameters of the frequency conversion control cabinet. Therefore,the data acquisition and processing circuit of the master-slave distributedcontrol system with PC and AT89C51 single chip computer is designed. Thesystem is used to sample and process the electrical parameters of thefrequency conversion control cabinet, such as current, voltage, frequency,powerfactorandsoon.Firstly,this paper analyzed the composition and developing trend of dataacquisition and processing system, and the current applied status offrequency conversion technology in the oil field, and introduced themeasuring principle of the electrical parameters of the frequency conversioncontrol cabinet. Secondly, this paper designed the hardware circuit andsoftware. The hardware circuit centered on AT89C51 is made of signalconditioning circuit, wave shaping circuit, A/D conversion interface circuit,memory interface circuit and serial communication interface circuit. The software consists of the upper and lower computer software. The subordinatecomputer software with assembly language implements data acquisition andtransmission function; the superordinate computer software with Visual Basicimplements data receiving, processing, and saving function. Lastly, theanalogous and field test results show the data acquisition and processingsystem is feasible and can fulfill the demands of measurement.