Study On Screw Operating Parameter Monitoring System

Screw pump is widely used in the petroleum industry as an oil lifting device. The diagnostic techniques for screw pump operating condition monitoring are outdated in present years, and the estimate for operating condition is mostly depending on direct experience of site engineer. These experiential data is often related with stress condition of turning bar, working voltage and current of the driving motor, which can be acquired by measuring in work site, but can hardly extract the changing law of screw pump from these data. The stress of turning bar is a very important parameter for recognizing pump operating condition. It has been difficult for many years to obtain the stress data for lagging in stress sensor technique. By developing of electrical measuring technique and wireless data transmission method, it has become a new research zone that can gain the model when the screw pump is working by monitoring the changes of driving motor’s electrical parameter. Although, it has advantages on real-time monitoring and diagnosis, all the data obtained by electrical measuring must gave manual analysis in order to gain the operating condition of the pump. Comparing with automatic analysis, the manual method may lead to delay for faulty recognition, which can make great lost when pump has some bad damage.This research focuses on electrical parameter analysis for screw pump faulty diagnosis. Designed a diagnostic method based on embedded microprocessors, three-phase power metering chip as the core part of the on-site monitoring, to realize the screw Real-time monitoring and collection of three-phase motor drive voltage, current, frequency, active power, reactive power, power factor and other parameters, and the data stored in the memory; the system can automatically screw motor reactive power compensation, and able to break the rod, pump card, lack of power equal catastrophic failure judgment, promptly shut off, and an alarm signal.Designed screw pump operating condition monitoring system using Texas Instruments digital signal processor(TMS320F2812) as computing core. The drive motor’s electrical parameters are acquired by electric energy measuring chip(ATT7022B) which make the data transmission to DSP that do data processing job in this system. File system firmware chip(CH376S) collects data into USB flash disk. All the data can be transport though WLAN to data management centre.