Research On On-line Condition Monitoring And Transmission System For Electrical Submersible Pump In Downhole

With the development of the oil production in the middle and late stage, electric submersible pump(ESP) production method has become one of the most vitality methods for artificial lift. The downhole tool is an important corollary equipment of the ESP, which supplies the power by means of the ESP cable. By using the analog current loop technique, it can detect the downhole work condition and transmit the corresponding parameters.In this thesis, the on-line condition monitoring and transmission system for Electrical Submersible Pump is mainly used to measure temperature and pressure. The temperature reflects motor temperature. The pressure is the submergence. The whole system can be divided into two parts, the ground system part and the underground system part. The ground system provides the DC voltage signal for the underground system by the star potentiometric method. In order to realize the on-line monitoring the work condition of the downhole ESP, the real-time current signal shall be processed, displayed and transmitted. The signal of the sensor is simply processed by the downhole monitoring system,and the underground system converts the data of pressure sensor and temperature sensor to current signal, which is transferred to the ground. Motor side of harmful voltage is analyzed and inhibited. It is used to guarantee the work of the downhole circuit reliable and normal. Moreover, the paper also puts forward ideas of the design of multi-parameter to increase the measurement range.Theoretical analysis results and the experimental data have proved that this system has many advantages, including a simple power supplement, efficient signal transmission, reliable data processing, the remote monitoring, etc. This system can offer reliable technical support to optimize the ESP production. It provides a strong support for the development of ESP production in the direction of stripper wells and land wells. It also enhances the ability of developing the intelligent wellbore in our country.