Research On Down-hole Signal Sampling And Transmission Method

ESP (Electrical submersible pump) is one important machine oil extraction equipment in oil exploiting, which providing the advantages of the great vent mete, high raise order, convenience management and easy operation, it can be used in slant well, level well and oil extraction on sea and gains broad appliance in oil filed, its reliability and high validity are very import for the continuance and steady high yield in oil field. The research on state monitoring of ESP has important significance and practical value for highly efficient and reliable ESP.Submersible pump to maintain efficient production, and stable production rate and improve Collection efficiency, At present, many submersible pump unit driven by inverter, In this paper, a multi-parameter condition monitoring technology of the ESP driven by inverter is researched. There are seven parameters needed to be detected and transmitted: the inlet pressure, the outlet pressure, the environment temperature, the electrical machinery's temperature, the vibration of X direction, the vibration of Y direction.Submersible pump condition monitoring system measuring many parameters, there is lager distance between down-hole devices and ground equipment, and there is a converter of harmonic interference, therefore, transmitting the down-hole signal to groun is one of the main problems of the subject. Power line carrier is used to transmit signal, the corresponding coupling circuit is developed, and made down-hole state monitor's signal coupled to the submersible cable, which is transmitted to ground in the form of power line carrier transmission. Power supply and signal transmission of underground equipment are through the submersible cable.In order to reduce power consumption of down-hole devices and to ensure the accuracy and reliability, the underground circuit is designed based on system-level single-chip MSC1211 which is the core processor to measure the ESP's seven running parameters. The subject also developed the signal processing module based on TMS320LF2407 to deal with and demodulate the signals from the receiving device on the ground, and design the master device of the system on ground based on AVRmega128 to achieve data show, human-computer interaction and early warning and other functions. Dual SD card data storage program was designed, a communications program which is suitable for transmitting many parameters between several processor is presented, which improve data transmission reliability and efficiency.