Technology of magnetic induction transmission of intelligent drill pipe and its channel characteristics

Key words:  intelligent drill pipe  inductive coupler  magnetic induction transmission  high frequency transformer model  circuit model  capacitance compensation

Abstract:

Based on a high frequency transformer model, an accurate circuit model of inductive coupler was established by combining theoretical analysis on the magnetic inductive coupling principle and coupler simulations. The analysis results of the characteristics of multiple couplers connection show that adding a coupler would result in increase of a resonant circuit, therefore a circuit model of the magnetic inductive transmission channel was obtained. To solve the problem of attenuation in the multisection signal transmission, capacitance compensation was adopted to increase the amplitude of the resonant frequency, thus to improve the efficiency of the signal transmission. To verify the circuit model of the magnetic induction channel, an experiment of the data transmission with drilling was carried out. By selecting two resonance frequencies in the model as communication frequency, a 115.2kbit/s communication rate in section 20of the transmission system is achieved.