Research on transmission of technology of downward information security for wellbore trajectory control

Information transmission is an important part of the wellbore trajectory automatic control system. Combined with the characteristics of the guided drilling system, drilling fluid pulse is selected as a tool for trajectory control. Negative pulse transmission of drilling fluid is one of the key technologies to realize wellbore trajectory automatic control. In this paper, the working principle of negative pulse propagation of drilling fluid is introduced. The characteristics of negative pulse propagation and signal pretreatment of drilling fluid are analyzed emphatically. Signal correlation analysis method is proposed for signal transmission of drilling fluid negative impulse well. In this paper, the propagation characteristics of drilling fluid pressure pulsed downward transmission system are studied deeply. The influence of various drilling parameters on the drilling fluid pressure pulse is analyzed, and the model of drilling fluid pressure pulse is presented. Experimental results show that the proposed method can effectively separate useful signals from interfering signals. It is verified by field experiment that the success rate of information decode system designed by this method is high, which can meet the requirement of well trajectory precise control.