Development Of Accompanying Vibration Cementing Rubber Plug Control System

Cementing is an important operation process in petroleum engineering.Traditional vibration cementing technology,because the vibration source is installed at the wellhead or the bottom of the well,the vibration wave is continuously attenuated under the effect of damping,which is not ideal for wells with a depth of several kilometers.Dynamic vibration cementing technology,on the basis of giving full play to the role of traditional vibration cementing,with the continuous downward movement of the exciter in the casing string,the resonance response of the entire well section can be achieved,greatly improving the cementing quality.This paper uses the finite element analysis software to get the best excitation frequency,takes the brushless DC motor as the executive component,and uses the fuzzy PID algorithm to control,and design the hardware circuit and software program of the control system,try out the physical prototype to complete the host computer debugging.Establish the Euler-Bernoulli beam mechanical model of the casing string,and use the Newtonian mechanical formula to derive the calculation formula of the lateral natural frequency of the casing string;establish the fluid-solid coupling of the casing string-drilling fluid-cement slurry in the finite element analysis software Ansys Workbench Model,the natural frequency and modal vibration mode are obtained through modal analysis,and the excitation frequency that maximizes the vibration displacement amplitude of the casing column structure is obtained through harmonic response analysis,which provides a basis for the design of the exciter control system;the control system uses brushless The DC motor is used as an actuator to analyze the mathematical model and motion equation of the brushless DC motor.The fuzzy PID algorithm is used to control the closed-loop speed.The control system block diagram is built by the Matlab Simulink module,and the fuzzy PID control algorithm is compared with the traditional PID algorithm.Make the response speed of the control system faster and more robust;design the overall scheme of the hardware of the control system,and complete the circuit construction of each module;On the basis of the circuit construction,Keil lower computer programming software is used for programming;finally the prototype trial production is completed,and the written upper computer is used for system debugging.The control system has passed the acceptance of an oil field,which is of great significance for improving cementing quality and cementing efficiency.