Research On Load-adaptive Control Of The Drilling System Of Rotary Drilling Rig

Rotary drilling rig is a high-tech product in engineering machinery field, which has been widely used in filling pile, concrete diaphragm wall, foundation reinforcement and a variety of ground foundation construction. In this paper, considering the drilling system of a certain type of rotary drilling rig as the research object, conduct the theoretical analysis, simulation and experimental research of self-adaptation to load at the working process.Firstly, analyzed the working conditions of rotary drilling rig when drilling, introduced each hydraulic system loop associated with the drilling work in detail, explored the control mode of the major components in the system, which provides the theoretical basis for the determination of the whole control system.Secondly, according to the adaptive control requirement of the drilling-work system in rotary drilling rig, the control scheme of operating mode is proposed, which is based on constant power control; Using the feedback fuzzy PID control for engine rotation-speed and load-limit control of A8 VO variable pump, realized the matching between the output power of the engine and the absorbed power of variable pump; Combined simulation model of the power head system was established by means of AMESim and Simulink. based on this model the simulation of the drilling process was conducted, which verified the control strategy is feasible in theory, and provided reference for the debugging and improvement of the system.Thirdly, according to the control object of drilling system, the electronic control scheme, which is based on CAN bus, was determined; the function of the control system was planned, based on which the hardware selection and software function design of the control system was conducted, then completed the design of the control system.In the end, applied the designed electronic control system to a certain type of rotary drilling rig, and treated it as the experimental platform, then conducted experiment for the drilling process. through the analysis of the collected data, the feasibility of the control strategy in actual work is verified.