Research On Control Strategy And Experiment Of Engine System Power Matching On Rotary Drilling Rig

ABSTRACT:As one of the complicated and large inertia engineering equipments, rotary drilling rig is widely used in the bored piles hole-forming operation. The efficiency and stability of operation has always been strongly concerned about. On one hand, due to the existing rotary drilling rig power reserve up to29%, resulting in low utilization of engine power. One the other hand, with the complicated operation condition and a wide range of load variations, engine speed volatile in working condition. In response to these problems, one engine power matching scheme for rotary drilling rig was put forward from the perspective of theory, simulation and test research.The development of construction machinery power matching technologies both in China and abroad of rotary drilling rig was overviewed. Based on the analysis of the features of the working condition of rotary drilling rig and the current system of other construction machine, a method suitable for the rotary drilling rig’s is proposed in order to improve the efficiency and stability of rotary drilling rig construction.The engine fuel consumption model and dynamic model was established through analyzing the working characteristics of engine. At the same time, based on the analysis of electronic control principle, the variable displacement pump mathematical models was constructed. Combined with the engine variable pump power system simulink simulation model, a simulation and research platform was provided. Considering the characteristics of nonlinear and the changing construction parameters, the control strategy which is based on rotational speed sensing about load-limiting control, and single neuron PID control algorithms was used. Additionally, power matching simulation analysis was conducted so as to provide the reference and theoretical basis.A series of experiments were conducted. Firstly, the rotary drilling rig wireless testing system was set up in order to provide the basic testing tools. Secondly, the variable pump control current-torque relationships was measured to establish mathematical model. Thirdly, the stable working parameters of the engine were obtained under different rotational speed and load in order to build the mathematical model of speed adjustment the engine characteristics. Fourthly, with overflow load experiments, the effectiveness of load matching method was verified. Last, the effect of the power matching optimization was quantified by making comparative test.