新型地面遥控角度可调弯接头控制系统稳定性研究

为了提高井下底部钻具组合的适应性和调控能力，研制出了一种新型的地面遥控角度可调弯接头。运用稳定性理论和传递函数法，重点分析了新型可调弯接头控制系统的稳定性。采用定步长四阶龙格一库塔方法对其动态响应进行了数字仿真，讨论了各主要参数对控制系统瞬态响应的影响以及系统正常工作的范围。结果表明，为保证本文所分析的可调弯接头在井下正常工作，钻并时钻并液排量波动量应为２．２Ｌ／ｓ

STABILITY ANALYSIS OF CONTROL SYSTEM FOR A NEW REMOTECONTROLLED ADJUSTABLE BENT SUB

A new my of remote-controlled adjustable bent sub is developed to improve the flexibility and controllability of a bottomhole assembly. Theory of stability and the transfer function method are used to analyze the stability of a control system of the bent sub. Numerical simulation for the dynamic response is carried out by algorithm of Runge-kutta method with fixed step length and four orders. The stability and normal operating conditions of the control system are analyzed in detail. The results indicate that the flow fluctuation of drilling fluid must be about 2. 2 L/s in order to make the adjustable bent sub work reliably in downhole.