海底钻井液举升钻井系统监测与控制

海底钻井液举升钻井(SMD)技术可以有效地解决常规深水钻井压力梯度区间较窄的问题,复杂的海洋钻井环境为其实现造成了一系列的控制难题。结合SMD系统的组成和基本功能,选择PXI系统作为海底钻井液举升钻井监、控系统的硬件平台,基于Labview开发SMD系统监控程序。结合SMD的作业流程和工况特点,根据模糊控制理论,设计实现SMD系统模糊控制器,解决SMD系统大惯性、大时滞的控制难题。通过海底钻井液举升钻井试验平台对所开发的监控系统性能进行验证。试验结果表明:监测模块可精确测量SMD系统的各项运行参数;模糊控制器能够快速有效地保证泵的入口压力维持在某一恒定值附近,系统能可靠地应对井涌、井漏等异常工况的发生。

Monitoring and control for subsea mudlift drilling system

Subsea mudlift drilling (SMD) technique may be applied effectively in deep water drilling operation where the difference between the formation pore pressure and fracture pressure is small.A monitoring and control method for SMD was presented. The method is effective in both suppressing interferences which come from various factors in the complex deep water environment, and in proving the robustness of system. Taking into consideration the components and basic functions of SMD systems, PXI module is selected as the hardware platform for monitoring and control sub-system of SMD systems, in which the monitoring and control program is developed based on Labview. By applying fuzzy control method, a new fuzzy controller is designed as the operation procedure to overcome the large inertia and delay time problems in SMD systems. The performance of monitoring and control system is tested and verified in experimental platforms for SMD. Experiment results show that the parameters of the operation processes for SMD systems may be precisely measured by the monitoring module, and the pump inlet pressure can be maintained at nearly a constant level, a crutial property of fast responding systems to critical conditions such as well kick and circulation loss.