基于升沉预测的钻柱补偿装置仿真研究

为减小大洋钻探过程中井底钻压波动,提高钻柱补偿装置的补偿精度,开展了基于非水动力学船舶升沉预测方法的仿真研究。首先以船舶姿态传感器的升沉位移信号为输入,建立基于卡尔曼滤波的升沉预测模型,然后利用AMESim平台搭建450T死绳端钻柱补偿装置仿真模型,通过仿真的形式实现波浪信号的采集、处理和预测,再对引入升沉预测前、后的补偿性能进行对比分析,并针对升沉预测时间和海况对补偿性能的影响展开深入探讨。仿真结果表明:采用卡尔曼滤波进行升沉预测的方法计算量小、实时性高,能有效进行短期的升沉预测;升沉预测的引入可减小井底钻压波动、提高补偿性能,理想情况下,预测时间在0.4 s左右时补偿性能最优,而对于补偿精度要求高的场合,应在较好的海况作业且开启升沉预测为宜。研究结果可为钻柱补偿装置设计和控制系统优化提供一定的指导。

Simulation on Drill String Compensation Device Based on Heave Prediction

In order to reduce the weight on bit(WOB)fluctuation and improve the compensation accuracy of the drill string compensation device during the ocean drilling process,the research is carried out based on the non-hydrodynamic ship heave prediction method.Taking the heave displacement signal of the ship attitude sensor as input,a heave prediction model based on Kalman filter is established.The AMESim platform is used to build a 450T dead line end drill string compensation device simulation model.The collection,process and forecast of wave signals are carried out through simulation.Then,the compensation performance before and after the introduction of heave prediction is compared.In-depth discussions on the influence of heave prediction time and sea states on the compensation performance are carried out.The simulation results show that the method of using Kalman filter for heave prediction has a small amount of calculation and high real-time performance,which can effectively carry out short-term heave prediction.The introduction of heave prediction can reduce bottom hole WOB fluctuation and improve compensation performance.Ideally,the compensation performance is optimal when the prediction time is about 0.4 s.For occasions that require high compensation accuracy,it is appropriate to operate in better sea states and carry out heave prediction.The research can provide certain guidance for the design of the drill string compensation device and the optimization of the control system.