【作者】 张健；

【导师】 沈跃；

【作者基本信息】 中国石油大学(华东) ， 物理学， 2017， 硕士

【摘要】 现代钻井技术中,井下与地面间的实时信息互传一直是研究的热点。无线随钻测量系统(MWD)是钻井工程中普遍采用的一种现代钻井辅助系统,其信号传输的核心部件是钻井液连续压力波信号发生器;其中旋转阀转速的快速随动控制决定了信息调制的效果,并对压力信号的传输产生重大的影响。因此,转速控制的研究可以为MWD系统的研制提供理论指导和技术支持。基于旋转阀的结构设计与转子受力分析进行了旋转阀负载力矩的数学建模及特性分析,基于旋转阀轴向力的数学模型进行了旋转阀负载力矩的多项式拟合,以此为依据建立了电机驱动下旋转阀的转角与转速方程。通过非线性补偿的方法消除控制项的非线性特征,实现了转速方程的线性化,建立了旋转阀转速的开环控制模型并分析了干扰项对旋转阀转速输出的影响机理。引入前向PID控制建立了复频域下转速PID闭环控制模型,建立了干扰项转速的跟踪延迟时间、流量测量误差以及负载力矩的数学模型偏差对转速输出影响的数学模型,通过PID参数的合理选择,使用留数法分析计算和Simulink仿真方法对干扰项影响下的旋转阀转速进行了理论计算与仿真分析。理论研究与仿真分析表明,采用基于前馈补偿的旋转阀转速控制系统线性化校正方法配合优化的PID参数取值,可以实现旋转阀转速的快速随动控制及较高的抑制干扰能力,为旋转阀的转速控制提供了理论分析基础。更多还原

【Abstract】 The research on the information transmission from the underground to the ground is a hotspot in the field of modern drilling engineering.Measure while drilling(MWD)is a kind of modern drilling engineering supporting technology,of which drilling fluid pressure wave generator is the core device.The fast follow-up control of the rotating speed of the rotary valve determines the effect of the signal modulation,and has a significant influence on the transmission of the pressure signal.Therefore,the research of speed control of rotary valve can provide theoretical guidance and technical support for the development of MWD system.According to the structural design and rotor force analysis of rotary valve,the mathematical model and characteristic analysis of the load torque of the rotary valve are carried out.Based on the mathematical model of the axial force of the rotary valve,polynomial fitting of the load torque of the rotary valve was built,and rotation angle and speed equation under motor drive of rotary valve was established on this basis.By nonlinear compensation,elimination of nonlinear characteristics of control,the linearization of the rotational speed equation is realized,and the open loop control model of rotary valve is established.According to this,the influence mechanism of the disturbance on the rotational speed of the rotary valve is analyzed.Besides,the forward PID control is used to establish the PID closed loop control model in complex frequency domain,the mathematical model of the influence of the deviation of the rotation speed,the measurement error and the load torque on the rotational speed output is established.With the reasonable selection of PID parameters,using residue method and Simulink simulation,the theoretical calculation and simulation analysis of the rotating speed of the rotating valve under the influence of disturbance has been done.Theoretical research and simulation analysis show,with the optimization of PID parameters,linearization correction method of rotary valve speed control system based on feedforward compensation,fast follow-up control of rotary valve speed and high interference rejection ability can be done.It provides a theoretical basis for speed control of rotary valve.更多还原