双频多电机自同步振动系统的同步机理与同步控制策略研究

In the technology of fast drilling for shale horizontal wells, drilling shakers are critical devices for cleansing and recycling drilling fluid. For the problem that self-synchronous drilling shakers are unfitted for the requirements of the fast drilling in shale horizontal wells, the theoretical and experimental means for the screening of drilling fluid by using a self-synchronous vibratory system with dual-frequency and multi-motor excitation are proposed. But it is not clear about synchronization mechanism, screening characteristics and synchronization control of the system, which causes the lack of theoretical basis for studying of source and control for the synchronization phenomenon. Hence, this project explores the synchronization mechanism, screening characteristics and synchronization control strategy around the self-synchronous vibratory system with dual-frequency and multi-motor excitation. Firstly, the vibrating mechanics and the stability theory of nonlinear system are employed to ascertain the synchronization mechanism and dynamic characteristics, which is induced by the vibration of electromechanical coupling in the system. Subsequently, a two-way coupling method based on CFD (Computational Fluid Dynamics) and DEM (Discrete Element Method) is adopted to reveal the screening characteristics and the mass fluctuation of the drilling fluid. Finally, a synchronization control strategy with cross coupling is applied to solve the synchronous instability, which is induced by the mass fluctuation of the drilling fluid on screens. This work will promote the technology development of fast drilling for shale horizontal wells and settlement of the common scientific issues in vibrating synchronization.

在页岩水平井快速钻井技术中，钻井振动筛是净化和循环钻井泥浆的关键设备。针对单频自同步振动筛不适应页岩水平井快速钻井作业的问题，提出双频多电机自同步振动系统实现钻井泥浆筛分的理论和实验研究方法。现有研究对双频多电机自同步振动系统的同步机理、筛分特性和同步控制尚未明确，因而对系统的同步溯源及控制缺少充分的理论依据。本项目围绕双频多电机振动自同步振动系统的同步机理、筛分特性和同步控制策略展开研究。首先，采用振动力学和非线性系统稳定性理论，研究双频多电机自同步振动系统由机电耦合振动诱导的同步机理和动力特性。其次，采用离散元法与计算流体动力学双向耦合法，揭示双频多电机自同步振动系统的筛分特性和泥浆质量波动的规律。最后，采用交叉耦合同步控制策略，解决钻井泥浆质量波动诱发系统自同步状态失稳的问题。研究成果对页岩水平井快速钻井技术的发展和振动同步领域共性问题的解决具有促进作用。

在页岩水平井快速钻井技术中，钻井振动筛是净化和循环钻井泥浆的关键设备。针对单频自同步振动筛不适应页岩水平井快速钻井作业的问题，提出双频多电机自同步振动系统实现钻井泥浆筛分的理论和实验研究方法。现有研究对双频多电机自同步振动系统的同步机理、筛分特性和同步控制尚未明确，因而对系统的同步溯源及控制缺少充分的理论依据。本项目围绕双频多电机振动自同步振动系统的同步机理、筛分特性和同步控制策略展开研究。首先，采用振动力学和非线性系统稳定性理论，研究了双频多电机自同步振动系统由机电耦合振动诱导的同步机理和动力特性；发现电机转差率致使双频多电机振动系统很难实现倍频自同步运动，低频电机安装位置显著影响双频多电机振动系统同步状态。其次，采用离散元法与计算流体动力学双向耦合法，揭示双频多电机自同步振动系统的筛分特性和泥浆质量波动的规律；发现当物料与振动体质量比小于10%时，振动系统具有稳定的周期运动；当质量比大于等于14%时，振动系统进入混沌运动状态；当采用24.5-49Hz组合频率时，双频激励振动系统的泥浆处理效率最佳。最后，采用交叉耦合滑模控制策略，解决了钻井泥浆质量波动诱发系统自同步状态失稳的问题；比较双频多电机振动系统的自同步与控制同步，发现受控对象的动力学特性不受系统参数变化的影响和外界载荷的干扰，具有较强的鲁棒性。研究成果对页岩水平井快速钻井技术的发展和振动同步领域共性问题的解决具有促进作用。