基于自抗扰方法的深海自持式智能浮标的定深控制研究

摘要：

深海自持式智能浮标在下潜过程中, 随着深度增加将会引起浮标壳体形变, 使得浮标的自身净浮力产生变化, 而浮标净浮力的变化将会影响浮标的定深性能。 为了使浮标在实际定深工作中更好地抵抗净浮力和水阻力所构成的外部干扰, 提出了基于自抗扰控制技术的定深控制器设计方法以提高深度定位效果。 首先, 通过分析浮标的运动过程, 建立了动力学模型。 然后, 基于李雅普诺夫稳定性原理来设计扩张状态观测器和非线性状态误差反馈控制器。 最后， 将所设计的自抗扰深度控制器与基于传统的PID方法的定深控制器进行了半实物仿真实验对比。 仿真实验结果表明, 基于自抗扰控制技术的深海智能浮标深度控制方法能够实现准确的定深跟踪控制, 相比于传统PID控制器, 自抗扰深度控制器的超调量为1.74%, 深度误差在0.5%以内。 自抗扰深度控制方法能够更有效地抑制净浮力和水阻力共同干扰下所造成的超调和震颤等现象， 提高了深海自持式智能浮标进行深度跟踪任务时的智能性。

The net buoyancy of the deep-sea self-holding intelligent buoy (DSIB) will change with depth due to pressure hull deformation in the deep submergence process. The net buoyancy changes will affect the hovering performance of the DSIB. To make the DSIB have better resistance to the external disturbances caused by the net buoyancy and water resistance, a depth controller was designed to improve the depth positioning based on the active disturbance rejection control (ADRC). Firstly, a dynamic model was established based on the motion analysis of the DSIB. In addition, the extended state observer (ESO) and nonlinear state error feedback controller were designed based on the Lyapunov stability principle. Finally, semi-physical simulations for the depth control process were made by using the ADRC depth controller and traditional PID depth controller, respectively. The results of the semi-physical simulations indicate that the depth controller based on the ADRC can achieve the predefined depth control under the external disturbances. Compared with the traditional PID depth controller, the overshoot of the ADRC depth controller is 1.74%, and the depth error is within 0.5%. It not only has a better control capability to restrain the overshoot and shock caused by the external disturbances, but also can improve intelligence of the DSIB under the depth tracking task.