电液比例式推进系统的自适应反演滑模控制

Adaptive backstepping sliding mode control for electro-hydraulic proportional propulsion system

针对电液比例阀驱动的水下推进系统存在液压系统强非线性、易受外界温度压力以及水动力性能变化引起的参数不确定性的问题,提出一种自适应反演滑模控制方法.该方法结合实验辨识和自适应参数控制器设计方法分别对电液比例复杂耦合系统和不确定系统参数进行简化分析和在线估计,使用李雅普诺夫稳定性理论保证了系统全局渐近稳定以及系统状态的有界性.以国家发展高科技计划4 500米级深海作业系统-"海马号"ROV的螺旋桨推进系统为研究对象,使用提出的控制方法与传统PID控制器进行对比试验.仿真和水池试验结果表明,所设计的自适应反演滑模控制器对参数变化以及未知外界干扰具有较强的鲁棒性,可以很好地跟踪螺旋桨转速参考轨迹,获得较好的稳态控制精度和动态性能;同时修正后的参数估计能够保证在外界未知干扰下估计参数的有界性.

A adaptive backstepping sliding mode control method was proposed based on the fact that underwater hydraulic propulsion system controlled by electro-hydraulic proportional valves has the control characteristics of strong nonlinearity of the hydraulic system,unknown hydrodynamic parameter,parametric uncertainties susceptible to temperature and pressure changes of the external environment.The controller combined with experimental identification method and the robust adaptive controller design method to analyse complex electro-hydraulic system and estimate unknown parameters.The globally asymptotic stability and boundedness of the controll system was guaranteed by using Lyapunov stability theory.Using the hydraulic propulsion system for the 4 500 m Deep-sea Working System as the research subject,a comparative study was conducted using the control method presented in this paper and PID controller.Both the simulation results and the test results indicate that the proposed controller with strong robustness can track the desired reference trajectory of thruster speed with satisfied dynamic performance and steady accuracy.The modified parameter adaptive laws can also guarantee the boundedness of the estimated parameters.