大型装备电液系统鲁棒H_∞位置控制

针对大型装备电液系统非线性、参数不确定性问题,建立了比例阀控非对称缸液压系统的非线性动态模型。考虑反馈控制,建立了具有不确定参数系统线性化数学模型。基于边界理论和线性矩阵不等式,提出了电液系统鲁棒H_∞位置控制策略。着重考虑系统结构化系数的擅动,构建了具有积分行为的H_∞控制器,设计了估测系统内部状态的观测器。通过仿真和实验,验证了提出的算法和控制策略。对比了系统参数不变、外负载力变化下和系统参数变化下系统的鲁棒性和稳定性。仿真和实验结果表明,提出的具有积分行为的鲁棒H_∞位置控制策略能提高系统的鲁棒性和稳定性。

Robust H∞ position control of electro-hydraulic system in large equipment

For the problems of nonlinearity and uncertain parameters of electro-hydraulic system for large equipment, a nonlinear dynamic model of the proportional valve control asymmetric cylinder hydraulic system was developed. For the purpose of feedback control, a linearized mathematical model of the system with uncertain parameters was derived.Based on boundary theory and linear matrix inequalities, a robust H∞ position control strategy of electro-hydraulic system was put forward. Furthermore, the perturbations of structure coefficients in the electro-hydraulic system were focused on consideration, a H∞ controller with the integral action was proposed, and an observer estimating internal states of the system was designed. Finally, the proposed algorithm and control strategy were verified by simulation and experiment. The robustness and stability of system were compared under the conditions of the external load changes and the system parameters changes. The simulation and experiment results show that the given robust H∞ position control strategy with the integral action can enhance the robustness and stability of system.