基于LQR控制的混合轴承动态特性分析

Analysis of the Dynamic Characteristics of Active Hybrid Bearings Based on LQR Optimal Controller

针对主动混合滑动轴承,给出了基于线性二次最优调节器(LQR)的控制策略,分析了轴承的动态特性。采用扰动压力法求解轴承的8个动力特性系数和灵敏系数;给出了不同权重矩阵下轴承动态特性系数的计算结果,并进行了分析讨论。结果表明,LQR控制简单易行,灵活性强,可以有效改善轴承系统的动态特性,降低交叉刚度,提高直接刚度和阻尼,从而改善系统的稳定性。

The dynamic characteristics of active hybrid sliding beatings based on a Linear Quadratic Regulator （LQR） optimal controller were analyzed. The dynamic coefficients and the sensitivity coefficients were computed by using perturbation method. Computation results for different weighting matrix were given and discussed. It is shown that the proposed LQR optimal controller is easy to implement and works well in enhancing the dynamic characteristics of the active bearing,i. e. reducing the cross stiffness and increasing the direct stiffness and damping coefficients. The stability of the bearing system is improved.