基于子空间辨识的阀控液压缸泄漏诊断方法

为提高阀控液压缸泄漏检测的准确性和效率,提出一种基于子空间辨识的液压缸泄漏诊断方法。选取液压缸活塞杆外力负载作为输入信号,两腔压力、活塞杆位移与速度作为状态变量,建立系统状态空间模型;应用子空间辨识运算得到系统矩阵相关元素的估计值,并由此判断泄漏故障的存在、类型与严重程度。基于MATLAB-Simulink仿真模型对该诊断方法进行了数值仿真验证,结果表明该方法有效且具有较高的准确性。

Diagnosis Method Based on Subspace Identification for Valve-controlled Hydraulic Cylinder Leakage

We propose a fault diagnosis method based on subspace identification for leakage fault detection of valve-controlled hydraulic cylinders. Firstly，a state-space model for the system is established, in which an external force load of piston of hydraulic cylinder is selected as the input signal, and the pressure of the two chambers, displacement and velocity of piston rod are chosen as the state variables. Then, the estimation value of specific elements of the system matrix can be obtained in terms of subspace identification theory. On this basis, the existence, type and severity of the leakage fault are determined. Finally, a numerical simulation is conducted by MATLAB-Simulink to verify the proposed method. The results demonstrate that the proposed method is effective and has high accuracy.