关键词: 液压伺服系统；故障诊断；非线性观测器；残差

Abstract:

Decreased pressure fault of hydraulic servo system was diagnosed based on nonlinear observer. The nonlinear observer model was presented and the outputs were simulated. Residual error, which was generated by comparing model outputs with system outputs, was evaluated based on thresholds using interval models. The performance of the proposed fault diagnosis scheme was demonstrated in detecting decreased pressure.

Key words: hydraulic servo system；fault diagnosis；nonlinear observer；residual error