Fixed Time Fault-Tolerant Control of Electro-hydraulic Servo System based on RFESO

Xing Ren

Abstract: A fixed time fault-tolerant control method is proposed for electro-hydraulic servo systems, which can ensure high-precision displacement tracking control of hydraulic cylinders within a fixed time in the presence of unknown nonlinearity, external disturbances, and actuator faults in the system, and the convergence time and performance are independent of the initial state of the system. This article first designs a reduced order fixed time extended state observer RFESO for estimating the lumped uncertainty of electro-hydraulic servo systems. The observer only requires two orders, effectively reducing computational complexity, and the estimation error can achieve fixed time convergence. Secondly, based on the designed RFESO, this paper develops a fixed time fault-tolerant controller for the electro-hydraulic servo system, which does not require any information about the overall uncertainty of the system. Finally, the effectiveness of the proposed method was simulated and verified in the Matlab/Simulink environment, and relevant experimental verifications were conducted on the electro-hydraulic servo system experimental platform.

Submission Number: 196