Abstract
Background: The optimal control strategy has been widely used in electro-hydraulic
position servo systems to achieve high-precision position tracking. However, the difficulty of selecting
the weighted matrices in optimal control often leads to poor tracking accuracy.
Objective: This patent proposes an optimal control strategy using a genetic algorithm to improve
the tracking accuracy of the electro-hydraulic servo system.
Methods: The patent first established the system state equation of the valve-controlled asymmetric
cylinder. Secondly, based on linear quadratic optimal control theory and genetic algorithm, an
optimal control strategy using a genetic algorithm was proposed. Finally, the simulation and experimental
results showed that the designed controller has high position tracking accuracy.
Results: The optimal controller using a genetic algorithm was designed using Matlab/Simulink,
and the effectiveness of the controller was verified through simulation. Additionally, experimental
results showed that the proposed optimal control controller using a genetic algorithm had higher
tracking accuracy than the proportional-integral-derivative controller and traditional backstepping
controller for a given reference signal.
Conclusion: The control technology of the optimal controller using a genetic algorithm was found to
be superior to proportional-integral-derivative and traditional backstepping controllers, and the tracking
error of the linear quadratic regulator controller was reported to be relatively small. This demonstrated
the effectiveness of the optimal control strategy using a genetic algorithm in this patent.
Keywords:
Hydraulic actuator, linear quadratic regulator, genetic algorithm, position tracking, optimal controller, genetic algorithm.
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