Robust Control of the Nonlinear Hydraulic Servo System Using a PID Control Technique

PID 제어 기술을 이용한 비선형 유압 시스템의 강인 제어

  • Yu, Sam-Hyeon (Dept.of Ordnance Engineering, Korea Military Academy) ;
  • Lee, Jong-Won (Dept.of Mechanical Engineering, Chungang University)
  • 유삼현 (육군사관학교 무기공학과) ;
  • 이종원 (중앙대학교 기계공학과)
  • Published : 2001.05.01


Even though the hydraulic servo system has been widely used in industrial and military equipments since it has a lot of advantages, it is not easy to design controller due to the high nonlinearities and the parametric uncertainties. The dynamic behavior of the real process in the hydraulic servo system differs from that described by its model because the model is linearized. Another reason of the difference is caused by the variety of parameters, since the system parameters of the dynamic equation are affected by the operating conditions such as temperature and pressure. In this study, the designing process of the MRNC with a PID compensator is introduced and applied to the load sensing hydraulic servo system. The results show that the designed controller guarantees the robust control performance despite of both the nonlinearities and the parametric uncertainties.


Model Reference Nonlinear Controller;MRNC;Relative Degree;Error Dynamics;Parametric Uncertainty;Lie Derivative;Bulk Modulus;Load Sensing Hydraulic System


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