|
Wei Jianhua
Guan Cheng
State Key Laboratory of Fluid Power
Transmission and Control,
Zhejiang University,
Hangzhou 310027, China |
|
|
DERIVATION AND INTEGRAL SLIDING MODE
VARIABLE STRUCTURE CONTROL OF HYDRAULIC
VELOCITY TRACKING SYSTEM
Abstract: The velocity tracking control of a hydraulic servo system is studied. Since the dynamics of the system are highly nonlinear and have large extent of model uncertainties, such as big changes in load and parameters, a derivation and integral sliding mode variable structure control scheme (DI-SVSC) is proposed. An integral controller is introduced to avoid the assumption that the derivative of desired signal must be known in conventional sliding mode variable structure control, a nonlinear derivation controller is used to weaken the chattering of system. The design method of switching function in integral sliding mode control, nonlinear derivation coefficient and controllers of DI-SVSC is presented respectively. Simulation shows that the control approach is of nice robustness and improves velocity tracking accuracy considerably.
Key words: Hydraulic servo system Velocity tracking Integral variable structure control
Nonlinear derivation control |