Closed loop control design for nonlinear, nonquadratic systems

Hydraulic manipulators are extensively utilized to move heavy loads in many industrial tasks. In commercial applications, a manipulator base is required to rotate a motion range of the full 360°. This is usually implemented by using a hydraulic rack and pinion gear actuator. Due to the manipulator’s long reach and heavy loads, manipulator tip acceleration can produce significant torque to the rotation gear in free-space motion. Imposed by nonlinear dynamical behavior (involving, e.g., the gear backlash and actuator friction) added to high inertia, a system closed-loop control design becomes a challenging task. An advanced closed-loop control enables to increase the automation-level of hydraulic manipulators. This study designs a novel subsystem-dynamics-based controller for a hydraulic rack and pinion gear actuator utilizing the control design principles of the virtual decomposition control (VDC) approach. An adaptive backlash compensation is incorporated in the control design. Furthermore, the proposed controller is implemented in previously-designed state-of-the-art hydraulic manipulator control. The stability of the overall control design is proven. Experiments with a full-scale commercial hydraulic manipulator demonstrate the effectiveness of the proposed adaptive backlash compensation and the overall control performance.

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RUPERT closed loop control design

2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society ◽

10.1109/iembs.2008.4649952 ◽

2008 ◽

Cited By ~ 6

Author(s):

Sivakumar Balasubramanian ◽

Ruihua Wei ◽

Jiping He

Keyword(s):

Closed Loop ◽

Control Design ◽

Closed Loop Control ◽

Loop Control

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Model-Based Control Design of Series Resonant Converter Based on the Discrete Time Domain Modelling Approach for DC Wind Turbine

Journal of Renewable Energy ◽

10.1155/2018/7898679 ◽

2018 ◽

Vol 2018 ◽

pp. 1-18 ◽

Cited By ~ 3

Author(s):

Yu-Hsing Chen ◽

Catalin Gabriel Dincan ◽

Philip Kjær ◽

Claus Leth Bak ◽

Xiongfei Wang ◽

...

Keyword(s):

Discrete Time ◽

Time Domain ◽

Closed Loop ◽

Control Structure ◽

Control Design ◽

Closed Loop Control ◽

Resonant Converter ◽

Loop Control ◽

Series Resonant ◽

Domain Modelling

This paper focuses on the modelling of the series resonant converter proposed as a DC/DC converter for DC wind turbines. The closed-loop control design based on the discrete time domain modelling technique for the converter (named SRC#) operated in continuous-conduction mode (CCM) is investigated. To facilitate dynamic analysis and design of control structure, the design process includes derivation of linearized state-space equations, design of closed-loop control structure, and design of gain scheduling controller. The analytical results of system are verified in z-domain by comparison of circuit simulator response (in PLECS™) to changes in pulse frequency and disturbances in input and output voltages and show a good agreement. Furthermore, the test results also give enough supporting arguments to proposed control design.

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