Quantitative feedback design for a variable-displacement hydraulic vane pump

In this paper the model development, problem specification, constraint formulation, and optimal feedback controller design for a variable-displacement hydraulic pump system are shown using the quantitative feedback theory (QFT) technique. Here we develop a QFT controller for a variable-displacement pump based upon a linear, parametrically uncertain model in which some of this uncertainty reflects variation in operating point-dependent parameters. After presentation of a realistic nonlinear differential equation model, the linearized model is developed and the effect of parametric uncertainty is reviewed. From this point, closed loop performance specifications are formulated and the QFT design technique is carried out. An initial feasible controller is designed, and this design is optimized via a nonlinear programming technique