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Vol: 48(62) No: 1 / March 2003      

Computer Aided Design of Two-Degree-Of-Freedom (2DF) Controllers
Zs. Preitl
Department of Automation and Applied Informatics, Budapest University of Technology and Economics, MTA-BME Control Research Group, H-1111, Budapest, Goldmann Gy. tér 3., Hungary, e-mail: preitl@avalon.aut.bme.hu
T. Levendovszky
Department of Automation and Applied Informatics, Budapest University of Technology and Economics, MTA-BME Control Research Group, H-1111, Budapest, Goldmann Gy. tér 3., Hungary, e-mail: tihamer@avalon.aut.bme.hu


Keywords: 2DF controller, CAD method, MATLAB program, PID controller, sensitivity analysis.

Abstract
The use of two-degree-of-freedom (2DF) controllers is justified when good performance is required both concerning servo and disturbance rejection. The paper presents main ides regarding design aspects and a CAD methodology and program for 2DF controller. Connections between 2DF and conventional controllers with additional filters are presented. An example compares the performances that can be achieved using a 2DF controller and a classical PID controller. The sensitivity of the control structure is studied based on possible modifications of the plant’s parameters.

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