Design of Fractional Order Controller Satisfying Given Gain and Phase Margin for a Class of Unstable Plant with Delay

The paper describes the design problem of fractional order controller satisfying gain and phase margin of the closed loop system with unstable plant with delay. The proposed method is based on using Bode's ideal transfer function as a reference transfer function of the open loop system. Synthesis method is based on simplify of the object transfer function. Fractional order of the controllers is relative with gain and phase margin only. Computer method for synthesis of fractional controllers is given. The considerations are illustrated by numerical example and results of computer simulation with MATLAB/Simulink.