This paper presents the implementation of fractional order PID (FO-PID) controller using hardwired modules of constant phase element (CPE). A new approach of phase shaping by slope cancellation of asymptotic… Click to show full abstract
This paper presents the implementation of fractional order PID (FO-PID) controller using hardwired modules of constant phase element (CPE). A new approach of phase shaping by slope cancellation of asymptotic phase plots for zeros and poles within the given bandwidth is realized. Analog circuits, which exhibit analog fractional-order integrator and fractional-order differentiator, are used for building the FO-PID controller. The design procedure is developed to obtain the optimal pole–zero pairs and respective “Fractance” components to realize for any value of fractional differ-integrator. These CPE elements give minimum error tolerance over the set phase value by using commercially available (R–C) components and Op-Amps. The pole–zero location in the root locus plot with constant asymptotic angle under various feed-forward gains is achieved with these analog integrodifferential circuits of the FO-PID. The iso-damping feature of the controller is practically demonstrated. A comparative performance is demonstrated under various settings of feed forward gains, which indicate the constant overshoot with FO-PID against the conventional PID. These circuits are developed and implemented with a DC motor emulator to confirm the designed performance of the controller.
               
Click one of the above tabs to view related content.