Indirect optimal tuning rules for fractional order proportional integral derivative controller

What is it about?

In this article, new optimal tuning rules for the Fractional order PID controller are proposed, the plant is shifted in the frequency domain using the shifting parameter ψ.. The proposed tuning rules are derived with the help of the Indirect Design approach. Two simulations and one experiment of level control of the Canonical tank system are used to show the effectiveness of the proposed tuning rule. With the help of simulation and experimental data, it is shown that the robustness of the FOPID controller can be modified with the help of the shifting constant ψ. Gain Margin and the Phase margin of the controller increases with the increase in the constant ψ and viceversa. The proposed work is been compared with the five existing methods. Additionally, it is shown that the FOPID controller design follows the theory of IDA-1, which opens a new dimension in the FOPID controller design fields

Featured Image

Photo by RephiLe water on Unsplash

Photo by RephiLe water on Unsplash

Why is it important?

The tuning rules of stochastically optimized fractional order PID controllers exist in the literature for the fixed values of maximum sensitivity. Maximum Sensitivity or robustness of the process is application-dependent. Due to complex fractional order mathematics, the design of fractional order PID controller is complex. Therefore, in this article, new optimal tuning rules for FOPID controller are proposed using the shifted version of the plant. The adjustable robustness is achieved by varying tuning variable ψ which has a linear relation with the Maximum Sensitivity, Gain margin and Phase Margin. The range of ψ within which it can be varied is also proposed for both stable and unstable processes.

Perspectives