Stability and robustness analysis of discrete-time fractional-piecewise-constant-order PID controller

Abstract

In the paper we propose a fractional-piecewise-constant-order PID controller and discuss the stability and robustness of a closed loop system. In stability analysis we use the transform method and include the Nyquist-like criteria. Simulations for designed controllers are performed for the second-order plant with a delay.

Keywords

• stability analysis
• fractional calculus
• control systems
• digital control