A Software Tool for Robust PID Design

This paper presents a fast, interactive and easily modifiable software tool for robust PID design. The Matlab based program is supposed to give people with moderate knowledge on PID control a possibility to learn more and also be a future part of an autotuner. The PID design is made by minimizing the integrated absolute error value during a load disturbance on the process input. The optimization is performed with H∞ constraints on the sensitivity and complementary sensitivity function, providing a robust closed loop system. Nelder Mead optimization is used with the AMIGO method providing an initial controller. The proposed method works well, and is very efficient, on a large batch of systems common in process industry. The design tool is also shown to work on a highly oscillatory process model.