SELF-TUNING OF AN INTERVAL TYPE-2 FUZZY PID CONTROLLER FOR A HEAT EXCHANGER SYSTEM

Document Type : Research Paper

Authors

1 Dept. of Instrumentation and Automation Engineering, Shiraz University, Shiraz, I. R. of Iran

2 Faculty of Advanced Technologies, Nano Chemical Engineering Dept., Shiraz University, Shiraz, I. R. of Iran

Abstract

A novel technique is investigated for PID controller adaptation in order to control the
temperature of a liquid-phase reactor tank by using a heat exchanger system. As for nonlinearity,
time delay problems and model uncertainties introduced by the heat exchanger, an interval type-2
fuzzy system (IT2FS) is implemented to enhance and improve the total control performance.
Moreover, the fuzzy inference rules which enable the adaptive adjustment of PID parameters are
established based on error and error variations. Target tracking, oscillation control and error
evaluation for the proposed controller are compared with previously performed control strategies
on the mentioned heat exchanger system. The results show that the adaptive technique for PID
gain based on IT2FS has lower error and strengthened capacity for external oscillation control and
also an acceptable tracking capability.

Keywords