Distributed Control System Applied in Temperatur Control by Coordinating Multi-loop Controllers
Edi Rakhman, Feriyonika Feriyonika
In Distributed Control System (DCS), multitasking management has been important issues continuously researched and developed. In this paper, DCS method is applied in temperature control system by coordinating three single loop sub-controllers (fan velocity [PI-controller], position of window [P-controller], and local temperature control [PID-controller]). In the proposed method, the sub-controllers are firstly designed by using Ziegler-Nichols and tuning rule method, which are then coordinated by master controller based on condition of global error and set point. The result shows that with Kp=11.2 and Ti=5 for fan velocity controller, Kp=50 for position of window controller, and Kp=7.5, Ti=33.56, Td=8.39 for local temperature controller, the master control could distribute the set points to sub-controllers so that the temperature response could successfully follow the global temperature set point with 11.96%, 188 second, and 570.4 second for the maximum overshoot, rise time and settling time, respectively. Confirmation experiment is conducted to verify the proposed method. The method can be potentially applied in industry due to simplicity in master control algorithm and presence of PID which has been generally included in today industrial equipments.
Distributed Control System; PID; Ziegler-Nichols; multi-loop PID controllers.