JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, cilt.19, sa.1, ss.9-19, 2016 (ESCI)
In this study, wireless temperature control experiments were achieved using three different parameter tuning methods which using PID control algorithm is applied to a process simulator. Under the same conditions, results taken from the wireless experiments performed for three different set points were compared. To achieve the data transfer between computer in Process Control Laboratory and the simulator in Unit Operations Laboratory, wireless communication system established. Wireless experiments were performed on-line by means of MATLAB/Simulink program. Wireless data transfers during the experiments were carried out using radio waves at a frequency of 2.4 GHz. For the dynamics experiments performed employing Cohen-Coon and Ziegler-Nichols methods, the process reaction curve was prepared using step change effect. The dead time, time constant and gain values were determined as 33s, 367s and 0.4, respectively. K-C, tau(I), tau(d) coefficients are determined by Cohen-Coon as 37.7, 78.3s, 11.8s, respectively. Comparing the experimental results performed at different set points, one could see that the heater works irregularly and on-off form during the experiments. It is noted that the coefficients obtained with this method are not effective for temperature control. The K-C, tau(I), tau(d) parameters are determined by the Ziegler-Nichols method as 0.412, 66.0, 16.5s, respectively. In this control case, the temperature followed the desired set point with 1 degrees C offset. By using trial and error method, K-C, tau(I), tau(d) parameters are obtained as 0.21, 20.0, 4.5s, respectively. By this control method, temperature followed the desired set point without any offset and wireless temperature control was achieved successfully for different set points.