PERANCANGAN KENDALI PID BERDASAR TANGGAPAN FREKUENSI UNTUK TINGGI PERMUKAAN AIR BERBASIS PLC

This study aims to examine how the frequency response Bode diagrams can be used as a PID controller to control the water levels based on PLC. Frequency response method and the seat of the root, which are core theory of the physical controllers, will bring a stable system and meet performance requirements set which is almost balanced. Plant which is used in this study is the water surface elevation system. Control algorithm, which is installed in the PLC TSX 3722, is using PL7 Pro software. The test in this study is done with a response giving to unit step. Parameters of analysis used is the reaching speed to the set-point (settling time), and overshoot. The analysis show the performance of PID based on system frequency response through Bode diagram. To determine the characteristics of water surface level control, we used the open loop control test, so we got the rise time (Tr), settling time (Ts), and the time constant ( ). The results of the test show that we know the value of transfer function which is used to determine the value of Kp, Ki and Kd to get the more efficient control system. The frequency response method using Bode diagram, can also be used to determine the PID controller with produced the stable system and error in the steady state as expected and fast response. After getting the response of a stable system, will be analyzed through Bode diagram for comparison in the modeling system. The results will be analyzed, design of PID control with frequency response generates a more efficient feedback system to control the water surface level system. With the value of Kp = 10, Ki = 0.1, and Kd = 75, we will get a more efficient system, with the efficiency ratio is 375% compared to previous method.