Reformulated tangent method of various PID controller tuning for air pressure control

The optimum proportional(P), integral(I) and derivative(D) constants can be estimated using tangent method and proper tuning rule for process stability. The purpose of this paper is to compare the performance of various controller tuning methods for controlling the process of air pressure control trainer model SOLTEQ SEl2l. The simplest open loop test on actual plant has been performed using a new Reformulated Tangent Method (RTM). The optimum PID value is set to the real plant based on Ziegler-Nichols (ZN), Chien-Hrones-Reswick (CHR) and Chien et. al. (Chien) tuning rules. The PID Tuner software is used to simulate the response to be compared with the real plant response. The plant is connected to a Yokogawa Centum CS 3000 R3 Distributed Control System (DCS). The performance of each method is analyzed in term of percent overshoot(%OS) settling time(T_s), rise time(T_r) and integral absolute error(IAE).