The performance analysis of PID controller with setpoint filter and anti integral Windup for a FOPDT thermal process

The aim of this paper is to improve performance and to reduce peak overshoot of a thermal process. Set point filter is widely used for reducing peak overshoot in various procees. There are different anti integral windup methods such as back calculation and conditional integration are used for eliminating integral windup action, which improves system performance. For achieving the advantage of set point filter and anti integral windup strategy, a newly proposed method of set point filter based anti integral windup PID controller with integral state predictor is used in thermal process. PID controller is used in a process, due to integral windup phenomenon, performance degradation and large peak overshoot will appear. The steady state value of integral state is predicted while PID controller output is saturated and its value is utilized as initial value of integral state when PID controller begins to operate in a linear range. Set point filter is designed by using peak overshoot and peak time of system response. The proposed method is applied on FOPDT transfer function of a thermal process and studied using MATLAB Simulink tool. The Simulation results shows that performance of the process is improved and peak overshoot is reduced.