Indirect Extended Forced Oscillation Method For PID Controller Design

In this article, an Indirect PID autotuning method is proposed with the extended forced oscillation method and Indirect Design Approach-2. In the proposed design an Ideal relay with fractional-order systems is used to generate sustained oscillations, that help in determining the ultimate frequency and gain. These parameters are further used to design the PID controller with the Indirect Design Approach 2 (IDA-2) method. The IDA2 method allows the fine tuning of the process response with the IDA2 shifting constant. It is shown that the shifting constant tunes the transient and frequency domain performance and has a monotonic relation with the phase margin. The proposed method is validated with the help of two MATLAB Simulation Examples.