Design of a PID Controller for Unstable System: A Pole-Placement Based Firefly Approach

In this paper, PID controller parameters are tuned for an unstable electronic circuit using the pole-placement technique. Firefly algorithm is also inducted for the same problem. Different performance criteria are compared. Integrated time weight square error (ITSE) gives a better-optimized response and is considered as the objective function for the algorithm. The proposed methods are then compared with the other traditional tuning techniques such as Ziegler Nichols, Chien- Hrones- Reswick and Genetic algorithm. The validity and efficiency of the pole-placement based firefly approach is verified using MATLAB simulation results. Simulation result shows that both the proposed method not only stabilizes the unstable system but also satisfies the time domain performance criteria.