New approach of series-PID controller design based on modern control theory: Simulations and real-time validation

Abstract

This paper proposed a novel approach to designing the series-proportional–integral derivative (series-PID) controller, which provides desired performance specifications. In this approach, the design of the series-PID controller is carried out by modern control theory, which is based on the Butterworth pattern of pole placement, and classical control theory, which is based on Krishnamurthi’s corollary on the Routh criterion. The uniqueness of the proposed approach in comparison with existing methods is that it comprises both classical and modern control theory for improving performance and robustness trade-off. The validation of the proposed control theory is carried out using numerical examples (Linear & Non-linear models). The results show that the performance is improved compared to the existing results. The main aim of the paper is that the proposed theory should be industrial-friendly. In view of this, the proposed theory is validated on the D.C. servo motor and power system problem of load frequency control. For these practical problems, comparisons are carried out with well-known control approaches, such as the internal model control approach proposed by various authors. Finally, the proposed approach has been implemented and validated on the hardware setup of the DC–DC buck converter ($DDB{C}_c$). In numerical examples and practical problems, the efficacy of the proposed approach has been checked by robustness analysis and fragility analysis. Further, it has also been checked by determining various performance indices such as Integral Square Error (ISE), Integral Absolute Error (IAE), and Total Variations (TV).