Soumya Ranjan Mahapatro

Bio: Soumya Ranjan Mahapatro is an academic researcher from National Institute of Technology, Rourkela. The author has contributed to research in topics: PID controller & Control theory. The author has an hindex of 5, co-authored 10 publications receiving 63 citations. Previous affiliations of Soumya Ranjan Mahapatro include Madanapalle Institute of Technology and Science.

Design and experimental realization of a robust decentralized PI controller for a coupled tank system.

Abstract: This paper presents design and realization of a robust decentralized PI controller for regulating the level of a coupled tank system. The proposed controller is designed based on a predefined reference transfer function model in which we adopt a frequency matching of actual and reference models. Realization of control algorithms for a multivariable system is often complicated owing to uncertainties in the process dynamics. In this paper, initially a frequency response fitting model reduction technique is adopted to obtain a First Order Plus Dead Time (FOPDT) model of each higher order decoupled subsystem. Further, using the obtained reduced order model, the proposed robust decentralized PI controller is designed. The stability and performance of the proposed controller are verified by considering multiplicative input and output uncertainties. The performance of the proposed robust decentralized controller has been compared with that of a decentralized PI controller. To validate the performance of the proposed control approach, real-time experimentation is pursed on a Feedback Instrument manufactured coupled tank system.

A Robust Decentralized PID Controller Based on Complementary Sensitivity Function for a Multivariable System

Abstract: This brief presents design, development and real-time implementation of a robust decentralized PID controller based on complementary sensitivity function through a graphical tuning method for a multivariable system. ${H_{\infty }}$ criterion is adopted to find out the controller parameters of the proposed robust decentralized PI controller. To verify efficacy of the proposed controller, its performance is compared with that of other decentralized PI controllers. The proposed controller is implemented in real-time on a coupled tank liquid level system. From the simulation and experimental results obtained, it is observed that the proposed controller exhibits superior control performance over other decentralized PI controllers.

Design of a robust optimal decentralized PI controller based on nonlinear constraint optimization for level regulation: an experimental study

Abstract: This paper presents the development of a new robust optimal decentralized PI controller based on nonlinear optimization for liquid level control in a coupled tank system. The proposed controller maximizes the closed-loop bandwidth for specified gain and phase margins, with constraints on the overshoot ratio to achieve both closed-loop performance and robustness. In the proposed work, a frequency response fitting model reduction technique is initially employed to obtain a first order plus dead time ( FOPDT ) model of each higher order subsystem. Furthermore, based on the reduced order model, a proposed controller is designed. The stability and performance of the proposed controller are verified by considering multiplicative input and output uncertainties. The performance of the proposed optimal robust decentralized control scheme has been compared with that of a decentralized PI controller. The proposed controller is implemented in real-time on a coupled tank system. From the obtained results, it is shown that the proposed optimal decentralized PI controller exhibits superior control performance to maintain the desired level, for both the nominal as well as the perturbed case as compared to a decentralized PI controller.

A comparative study of two decoupling control strategies for a coupled tank system

Abstract: This paper presents a comparative study of two controllers namely Internal Model control (IMC) decoupling controller and an inverted decoupling controller applied to a coupled-tank liquid level system. These controllers are designed based on identified First Order Plus Dead Time (FOPDT) model of a coupled tank system. The performance of the two decoupling controllers are studied considering input and output multiplicative uncertainties. From the simulation and experimental studies, it is found that the inverted decoupling approach is more robust compared to IMC.

Design and experimental realization of a robust decentralized PI controller for a coupled tank system.

Abstract: This paper presents design and realization of a robust decentralized PI controller for regulating the level of a coupled tank system. The proposed controller is designed based on a predefined reference transfer function model in which we adopt a frequency matching of actual and reference models. Realization of control algorithms for a multivariable system is often complicated owing to uncertainties in the process dynamics. In this paper, initially a frequency response fitting model reduction technique is adopted to obtain a First Order Plus Dead Time (FOPDT) model of each higher order decoupled subsystem. Further, using the obtained reduced order model, the proposed robust decentralized PI controller is designed. The stability and performance of the proposed controller are verified by considering multiplicative input and output uncertainties. The performance of the proposed robust decentralized controller has been compared with that of a decentralized PI controller. To validate the performance of the proposed control approach, real-time experimentation is pursed on a Feedback Instrument manufactured coupled tank system.

A Two-Degree-of-Freedom Internal Model-Based Active Disturbance Rejection Controller for a Wind Energy Conversion System

Abstract: Active disturbance rejection control (ADRC) is a widely employed control strategy due to its ability to deal with the disturbance and parametric uncertainties. Extended state observer (ESO) serves as the core block in an ADRC. ESO estimates the lumped disturbance in the wind energy conversion system (WECS) which is then canceled by designing a suitable control law. However, for a complex system such as WECS, the exact estimation of disturbance by using ESO is difficult. To overcome this difficulty, an ADRC is designed in this paper by adopting a two-degree-of-freedom (TDF) internal model controller framework for a permanent magnet synchronous generator (PMSG)-based WECS. The setpoint and disturbance rejection filters of TDFIMC are considered as two tuning parameters instead of using the controller and observer bandwidths as tuning parameters in ADRC. The efficiency of the proposed controller to regulate the active and reactive power in the presence of parametric uncertainties and disturbance is examined by pursuing first simulation studies followed by experimentation on a 1-kW PMSG-based WECS developed in our laboratory. Both simulation and experimental results clearly show that, by employing the proposed control scheme, the steady-state and transient responses of active and reactive power transfer to the grid are enhanced. Furthermore, on comparing its performances with that of a multiloop active disturbance rejection controller (MADRC), it is also confirmed that the former exhibits superior performance.

Disturbance Observer-Based Feedback Linearization Control for a Quadruple-Tank Liquid Level System.

Abstract: A novel input/output feedback linearization control method by utilizing nonlinear disturbance observer (NDOB) is proposed for a quadruple-tank liquid level (QTLL) system in this paper. Firstly, the mathematical model of QTLL system is established by using Bernoulli’s law and mass conservation. Secondly, in view of the nonlinear and coupling characteristics of the QTLL system, a input/output feedback linearization controller is designed. Then, a NDOB is proposed to estimate disturbances and applied to compensation control. Finally, simulation and experimental results show that the proposed strategy has better control performances than PID control and the disturbance observer-based sliding mode control (DOBSMC).

Disturbance Observer-Based Feedback Linearization Control for a Quadruple-Tank Liquid Level System

Abstract: A novel input/output feedback linearization control method by utilizing nonlinear disturbance observer (NDOB) is proposed for a quadruple-tank liquid level (QTLL) system in this paper. Firstly, the mathematical model of QTLL system is established by using Bernoulli's law and mass conservation. Secondly, in view of the nonlinear and coupling characteristics of the QTLL system, a input/output feedback linearization controller is designed. Then, a NDOB is proposed to estimate disturbances and applied to compensation control. Finally, simulation and experimental results show that the proposed strategy has better control performances than PID control and the disturbance observer-based sliding mode control (DOBSMC).