The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

S P Ghoshal - One of the best experts on this subject based on the ideXlab platform.

  • load frequency stabilization by coordinated control of thyristor controlled phase shifters and superconducting magnetic energy storage for three types of interconnected two area power systems
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Praghnesh Bhatt, S P Ghoshal
    Abstract:

    In this paper, automatic generation control with interconnected two-area multi-unit all-hydro power system and two more test systems as all-thermal and thermal-hydro mixed haves been investigated. The transfer function of hydro turbine having non-minimum phase characteristics makes it different from the steam turbine. Upon application of small load perturbation to such all-hydro system, the frequency is severely disturbed and the system eventually becomes unstable. To stabilize the system for such load disturbance, comparative transient performance of two cases as (a) Thyristor Controlled Phase Shifter (TCPS) installed in series with the tie-line in coordination with Superconducting Magnetic Energy Storage (SMES) and (b) SMES located at each terminal of both areas are analyzed. It is observed that the case (b) i.e. SMES located at each terminal of both areas suppresses the frequency oscillations more effectively in Integral Controller assisted AGC of two-area multi-unit all-hydro system and the other two systems as well. In addition, the effectiveness of proposed frequency stabilizers is guaranteed by analyzing the transient responses of the system with different system parameters, various load patterns and in the event of temporary and permanent tie-line outage. Gains of the Integral Controller in AGC loop and parameters of TCPS and SMES are optimized with the help of a relatively novel particle swarm optimization, developed by the authors, called as craziness-based particle swarm optimization (CRPSO). The optimizing performance has been compared to that of real-coded genetic algorithm (RGA) to establish its superiority.

  • load frequency stabilization by coordinated control of thyristor controlled phase shifters and superconducting magnetic energy storage for three types of interconnected two area power systems
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Praghnesh Bhatt, S P Ghoshal, Ranjit Roy
    Abstract:

    In this paper, automatic generation control with interconnected two-area multi-unit all-hydro power system and two more test systems as all-thermal and thermal-hydro mixed haves been investigated. The transfer function of hydro turbine having non-minimum phase characteristics makes it different from the steam turbine. Upon application of small load perturbation to such all-hydro system, the frequency is severely disturbed and the system eventually becomes unstable. To stabilize the system for such load disturbance, comparative transient performance of two cases as (a) Thyristor Controlled Phase Shifter (TCPS) installed in series with the tie-line in coordination with Superconducting Magnetic Energy Storage (SMES) and (b) SMES located at each terminal of both areas are analyzed. It is observed that the case (b) i.e. SMES located at each terminal of both areas suppresses the frequency oscillations more effectively in Integral Controller assisted AGC of two-area multi-unit all-hydro system and the other two systems as well. In addition, the effectiveness of proposed frequency stabilizers is guaranteed by analyzing the transient responses of the system with different system parameters, various load patterns and in the event of temporary and permanent tie-line outage. Gains of the Integral Controller in AGC loop and parameters of TCPS and SMES are optimized with the help of a relatively novel particle swarm optimization, developed by the authors, called as craziness-based particle swarm optimization (CRPSO). The optimizing performance has been compared to that of real-coded genetic algorithm (RGA) to establish its superiority.

Eduardo D Sontag - One of the best experts on this subject based on the ideXlab platform.

  • in vitro implementation of robust gene regulation in a synthetic biomolecular Integral Controller
    Nature Communications, 2019
    Co-Authors: Deepak K Agrawal, Ryan Marshall, Vincent Noireaux, Eduardo D Sontag
    Abstract:

    Feedback mechanisms play a critical role in the maintenance of cell homeostasis in the presence of disturbances and uncertainties. Motivated by the need to tune the dynamics and improve the robustness of gene circuits, biological engineers have proposed various designs that mimic natural molecular feedback control mechanisms. However, practical and predictable implementations have proved challenging because of the complexity of synthesis and analysis of complex biomolecular networks. Here, we analyze and experimentally validate a synthetic biomolecular Controller executed in vitro. The Controller ensures that gene expression rate tracks an externally imposed reference level, and achieves this goal even in the presence of certain kinds of disturbances. Our design relies upon an analog of the well-known principle of Integral feedback in control theory. We implement the Controller in an Escherichia coli cell-free transcription-translation system, which allows rapid prototyping and implementation. Modeling and theory guide experimental implementation with well-defined operational predictability. Feedback mechanisms for synthetic gene circuits are necessary to provide robustness to external perturbations. Here the authors validate a biomolecular Controller based on a sigma and anti-sigma factor to achieve stable gene expression in the face of external disturbances in an in vitro synthetic gene circuit.

  • some remarks on robust gene regulation in a biomolecular Integral Controller
    Conference on Decision and Control, 2019
    Co-Authors: Deepak K Agrawal, Ryan Marshall, Ali M Alradhawi, Vincent Noireaux, Eduardo D Sontag
    Abstract:

    Integral feedback can help achieve robust tracking independently of external disturbances. Motivated by this knowledge, biological engineers have proposed various designs of biomolecular Integral feedback Controllers to regulate biological processes. In this paper, we theoretically analyze the operation of a particular synthetic biomolecular Integral Controller, which we have recently proposed and implemented experimentally. Using a combination of methods, ranging from linearized analysis to sum-of-squares (SOS) Lyapunov functions, we demonstrate that, when the Controller is operated in closed-loop, it is capable of providing Integral corrections to the concentration of an output species in such a manner that the output tracks a reference signal linearly over a large dynamic range. We investigate the output dependency on the reaction parameters through sensitivity analysis, and quantify performance using control theory metrics to characterize response properties, thus providing clear selection guidelines for practical applications. We then demonstrate the stable operation of the closed-loop control system by constructing quartic Lyapunov functions using SOS optimization techniques, and establish global stability for a unique equilibrium. Our analysis suggests that by incorporating effective molecular sequestration, a biomolecular closed-loop Integral Controller that is capable of robustly regulating gene expression is feasible.

  • in vitro implementation of robust gene regulation in a synthetic biomolecular Integral Controller
    bioRxiv, 2019
    Co-Authors: Deepak K Agrawal, Ryan Marshall, Vincent Noireaux, Eduardo D Sontag
    Abstract:

    Feedback mechanisms play a critical role in the maintenance of cell homeostasis in the presence of disturbances and uncertainties. Motivated by the need to tune the dynamics and improve the robustness of synthetic gene circuits, biological engineers have proposed various designs that mimic natural molecular feedback control mechanisms. However, practical and predictable implementations have proved challenging because of the complexity of synthesis and analysis of complex biomolecular networks. Here, we analyze and experimentally validate a first synthetic biomolecular Controller executed in vitro. The Controller is based on the interaction between a sigma and an anti-sigma factor, which ensures that gene expression tracks an externally imposed reference level, and achieves this goal even in the presence of disturbances. Our design relies upon an analog of the well-known principle of Integral feedback in control theory. We implement the Controller in an Escherichia coli cell-free transcription-translation (TXTL) system, a platform that allows rapid prototyping and implementation. Modeling and theory guide experimental implementation of the Controller with well-defined operational predictability.

Praghnesh Bhatt - One of the best experts on this subject based on the ideXlab platform.

  • load frequency stabilization by coordinated control of thyristor controlled phase shifters and superconducting magnetic energy storage for three types of interconnected two area power systems
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Praghnesh Bhatt, S P Ghoshal
    Abstract:

    In this paper, automatic generation control with interconnected two-area multi-unit all-hydro power system and two more test systems as all-thermal and thermal-hydro mixed haves been investigated. The transfer function of hydro turbine having non-minimum phase characteristics makes it different from the steam turbine. Upon application of small load perturbation to such all-hydro system, the frequency is severely disturbed and the system eventually becomes unstable. To stabilize the system for such load disturbance, comparative transient performance of two cases as (a) Thyristor Controlled Phase Shifter (TCPS) installed in series with the tie-line in coordination with Superconducting Magnetic Energy Storage (SMES) and (b) SMES located at each terminal of both areas are analyzed. It is observed that the case (b) i.e. SMES located at each terminal of both areas suppresses the frequency oscillations more effectively in Integral Controller assisted AGC of two-area multi-unit all-hydro system and the other two systems as well. In addition, the effectiveness of proposed frequency stabilizers is guaranteed by analyzing the transient responses of the system with different system parameters, various load patterns and in the event of temporary and permanent tie-line outage. Gains of the Integral Controller in AGC loop and parameters of TCPS and SMES are optimized with the help of a relatively novel particle swarm optimization, developed by the authors, called as craziness-based particle swarm optimization (CRPSO). The optimizing performance has been compared to that of real-coded genetic algorithm (RGA) to establish its superiority.

  • load frequency stabilization by coordinated control of thyristor controlled phase shifters and superconducting magnetic energy storage for three types of interconnected two area power systems
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Praghnesh Bhatt, S P Ghoshal, Ranjit Roy
    Abstract:

    In this paper, automatic generation control with interconnected two-area multi-unit all-hydro power system and two more test systems as all-thermal and thermal-hydro mixed haves been investigated. The transfer function of hydro turbine having non-minimum phase characteristics makes it different from the steam turbine. Upon application of small load perturbation to such all-hydro system, the frequency is severely disturbed and the system eventually becomes unstable. To stabilize the system for such load disturbance, comparative transient performance of two cases as (a) Thyristor Controlled Phase Shifter (TCPS) installed in series with the tie-line in coordination with Superconducting Magnetic Energy Storage (SMES) and (b) SMES located at each terminal of both areas are analyzed. It is observed that the case (b) i.e. SMES located at each terminal of both areas suppresses the frequency oscillations more effectively in Integral Controller assisted AGC of two-area multi-unit all-hydro system and the other two systems as well. In addition, the effectiveness of proposed frequency stabilizers is guaranteed by analyzing the transient responses of the system with different system parameters, various load patterns and in the event of temporary and permanent tie-line outage. Gains of the Integral Controller in AGC loop and parameters of TCPS and SMES are optimized with the help of a relatively novel particle swarm optimization, developed by the authors, called as craziness-based particle swarm optimization (CRPSO). The optimizing performance has been compared to that of real-coded genetic algorithm (RGA) to establish its superiority.

Alexandre Seuret - One of the best experts on this subject based on the ideXlab platform.

Ranjit Roy - One of the best experts on this subject based on the ideXlab platform.

  • load frequency stabilization by coordinated control of thyristor controlled phase shifters and superconducting magnetic energy storage for three types of interconnected two area power systems
    International Journal of Electrical Power & Energy Systems, 2010
    Co-Authors: Praghnesh Bhatt, S P Ghoshal, Ranjit Roy
    Abstract:

    In this paper, automatic generation control with interconnected two-area multi-unit all-hydro power system and two more test systems as all-thermal and thermal-hydro mixed haves been investigated. The transfer function of hydro turbine having non-minimum phase characteristics makes it different from the steam turbine. Upon application of small load perturbation to such all-hydro system, the frequency is severely disturbed and the system eventually becomes unstable. To stabilize the system for such load disturbance, comparative transient performance of two cases as (a) Thyristor Controlled Phase Shifter (TCPS) installed in series with the tie-line in coordination with Superconducting Magnetic Energy Storage (SMES) and (b) SMES located at each terminal of both areas are analyzed. It is observed that the case (b) i.e. SMES located at each terminal of both areas suppresses the frequency oscillations more effectively in Integral Controller assisted AGC of two-area multi-unit all-hydro system and the other two systems as well. In addition, the effectiveness of proposed frequency stabilizers is guaranteed by analyzing the transient responses of the system with different system parameters, various load patterns and in the event of temporary and permanent tie-line outage. Gains of the Integral Controller in AGC loop and parameters of TCPS and SMES are optimized with the help of a relatively novel particle swarm optimization, developed by the authors, called as craziness-based particle swarm optimization (CRPSO). The optimizing performance has been compared to that of real-coded genetic algorithm (RGA) to establish its superiority.