The Experts below are selected from a list of 336987 Experts worldwide ranked by ideXlab platform

W.g. Price - One of the best experts on this subject based on the ideXlab platform.

  • A Power Flow mode theory based on a system's damping distribution and Power Flow design approaches
    Proceedings of the Royal Society A: Mathematical Physical and Engineering Sciences, 2005
    Co-Authors: Yeping Xiong, Jing Tang Xing, W.g. Price
    Abstract:

    A Power Flow mode theory is developed to describe the natural Power Flow behaviour of a dynamic system based on its inherent damping distribution. The system9s characteristic-damping matrix is constructed and it is shown that the eigenvalues and eigenvectors of this matrix identify natural Power Flow characteristics. These eigenvectors, or Power Flow mode vectors, are chosen as a set of base-vectors spanning the Power Flow space and completely describe the Power Flow in the system. The generalized coordinate of the velocity vector decomposed in this space defines the Power Flow response vector. A time-averaged Power Flow expression and theorems relating to its estimation are presented. Based on this theory, Power Flow design approaches are proposed to identify energy Flow patterns satisfying vibration control requirements. The mode control factor defines the measure of the correlation between a Power Flow mode and a natural vibration mode of the system. Power Flow design theorems are presented providing guidelines to construct damping distributions maximizing Power dissipation or to suppress/retain a particular vibration mode and/or a motion. The developed damping-based Power Flow mode theory is compared with a mobility-based Power Flow model. It is shown that the proposed Power Flow model provides insight into the Power Flow dissipation mechanisms in dynamic systems. Examples are presented to demonstrate the applicability of the Power Flow mode theory and the Power Flow design approach. These examples demonstrate the generality of the theory, including non-symmetric damping matrices, and illustrate Power Flow design applications through modifications of the system9s damping distribution using passive and/or active control components.

  • A novel method for Power Flow design and control based on Power Flow mode theory
    2005
    Co-Authors: Yeping Xiong, Jing Tang Xing, W.g. Price
    Abstract:

    In a previous study, a generalized Power Flow mode theory was proposed to describe the Power Flow behaviour of a dynamical system based on the inherent characteristics of the system’s damping distribution. By extending this theory, a Power Flow design and control mathematical model is developed which allows control of energy Flow patterns, thus reducing or retaining vibratory energy Flow in a particular vibration mode of the system. This is achieved through analyzing energy Flow characteristics and designing an appropriate damping distribution in the system to adjust its characteristic damping factors and Power Flow mode vectors. To meet different vibration control requirements, new design criteria are proposed so as to dissipate maximum vibration energy and/or to control Power Flow in a specific vibration mode of the system. This mathematical model is demonstrated through an example of a suspension system with two degrees of freedom for which the Power Flow dissipation corresponding to selected control cases are presented. This study provides a novel approach to design a dynamical system from the perspective of energy Flow patterns.

Khairul Nisak Md Hasan - One of the best experts on this subject based on the ideXlab platform.

  • Application of particle swarm optimization and its variants to Interline Power Flow Controllers and optimal Power Flow
    2010 International Conference on Intelligent and Advanced Systems, 2010
    Co-Authors: Khalid. H. Mohamed, K. S. Rama Rao, Khairul Nisak Md Hasan
    Abstract:

    In this paper, three types of particle swarm optimization techniques, namely basic particle swarm optimization, inertia weight approach particle swarm optimization and constriction factor approach particle swarm optimization are applied to optimal Power Flow control of an electrical Power system incorporating Interline Power Flow Controller. Based on the steady state model, the sizing of the controller in the network is formulated as an optimization problem to minimize the transmission line loss. The Power Flow control constraints of the controller are included in optimal Power Flow problem in addition to the normal conventional constraints. The simulation results on standard IEEE 14-bus system minimizing the transmission line losses show the effectiveness of the variants of particle swarm optimization. The optimal control parameters of interline Power Flow controller are compared.

  • Optimal Power Flow and interline Power Flow controllers using particle swarm optimization technique
    TENCON 2009 - 2009 IEEE Region 10 Conference, 2009
    Co-Authors: Khalid. H. Mohamed, K. S. Rama Rao, Khairul Nisak Md Hasan
    Abstract:

    This paper presents an optimal Power Flow control in an electrical Power system incorporating Interline Power Flow Controller (IPFC) and using the Particle Swarm Optimization (PSO) technique. Based on the steady state model, the sizing of the IPFC controller in the network is formulated as an optimization problem to minimize the transmission line loss in the network. The Power Flow control constraints due to the use IPFC is included in optimal Power Flow (OPF) problem in addition to the normal conventional constraints.

X.p. Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Robust modeling of the interline Power Flow controller and the generalized unified Power Flow controller with small impedances in Power Flow analysis
    Electrical Engineering, 2006
    Co-Authors: X.p. Zhang
    Abstract:

    The interline Power Flow controller (IPFC) and the generalized unified Power Flow controller (GUPFC) are two innovative configurations of the convertible static compensator (CSC) of FACTS. In this paper, direct modeling of the practical series or/and shunt operating inequality constraints of the IPFC and the GUPFC in Power Flow calculations are presented. Special initialization of a solution with the IPFC and GUPFC is also derived. Furthermore, an impedance compensation technique is proposed to deal with the numerical instability or the numerical difficulty of the IPFC and GUPFC models when either their coupling transformer impedances are too small or they are transformer-less controllers. Condition number analysis of the Newton Power Flow equations is given to get insights of the numerical instability of the voltage sourced models of the IPFC and GUPFC with small impedances. Numerical examples are given based on the IEEE 118-bus system, IEEE 300-bus system and a large scale system with 1000-buses.

  • Unified Power Flow controller models for three-phase Power Flow analysis
    Electrical Engineering, 2006
    Co-Authors: X.p. Zhang
    Abstract:

    In this paper, three models of the unified Power Flow controller (UPFC) suitable for three-phase Power Flow analysis in polar coordinates are presented. The symmetrical components control model can be used to control the positive-sequence voltage of the shunt bus and the total three-phase active and reactive Power Flows of the transmission line while the injected shunt voltages and the series voltages are balanced, respectively; the general three-phase control model can be used to control the three shunt phase voltages and the six independent active and reactive Power Flows of the transmission line; the hybrid control model can be used to control the positive-sequence voltage of the shunt bus and the six independent active and reactive Power Flows of the transmission line. The proposed UPFC models were successfully implemented in a three-phase Newton Power Flow algorithm in polar coordinates. In the implementation of these UPFC models, transformers of some common connection types, which connect the UPFC with the network, are explicitly represented. Numerical results based on a five-bus system and the modified IEEE 118-bus system are given to illustrate the UPFC control models and demonstrate the computational performance of the three-phase Newton Power Flow algorithm.

J. Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Application of Interline Power Flow Controller to ATC Enhancement by Optimal Power Flow Control
    2007 IEEE Lausanne Power Tech, 2007
    Co-Authors: J. Zhang, Akihiko Yokoyama
    Abstract:

    The latest generation of FACTS devices, namely the interline Power Flow controller (IPFC), is the combination of multiple series compensators, which are very effective in controlling Power Flows in transmission lines. In this paper, the evaluation of the impact of the IPFC on available transfer capability (ATC) enhancement is presented. An ATC computation method based on the optimal Power Flow (OPF) control is formulated to evaluate the Power transfer capability from the specified generation unit to the specified load. The IPFC, represented by its Power injection model, is incorporated into the OPF control formulation. The effectiveness of the IPFC control is demonstrated clearly by numerical simulations on a 2-machine 4-bus system and a 6-machine 22-bus system. The results are also compared with those of the unified Power Flow controller (UPFC) in various aspects.

  • Optimal Power Flow Control for Congestion Management by Interline Power Flow Controller (IPFC)
    2006 International Conference on Power System Technology, 2006
    Co-Authors: J. Zhang
    Abstract:

    The interline Power Flow controller (IPFC) is the latest generation of flexible AC transmission systems (FACTS) devices which can be used to control Power Flows of multiple transmission lines. This paper presents an optimal Power Flow (OPF) control in electric Power systems incorporating IPFC. The injection models of both the IPFC and the transmission lines embedded with IPFC, which can be easily incorporated in load Flow programs and optimal Power Flow programs, are developed. Numerical examples demonstrated that IPFC can be used for congestion management and total active Power loss minimization in electric Power systems at the same time. The minimum capacity of the IPFC converters is determined in the optimization process simultaneously.

  • A Comparison between the UPFC and the IPFC in Optimal Power Flow Control and Power Flow Regulation
    2006 38th North American Power Symposium, 2006
    Co-Authors: J. Zhang, Akihiko Yokoyama
    Abstract:

    This paper presents a comparison study between the applications of the unified Power Flow controller (UPFC) and the interline Power Flow controller (IPFC) in optimal Power Flow (OPF) control. The Power injection models of the flexible AC transmission systems (FACTS) devices are reviewed and incorporated in the OPF problem without active Power generation redispatching, which minimizes the overall generating cost. The FACTS devices are planned for Power Flow regulation and their additional degrees of freedom act as additional potential in optimizing the Power system. The performance of the UPFC and the IPFC is compared from the viewpoint of the total active Power losses and their necessary capacities through numerical examples. The feasibility of a gradient-based algorithm, namely sequential quadratic programming (SQP), is tested, and the importance and some techniques of proper selection of the initial optimization conditions are also presented.

Yeping Xiong - One of the best experts on this subject based on the ideXlab platform.

  • A Power Flow mode theory based on a system's damping distribution and Power Flow design approaches
    Proceedings of the Royal Society A: Mathematical Physical and Engineering Sciences, 2005
    Co-Authors: Yeping Xiong, Jing Tang Xing, W.g. Price
    Abstract:

    A Power Flow mode theory is developed to describe the natural Power Flow behaviour of a dynamic system based on its inherent damping distribution. The system9s characteristic-damping matrix is constructed and it is shown that the eigenvalues and eigenvectors of this matrix identify natural Power Flow characteristics. These eigenvectors, or Power Flow mode vectors, are chosen as a set of base-vectors spanning the Power Flow space and completely describe the Power Flow in the system. The generalized coordinate of the velocity vector decomposed in this space defines the Power Flow response vector. A time-averaged Power Flow expression and theorems relating to its estimation are presented. Based on this theory, Power Flow design approaches are proposed to identify energy Flow patterns satisfying vibration control requirements. The mode control factor defines the measure of the correlation between a Power Flow mode and a natural vibration mode of the system. Power Flow design theorems are presented providing guidelines to construct damping distributions maximizing Power dissipation or to suppress/retain a particular vibration mode and/or a motion. The developed damping-based Power Flow mode theory is compared with a mobility-based Power Flow model. It is shown that the proposed Power Flow model provides insight into the Power Flow dissipation mechanisms in dynamic systems. Examples are presented to demonstrate the applicability of the Power Flow mode theory and the Power Flow design approach. These examples demonstrate the generality of the theory, including non-symmetric damping matrices, and illustrate Power Flow design applications through modifications of the system9s damping distribution using passive and/or active control components.

  • A novel method for Power Flow design and control based on Power Flow mode theory
    2005
    Co-Authors: Yeping Xiong, Jing Tang Xing, W.g. Price
    Abstract:

    In a previous study, a generalized Power Flow mode theory was proposed to describe the Power Flow behaviour of a dynamical system based on the inherent characteristics of the system’s damping distribution. By extending this theory, a Power Flow design and control mathematical model is developed which allows control of energy Flow patterns, thus reducing or retaining vibratory energy Flow in a particular vibration mode of the system. This is achieved through analyzing energy Flow characteristics and designing an appropriate damping distribution in the system to adjust its characteristic damping factors and Power Flow mode vectors. To meet different vibration control requirements, new design criteria are proposed so as to dissipate maximum vibration energy and/or to control Power Flow in a specific vibration mode of the system. This mathematical model is demonstrated through an example of a suspension system with two degrees of freedom for which the Power Flow dissipation corresponding to selected control cases are presented. This study provides a novel approach to design a dynamical system from the perspective of energy Flow patterns.