Existence & uniqueness of consistent conjectural variation equilibrium in electricity markets

The real electricity markets are usually oligopoly, where market suppliers (generators) will have some market power and can adopt strategic bidding strategies for maximum profits. Generally, the game-theory based methods are the natural way to analyze the market equilibrium and study the strategic behaviors. As a widely studied method in game theory, the conjecture variation technique is reported to model the strategic behavior in deregulated electricity markets recently. Unfortunately, the conjecture variation models have been criticized for the drawback of logical inconsistence and abundant equilibria. Aim for this, the existence and uniqueness of consistent conjectural variation equilibrium in the electricity markets are investigated. Due to some good characteristics of electricity markets and using an infinite horizon optimization model, it is shown that the consistent conjecture variation will satisfy a coupled nonlinear equation system and there is only one equilibrium. © 2005 IEEE.published_or_final_versio

Control theory application in power market stability analysis

This paper proposes a new framework to model the system dynamics and study the system stability for the quantity bidding competition in power market. From the viewpoint of control theory, the quantity bidding competition is modeled as close-loop dynamic system, where market price is the system feedback signal. Based on the objective of maximizing individual profit in a shot-game, a general dynamic process is given to describe supplier's adjustment behavior, which can be used to model all classical bidding strategy and CV-based bidding strategy. With the application of control theory, sufficient stability conditions and market equilibrium are presented. Computer test results support the analytic conclusion very well.published_or_final_versio

On the tortuosity factor of solid phase in solid oxide fuel cell electrodes

2014-2015 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

A novel ANN fault diagnosis system for power systems using dual GA loops in ANN training

Fault diagnosis is of great importance to the rapid restoration of power systems. Many techniques have been employed to solve this problem. In this paper, a novel Genetic Algorithm (GA) based neural network for fault diagnosis in power systems is suggested, which adopts three-layer feed-forward neural network. Dual GA loops are applied in order to optimize the neural network topology and the connection weights. The first GA-loop is for structure optimization and the second one for connection weight optimization. Jointly they search the global optimal neural network solution for fault diagnosis. The formulation and the corresponding computer flow chart are presented in detail in the paper. Computer test results in a test power system indicate that the proposed GA-based neural network fault diagnosis system works well and is superior as compared with the conventional Back-Propagation (BP) neural network.published_or_final_versio

Available transfer capability calculation with post-contingency generation rescheduling/load curtailment

The available transfer capability (ATC) is an important index indicating the remaining transfer capability in the physical transmission network for further commercial activity above existing commitments. In this paper, ATC mathematical model considering post-contingency generation rescheduling and load curtailment is first formulated. Benders decomposition method is then used to partition the ATC model above into a base case master problem and a series of independent subproblems relevant to various contingencies. Finally, an improved parallel solution scheme is employed to improve the convergence. Numerical results on a 4-bus test system show clearly the effectiveness of the presented method and necessity of considering post-contingency generation rescheduling and load curtailment in calculating ATC.published_or_final_versio

A novel radial basis function neural network for fault section estimation in transmission network

In this paper, the application of Radial Basis Function Neural Network (RBF NN) to fault section estimation in power systems is addressed. The orthogonal least square algorithm has been extended to optimize the parameters of RBF NN. In order to assess the effectiveness of RBF NN, a classical Back-Propagation Neural Network (BP NN) has been developed to solve the same problem for comparison. Computer test is conducted on a 4-bus test system and the test results show that the RBF NN is quite effective and superior to BP NN in fault section estimation.published_or_final_versio

Framework design of a general-purpose power market simulator based on multi-agent technology

Power system deregulation has become a worldwide trend which introduces competition in power system in order to realize efficient electricity production and investment. In this regard, power market simulator will be a useful tool to study bidding strategies, market operation and market power and to train market operators. In this paper, the framework design of a novel power market simulator based on the state-of-the-art multi-agent technology is suggested and described in detail, which is the first phase in developing a general-purpose power market simulator.published_or_final_versio

Distributed strain sensor networks for in-construction monitoring and safety evaluation of a high-rise building

2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordOthersP0000033, G-U845Publishe

Developing a voltage-stability-constrained security assessment system part I: Determination of power system voltage security operation limits

The method for determining the voltage security operation limits in a practical voltage security analysis (VSA) system based on VSAT software for large power systems is introduced in this paper. These operation limits include bus voltage limits, branch/corridor transfer power limits and P-load limit of the whole system. The voltage security operation limits are determined by the most critical contingency among the studied contingency set. The most critical contingency determines the P-load limit of the whole system, and all kinds of operation parameter limits are operation parameter values corresponding to this P-load limit under pre-contingency. An operation parameter limit is upper limit if the function relationship between this operation parameter and load power is an increasing curve, or lower limit if the function relationship between this operation parameter and load power is an decreasing curve. These operation parameter limits are helpful for operators to monitor the system operation state. © 2005 IEEE.published_or_final_versio

Developing a voltage-stability-constrained security assessment system part II : Structure and function design and technology used

This is the second part in a two-part paper on the development of a voltage stability constrained security assessment system (VSC-SAS). In this part, overall VSC-SAS structure and function design and technology used will be presented. The system is expected to be used in both on-line and off-line modes. In on-line mode, on-line SCADA/EMS data will be used for VSC-SAS use; while in off-line mode (usually day-ahead calculation), historical data can be used for VSC-SAS. Both results (i.e. system operation limits) can be selected to compare with real time operation conditions and supervision power system operation security margin. © 2005 IEEE.published_or_final_versio