Power transfer allocation for open access using graph theory - fundamentals and applications in systems without loopflow

In this paper, graph theory is used to calculate the contributions of individual generators and loads to line flows and the real power transfer between individual generators and loads that are significant to transmission open access. Related lemmas are proved which present necessary conditions required by the method. Based on ac load flow solution a novel method is suggested which can decide downstream and upstream power flow tracing paths very fast and calculate the contribution factors of generations and loads to the line flows efficiently. The power transfer between generators and loads can also be determined. The suggested method is suitable for both active and reactive power tracings of real power systems.published_or_final_versio

A kernel-oriented algorithm for transmission expansion planning

With deregulation sweeping all over electrical systems around the world, transmission planning has undergone dramatic changes during this decade. Centralized cost allocation methods have become obsolete and new procedures are needed to deal with intelligent and self-sufficient players. In this paper we study the allocation of transmission costs in a decentralized manner. For this purpose we have developed a multi-agent system that is based on a well known cooperative game theory procedure, the kernel. Using our approach, the agents are able to form kernel-stable coalitions and the cost allocation procedure is performed at every step of the kernel- algorithm. A six bus example and an IEEE 24 bus case illustrate our model. © 2000 IEEE.published_or_final_versio

Evaluation of generation expansion investment under competitive market environment

This paper proposes a new approach of generation expansion planning and its risk assessment under the competitive market environment. Different from the traditional probabilistic production costing (PPC) method under monopoly environment which is based on the deterministic generator loading priority list, the uncertainties of biddings for long-term contracts in electricity market are introduced into the new model. Based on the probability distribution of the surplus on bidding price over marginal cost, the distribution of expected generated energy for a given period can be achieved to calculate the profit of a generator. In order to manage the risks of the investment on generation expansion project, a risk assessment tool called Conditional Value at Risk (CVaR) is used. It gives the investors an intuitionistic criterion for making investment decision. A numerical example is given in this paper to valid the method. ©2005 IEEE.published_or_final_versio

Coalition formation in transmission expansion planning

The study of a decentralized coalition formation scheme in a specific power systems transmission expansion scenario is the purpose of this paper. We define first who are the agents in the expansion game and provide a decentralized coalition scheme based on Bilateral Shapley values. Finally, we allocate the total costs of expansion amongst the agents, based on the coalition history, and we compare our method with a centralized scheme.published_or_final_versio

Risk assessment of generation investment

Session 15: Paper 2This paper proposes an improved approach to risk assessment of generation investment in the new deregulated environment using the option pricing theory. A more realistic model for electricity price in the application of real option pricing method for generation asset valuation is proposed, which takes into account its fluctuation and uncertainties, and, more importantly, its daily, weekly and annual cyclic patterns, which is a unique characteristic of electricity price. Base on such a price process, the generation asset can be evaluated by the application of real option method. In order to manage the risks of the investment on generation expansion project, risk assessment tools such as Value at Risk (VaR) and Conditional Value at Risk (CVaR) may be used to provide the investors with tools for more informed decisions. A numerical example is given to illustrate the proposed method.postprintThe 15th Power Systems Computation Conference (PSCC'05), Liege, Belgium, 22-26 August 2005. In Proceedings of 15th PSCC, 2005, p. 1-

A game-theoretic model of private power production

Private power production has sprung up all around the world, especially in developing countries with rapidly increasing demands and shortage of finance. BOT arrangements have emerged as one of the most important options of private power production. Based on oligopoly theory, this paper proposes a Stackelberg game model between a BOT company and a utility where they negotiate a long-term energy contract. It is assumed that a host utility purchases electricity from a BOT company at its "avoided cost", and sells its electricity to end users at its average cost. Taking asymmetric pricing into account, our Stackelberg game model is transferred into a two-level optimization problem, and is then solved by an iterative algorithm.published_or_final_versio

China's future in electric energy

The developments and future challenges in generation, transmission, and the market aspects of electric energy systems in China are described. The Three Gorges project developed by China has started generating power, and interconnected national grid has formed, and the industry has been fundamentally restructured. The greatest challenge in the restructuring of China's power industry is to ensure that the market rules send the right signals to ensure a proper level of generation investment. China need to take a leadership role in future technology R&D in all aspects, including clean energy development and efficient energy utilization with state-of-the-art power electronics and information technologies.published_or_final_versio

Cost-benefit analysis of BOT power plants

Among nonutility generation, the build-operate-transfer (BOT) arrangement has emerged as the dominant form of private investment. Pricing nonutility generation at its avoided cost is the breakeven point for the utility in the cost-benefit analysis. In this paper, a method of calculating the breakeven cost to the utility for BOT plants whose contract lasts for 10-25 years is proposed. The proposed approach requires the computation of production costs from long-term generation expansion planning (GEP). To facilitate the inclusion of constraints introduced by BOT plants in GEP, a genetic algorithm approach is utilized in GEP. The breakeven cost is a useful measure in cost-benefit analysis of BOT power plants. An example is presented to illustrate cost-benefit analysis of BOT plants using the concept of breakeven cost.published_or_final_versio

A smoothing SQP method for nonlinear programs with stability constraints arising from power systems

This paper investigates a new class of optimization problems arising from power systems, known as nonlinear programs with stability constraints (NPSC), which is an extension of ordinary nonlinear programs. Since the stability constraint is described generally by eigenvalues or norm of Jacobian matrices of systems, this results in the semismooth property of NPSC problems. The optimal conditions of both NPSC and its smoothing problem are studied. A smoothing SQP algorithm is proposed for solving such optimization problem. The global convergence of algorithm is established. A numerical example from optimal power flow (OPF) is done. The computational results show efficiency of the new model and algorithm. © The Author(s) 2010.published_or_final_versionSpringer Open Choice, 21 Feb 201

Voltage collapse mechanism based on system circuit and its solution manifolds

The problem of voltage collapse in the power system occurs when the load parameter exceeds some critical value. The critical operation point is known as the nose point in P-V curve. In this paper, the mechanism of voltage collapse is explained based on system circuit and solution manifolds. The corresponding mathematical model is derived. The proven theorem shows that the essential reason for voltage collapse is that the solution manifold of injection branch equations being not transversal with that of linear network equations. And the coincidence of the non-transversal of solution manifolds with voltage collapse and static bifurcation is proved.published_or_final_versio