Dynamic Risk Assessment Of Operational Profits And Losses And Iterative Bidding Mechanism Of Power Generators

In the power market environment,the fluctuation of load and electricity price,the random output of renewable power supply,the change of network topology,and the adjustment of the system operation mode have increased the risk for the operating income of generation companies(GENCO).In order to help GENCO accurately assess their risks and formulate appropriate bidding strategies and generating unit plans,this dissertation presents a pair-copula based VaR evaluation model for the profit and loss risk of GENCO.First,based on the AC power flow,the optimal dynamic economic dispatch model of power grid is established to calculate the locational marginal price(LMP).Then,the pair-copula theory is introduced to construct the high dimensional vine-Copula dependent structure of the loss functions of GENCO.Finally,the value at risk(VaR)of portfolio under different confidence levels is calculated based on its definition.The example of IEEE39-bus system is taken to verify the effectiveness of the proposed model and method.As one of the core issues of power market-oriented reform,iterative bidding mechanism can promote generators to quote electricity price rationally and organize production.It can also give buyers the ability to negotiate,and promote the coordinated and efficient operation of the electricity market.However,current iterative bidding methods mainly settle accounts according to the quoted price or the uniform marginal clearing price.Neither of these two bidding methods has incentive compatibility characteristics which can promote the generation company to quote at real cost,and the generation company tends to quote higher price.Moreover,most of the existing mechanisms have too many iterations to be applied.Therefore,an iterative bidding model for power generation market based on target cascade analysis theory is proposed.Power generators and independent system operators are regarded as different stakeholders,and their objectives are optimizing the production efficiency and minimizing the cost of purchasing electricity respectively.Prallel solution of the two objectives are realized by connecting of power generation.Considering the influence of network constraints,the model can effectively motivate generators to report their real costs and is conducive to the optimal allocation of social resources.Examples of IEEE39-bus system and IEEE118-bus system show that target cascade analysis can be applied to the iterative bidding mechanism of fully competitive power generation market,and the convergence and computational efficiency can meet the requirements.