| Along with the advancement of the new power market reform,the annual planned power of China's power system is gradually being replaced by medium and long-term trading electricity power.Unpredictable factors will lead to unexpected operation modes of the power grid,such as the uncertain market behavior of electricity market participants,the imbalance of the power generation,and the uncertainty of transaction results in medium and long term trading,resulting in uneven power flow distribution and grid safety margin.The decline has increased the complexity of the system operation mode arrangement,which may cause serious power system security issues.Therefore,relevant research on power trading behavior modeling and simulation analysis and trading transaction security check models in the middle and long-term trading process of power market are carried out.The main works are as follows.With a hybrid simulation method combining computer agent model and experimental economics,the development of power market trading simulation applications based on the Dynamic Simulation Platform for Macro-Energy Systems is combined with statistical analysis,causal analysis,and behavior analysis to analyze the long-term trading behavior of power producers.It's the first step to explore the key driving factors of the power producers' trading behavior by combining expert knowledge,prior knowledge and related literature.Then in order to establish a trading agent model with the same distribution characteristics as the real participants' trading behaviors,Bayesian Network Model is adopted based on the key driving factors,and the validity of the model is verified.According to the characteristics of decentralized power transactions in the market environment,a medium-long term power security check mechanism based on market members' willingness to declare transactions is designed in the hybrid simulation environment,including two-step verification mechanism that are pre-calculation of limit power and post-safety check and correction.To meet the practical demand of pretransaction safety check for medium and long-term transactions,this thesis proposes a solution model of limit power considering actual operating conditions of power grid.The model is based on security constrained unit commitment,and comprehensively takes many constraints into consideration such as power system balance constraints,unit operating constraints,power grid safety constraints,and the sensitivity coupling constraints of each unit in the unit group to the transmission section.The theoretical and simulation calculations show that the method considers the coupling of security constraints and sensitivity of the system well,which lays a foundation for guiding the benign operation of medium and long-term power trading.In the post-transaction check and correction mechanism,this thesis constructs a SCUC optimization model of daily power safety check and safety correction based on a contract decomposition optimization model.Annual or monthly multi-component contracts in the electricity market in the hybrid simulation environment are decomposed into daily electric quantity,which is regarded as a strict constraint.In addition,the feasibility evaluation of electric quantity contract execution is obtained under system security constraints and boundary condition constraints and unit on-off characteristic constraint.A safety correction model is proposed to provide a power contract correction method for line congestion.The IEEE-118 system and an actual model of a provincial network are utilized to conduct simulation tests.The results show the follows.The proposed model can effectively quantify the enforceability of the power contract and evaluate the cross-border risks brought by the power contract to the power system.And it also can puts forward amendments that take into account system safety constraints and unit start-stop characteristics for the unreasonable power contract,and finally reaches the minimum adjustment of power to eliminate the congestions. |
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