Reliability Analysis Of Distribution Network Considering The Impact Of Microgrid Market Transaction

With the deregulation of the electricity market has been accepted and adopted by many countries and the decrease in the cost of distributed generation,the decentralized users have their own distributed generation.The trend of microgrid operation is that the ownership of distributed generation belongs to a decentralized self-interest user and the network operation right belongs to the third-party company.Under the market environment,the profit-seeking market behavior of the market participants affects the power characteristics of the power supply and load in the microgrid.And the power characteristics affect the reliability of power equipment and distribution network.This paper focuses on the related problems in the process of distribution reliability evaluation and proposes a reliability analysis model considering the impact of microgrid market transactions.The specific work is summarized as follows.Firstly,the development trend of microgrid operation and the business between microgrid and others are analyzed.Then the influence mechanism of microgrid market transaction on reliability is expounded.The dispatching of distributed generation in the market environment is the basis of reliability analysis in this paper.Based on the existing market framework of microgrid based on a multi-agent system,the economic scheduling model of microgrid operators under the market environment is built.In this model,the bidding strategy of each market participant is determined by the cost function and the strategy coefficient,and the PAB model is adopted for clearing.Secondly,considering the randomness of the power supply,load,bidding curve and the price of the external power grid,the probability model of each uncertain factor is established.In this paper,the existing scenario analysis method is improved and the time-sequential correlation of data is taken into account.Firstly,the daily wind power output/load demand/electricity price/ bidding curve is taken as a scenario unit,then a joint time-sequential scenario set is built by the Latin hypercube sampling and the backward scenario reduction method,which not only takes into account the data variation characteristics of a single factor but also preserves the correlation between multiple factor data.Finally,a comprehensive failure probability model of components considering load rate is established,and the system state scenario is generated by combining power-load-market joint time-sequential scenario,economic scheduling model and component failure probability model.Finally,a reliability evaluation method of distribution network including microgrid is proposed to evaluate the system state scenario,and the final reliability index is calculated by scenario probability weighting.The improved RBTS BUS6 system is used for simulation analysis.The results show that the reliability analysis method based on the power-load-market joint time-sequential scenario proposed in this paper can ensure the calculation accuracy and improve the calculation efficiency.According to the reliability results,reasonable allocation of reserve capacity according to the output level of different generations can effectively improve the reliability of power supply.The load transfer with appropriate load characteristics can reduce the failure probability of components in the peak load period.Meanwhile,the reserve capacity of the system is increased equivalently.So the reliability of the distribution network can be improved.Otherwise,it will make the reliability of the peak load period worse.Besides,the market will choose the market participants with a lower bidding price.The lower the bidding price of the entity with poor reliability or the higher the bidding price of the entity with better reliability,the more the output proportion of the entity with low reliability is,the more the risk of the EENS of the system will increase.It is necessary to consider the configuration of reserve to reduce this risk...