Two-Layer Optimal Configuration Of Microgrid By Risk Quantification Under Renewable Energy And Load Uncertainty

Seeking a feasible way to replace non-clean energy with clean energy has become an inevitable trend in the context of global green and low-carbon transformation.As a small-scale power generation and distribution system,microgrid can effectively utilize renewable energy such as wind energy and solar energy,solve the problems caused by large-scale renewable energy directly entering the grid,and improve the utilization rate of renewable energy.There are many uncertainties in the planning and dispatching operation stage of microgrid,mainly including the uncertainty of renewable energy and load demand.One of the key factors affecting the planning and operation scheduling of microgrids is whether this uncertain information can be reasonably recognized and accurately classified.There are uncertainties on both the power generation side and the load demand side.In order to cope with these uncertainties,a certain backup capacity needs to be set up to ensure the safe and reliable operation of the microgrid.The size of the backup capacity should not only meet the requirements of the microgrid for power supply reliability,but also take into account a certain economy.The optimal configuration of the microgrid should consider the benefits of the whole life cycle of the system,including the capacity configuration cost and dispatching operation cost of the system,so as to evaluate the advantages and disadvantages of the optimal configuration results.Therefore,the optimal configuration and operation of the microgrid are coupled,and the optimal configuration model should also take into account the operation optimization of the system.According to the above analysis,this paper proposes a two-layer optimal configuration model for microgrid risk quantification under source and load uncertainty.The specific work content of this paper is introduced in detail.Firstly,this paper uses the method of scenario analysis to describe the uncertainty of renewable energy and load demand in the microgrid.The probability distribution is obtained by fitting the real historical data of wind speed,light and load demand in Inner Mongolia.Generate scenes using Monte Carlo sampling.A large number of generated initial scenes are reduced using backward scene reduction to obtain typical scenes.Secondly,this paper introduces the concept of risk quantification,taking into account the reliability and economy of the system backup capacity setting.Considering the cost of system backup capacity setting and the probability of insufficient backup capacity and its possible losses.Quantify the consequences and losses caused by insufficient system backup.Use risk value to measure the rationality of system backup capacity setting.The microgrid can not only meet the requirements of system power supply reliability,but also take into account the economy of system backup.Thirdly,in this paper,a two-layer optimal configuration model of microgrid is established.The upper layer is a capacity-optimized configuration model,which is used to determine the optimal capacity of each distributed power source in the system.The lower layer is the optimal scheduling model,which is used to calculate the operating cost of the microgrid under the given configuration capacity of the upper layer according to the established operation strategy.Two-layer optimization model takes into account both system configuration optimization and operation optimization.The optimization results of the upper and lower layers influence each other to seek the optimal configuration result of the microgrid.Finally,the two-layer optimal configuration model is established in MATLAB.The genetic algorithm is used to solve the upper-level capacity optimization problem.The CPLEX solver is used to solve the lower-level operational optimization problem.The simulation results show that the method proposed in this paper can effectively obtain the optimal configuration results of the microgrid.The risk quantification model can take into account the reliability and economy of system backup,and provide a reference for microgrid configuration and backup capacity configuration.