Research On Optimal Operation Of Renewable Energy Power System Considering The Operation Flexibility Of Concentrating Solar Power Plant

The dual pressure of global fossil fuel crisis and environmental pollution has promoted the clean transformation of power system in various countries,which has promoted the rapid development of renewable energy generation represented by wind power and photovoltaic,the large amount of access will bring new problems to the flexible operation of the power system.As an emerging renewable generation technology,concentrating solar power(CSP)has the similar inertia and schedulability to conventional power plants.The flexible operation of CSP has significant advantages in promoting the accommodation of renewable energy and participating in grid auxiliary services.In view of the problems of scarcity of flexible resources and the difficulty of local accommodation of electricity in northwest renewable energy rich areas in the low-carbon transformation process of China,this paper carried out research on the optimal operation of renewable energy power system considering the operation flexibility of the CSP plant.The operation modes,operation scenarios and energy flow exchange model of the CSP plant were studied.Firstly,introduced the structure and components of the CSP plant.On the basis,the working principle of the CSP was elaborated in detail,and combined with the internal energy cycle process,summed up five different operation modes of the CSP plant.Then,considering meteorological conditions,thermal energy storage state and actual operation requirements,the operation scenarios of the CSP plant are divided in detail.Then,according to the energy transfer process,the energy flow exchange model of the CSP plant was further ed.Day-ahead and intra-day dispatching model of CSP providing energy and reserve capacity for the power system were studied.Focus on the problems that the scarcity of flexibility and insufficient of spinning reserve capacity in high renewable energy penetrated system,the operation scenario of CSP providing reserve capacity for the system was studied.Considering the constraints of thermal energy storage capacity,modeled the operation of CSP providing reserve capacity.From the perspective of system economics,with the goal of reducing units operating cost and load shedding cost,day-ahead and intra-day dispatching model of CSP providing energy and reserve capacity were established,that each unit start-stop operation,energy efforts and reserve capacity allocation plan can be solved.Case results showed that the model can improve the economical property of the system and reduce the occurrence of load shedding,which is conductive to strengthen the reliability of power system.The cooperative optimization operation model of high renewable energy penetrated system with CSP plants sending electricity to receiving system via HVDC tie-line was studied.Considering the characteristics of China’s resource distribution,the operation scenario of the high renewable energy penetrated system with CSP plants sending electricity to receiving system via HVDC tie-line was taken as the research object.Considering system overall efficiency,aiming at minimizing the cost of system operation,peak shaving and power curtailment,also considering the flexible adjustment of CSP and DC tie-line,the power of DC tie-line was also taken as an optimization variable to participate in the system diapatching,established the collaborative optimization operation model.Based on the power grid planning data of one northwest province in China,from the point of system economy,peak shaving parameters and green electricity index,the benefits of accessing CSP were analyzed.The results showed that the access of CSP could reduce the operating cost of the system,improve peak conditions of thermal power units,reduce the emission of atmospheric pollutants,promote the accommodation of renewable energy and achieve a higher proportion of electricity from clean energy,which is conducive to the low-carbon development of the power system.