Research On Optimization Planning Method Of Wind And Photovoltaic Power Generation Based On Power Supply Cost

Developing wind and photovoltaic(PV)power generation is an important measure to achieve the goal of carbon neutralization.With the rapid decline of wind and PV power generation equipment cost and the advent of power grid parity,China will continue to vigorously develop wind power generation.However,the output of wind and PV power generation is strongly uncertain.The load only can be supplied by wind and PV power supply with the cooperation of other flexible resources.Some peak output curtailment of wind and PV power generation in some periods has become a necessary measure to maintain the safe operation of the system.Reasonable curtailment measures can also be taken to improve the penetration rate of wind and PV power.However,the high curtailment ratio of wind and PV electricity will affect the power supply cost of the system.How to formulate a scientific optimal configuration scheme of wind and PV power considering the power supply cost of the system has become an urgent problem to be solved.The difficulty of the optimal optimization of wind and PV power generation lies in how to formulate the optimal wind and PV curtailment scheme for operation and determine the reasonable curtailment ratio for planning.In view of the above problems,the main work is as follows:(1)Aiming at the optimization planning of distributed renewable energy in distribution network,a distributed generation optimization planning method based on distribution network steady-state security region is proposed.Firstly,a maximum and minimum optimization planning model is established.The maximum consumption of renewable energy electricity and the lowest power supply cost are taken as the objective function.Secondly,the maximum optimization model is transformed into a linear programming model with the help of the security region linear expression in power injection space.The repeated network power flow calculation can be avoided.Finally,a case study of the IEEE 33-bus system is carried out.It is found that the penetration rate of renewable energy electricity can be effectively improved when suitable renewable electricity curtailment measure is taken.(2)Aiming at the optimization planning of renewable energy in wind-PV-thermal bundling system,a power supply optimization planning method based on the total social cost is proposed.Firstly,Composition of the total social cost and the calculation method of each sub item are given.Combined with the future development trend of the actual system,two wind power generation scenes are set up.Then,a bi-level power supply planning model based on the total social cost is established.The model solution process based on time-series simulation is formulated.Finally,under the above two scenes,the total social cost of developing high proportion of wind and PV power generation are evaluated respectively.It is found that there is a significant cost advantage when wind and PV electricity are generated with the “local development and consumption” mode in both scenes than “large-scale and long-distance transmission” mode.