| As an important component of the power system,the distribution network is responsible for distributing electricity to users.As an important indicator to measure the capacity of distribution network,total supply capability effectively integrates the transfer capacity and supply capacity of the network,which can visually reflect the load supply capacity of the network and effectively measure the coordination between the level of power grid planning and the load.In the context of the current demand for refined planning,the application of total supply capability in distribution network planning is of great significance to improve system equipment utilization and save construction investment while meeting the safety and reliability of the network.Therefore,this paper focuses on the distribution network planning method based on the total supply capability.Firstly,a evaluation model of total supply capability of distribution network considering reliability and economic constraints is proposed.The method can be used to optimize the total supply capability with specific reliability indexes as constraints in some areas where the reliability requirement of distribution network is not high.It also combines the investment cost constraints to find the operation point with optimal economic efficiency with specific reliability requirements.Next,the connection mode of power supply units is analyzed based on the total supply capability.Evaluate the total supply capability at the unit level,and quantify the relationship between the total supply capability and distribution network feeder type,capacity,contact structure and other influencing factors under the reliability constraint index.Efficiency and economic benefit indexes are constructed based on the total supply capability to rank connection modes in a comprehensive manner.Summarizing and analyzing the characteristics of the high-efficiency connection modes.Recommendation for the selection of connection modes within the unit are proposed.Then,the matching relationship between main transformers and feeders in the power supply grid is analyzed based on the total supply capability.Hierarchical and zoned assessment of the total supply capability of the distribution network within a certain range.The influence of the disparity between the upper and lower level networks on the total supply capability is investigated.The matching relationship between substation capacity and network structure is explored.Combining differentiated reliability requirements to achieve the total supply capability partition optimization.Finally,a planning analysis based on the total supply capability of an actual distribution network is carried out.It is verified that using the total supply capability index reflecting the system load supply capacity to guide the distribution network planning can accurately calculate the safety margin of the network,obtain the operation point that takes both security and economy into account,excavate the power supply potential of the grid,and implement precise planning requirements. |
