| For a long time,due to the rapid economic development,there is a shortage of power and energy in many areas of China.There is a habitual thinking that resolving the load problem is more important than settling the risk of grid in the aspects of grid planning,investment,and construction.With the continuous improvement of power supply construction,the power supply shortage situation has gradually eased in recent years,but the risk of power grid operation still exists.Due to the increasing size of the power grid and the increasing load,the risk of power grid operation grows up clearly.Based on the statistics and analysis of the causes of large-scale blackouts at home and abroad,except for natural disasters,due to insufficient knowledge of grid operation risks during grid planning and design,electromagnetic loop within different voltage level exists in the process of grid upgrade.During grid regulation and control,the flow section control is unreasonable,and the load distribution is uneven.When a local accident occurs,according to the natural distribution characteristics of the transmission line impedance and the rapidity of power transmission,it is impossible to control the spread of the accident,and it is easy to produce a chain reaction,which will cause a series of collapse accidents and cause a large-scale paralysis of the power grid.Therefore,on the premise of strengthening equipment operation and maintenance,optimizing management models and other countermeasures,it is necessary to break through the habitual thinking that resolving the load problem is more important than settling the risk of grid.The optimization of the grid planning contributes to solving the risk problems of the grid,especially the risk under a special operation mode,which meets the requirements of safe,high-quality and economic operation of the power grid.Based on the current operation status of Liuzhou Power Grid,the risk points in the operation are comprehensively identified.The analysis shows that under certain major maintenance modes of operation,the risks of the power grid are not well controlled and there are many risks of collapse.To this end,BPA software is used to model Liuzhou Power Grid,N-1 static safety analysis is performed on specific maintenance operation modes,the impact and consequences of this risk are studied,and targeted solutions are proposed from the perspective of power grid planning.Furthermore,full consideration is given to the change of steady-state power flow under different operating modes during the year,and a typical day is selected to compare the power flow distribution before and after grid optimization,giving further analysis and demonstration of the feasibility of the planning scheme.At last,the best plan is chosen based on N-1 static safety and economic practicability.The research results show that the planning scheme proposed in this paper is practical and feasible,and can effectively resolve the grid risks under specific maintenance operation modes.In this paper,the power system analysis tool is reasonably used on the premise of fully considering the important role of power grid planning to resolve power grid risks,the system operation profession and the planning profession are combined to apply the actual operation results of the power grid directly to the power grid planning which can effectively solve the operation risks of the power grid,which makes the planning scheme closer to the practical application,and provides a reference method for power supply companies to solve the risks of the power grid.The practical significance of this paper is of great importance. |
