Research On Preventive Reconfiguration Strategy Of Distribution Network Based On Reliability Of High Sensitive Load Power Supply

The distribution network is the ground bridge connecting the transmission network and the users.The evaluation of power supply reliability of sensitive load is an important basis for the distribution network to maintain reliable operation of high sensitive load in the face of higher power supply requirements.The optimal reconstruction of distribution network is an effective method to ensure that the distribution network chooses the best operating state under various indexes.With the rapid development of social economy and the acceleration of sensitive load growth,new energy output is unstable.In the near future,the access of a high proportion of new energy will reduce the power quality of the distribution network,thus reducing the operation efficiency of sensitive load and even causing equipment operation failure.In this context,when the voltage drops to the uncertain region of the voltage tolerance curve of the sensitive load,load loss may occur,which should be paid attention to in the distribution network planning to improve the safety and economy of the network.Therefore,the research on the preventive reconstruction strategy of distribution network based on the supply reliability of high sensitive load has important theoretical and practical significance.Based on various types of SARFI indicators,this paper analyzes the risk characteristics of the impact of voltage sag events on electrical equipment or areas.Then take the process of the fault shutdown of the variable frequency speed regulation motor when the voltage drop occurs as an example,analyze its voltage sensitivity and estimate the failure probability of the variable frequency regulator in the voltage tolerance uncertainty area.The loss of voltage-sensitive load is included in the objective function of distribution network reconstruction.Secondly,the characteristics of short-term changes in the distribution network such as intermittent distributed power sources,electric vehicle charging loads,and other general power loads are explored.Therefore,the law of short-term changes in the distribution network is introduced to lay the foundation for preventive restructuring.When the classical theory method is used to analyze the reliability of a new distribution network that contains highly sensitive loads,many limitations will inevitably appear.Aiming at the problem that the existing algorithm ignores the sensitive load in the distribution network,this paper proposes an improved distribution network reconstruction genetic algorithm(GA)method.A coding method of ring network positioning switch suitable for the characteristics of distribution network is adopted.Compared with the traditional binary method,the efficiency of the search solution will be greatly improved.A unique objective function is set for highly sensitive loads.The objective function fully combines the distribution points of sensitive loads in the distribution network and the tolerance characteristics of various sensitive loads.It has a strong effect on the distribution network containing highly sensitive loads.Targeted.In the power flow calculation of the distribution network,dynamic parameter variables are selected to simulate the changing rules of various power loads with time,so that the distribution network reconstruction becomes a dynamic evolution process,and the corresponding optimal state of the distribution network becomes a Dynamic solution of changes in distribution network.Finally,combining the methods and ideas of the above chapters,the IEE33 node is used as an example to simulate the impact of short-term load changes in the regional distribution network on the reliability of highly sensitive load power supply,and to implement preventive reconstruction of the distribution network through improved GA processing.Case simulation analysis shows that the proposed improved GA algorithm can effectively realize the reconstruction of distribution network with highly sensitive load.When the distribution network fluctuates,the voltage of the sensitive load node is dynamically stabilized within the minimum voltage drop,thereby ensuring the reliability of the power supply of the sensitive load.