Research On Fault Self-healing Method For Distribution Network Based On Smart Algorithms

With the rapid development of economic,the demand for electric power is rising quickly,higher requirements for the power grid is putting forward.How to achieve the goal of uninterrupted power supply and quickly fault locate,isolate,and self-healing has become a daunting challenge the power system facing with.The distribution network as a system directly connected with users will inevitably have a huge impact on people's life and production.As its core function,fault self-healing feature can effectively reduce the incidence of large-scale blackouts and improve the reliability of power supply of the distribution network,provides an important guarantee to distribution network of efficient,safe and stable operation.However,due to the level of distribution automation and the equipment in various distribution areas in our country is uneven;the grid structure of distribution network is relatively weak;the reliability of power supply is poor;the problem impacting on the grid caused by the large number of renewable energy and distributed generation access to grid can not effectively solve;the lack of interaction between distribution systems and users and other issues,the development of smart distribution network is still in the exploratory stage.Therefore,accelerating the construction and development of smart distribution network to solve a large number of grid-connected distributed generation problems and carry out research on fault self-healing of smart distribution network is imminent.Cyber-Physical System(CPS)is a new type of embedded system that integrates computing,communication and control together.It can sense the dynamic changes of external environment in real time,then control and modify the physical environment according to the established goals.The fault self-healing processes of smart distribution network is dependent on the real-time monitoring of the physical environment,timely detect any fault,and quickly take a appropriate method to recovery the fault.Therefore,its proposal and development are conducive to the organic combination of primary power system and power information system,providing a new idea and method for achieving the requirements of smart distribution network.Therefore,based on the characteristics and requirements of smart distribution network,this paper proposes to introduce the idea of cyber-physical system into the whole processes of fault self-healing in smart distribution system considering the impact of numbers of distribution generation access to the distribution network.First,a hybrid time petri net method is used to establish the main electrical components model used in the physical end of smart distribution network during the fault self-healing process,and then the CPS architecture of smart distribution network is constructed.Secondly,according to the two operation modes of DG,the mathematical model of fault self-healing of smart distribution network with node voltage deviation as the objective function and the DG islanding model with load and weight weighted sum of its importance as the objective function are respectively proposed.Then,combining the binary quantum particle swarm algorithm with the binary fruit fly optimization algorithm,a binary hybrid algorithm is proposed to recovery faults of smart distribution network with distributed generation.Finally,an example is given to verify the binary hybrid algorithm,the result indicates it has better convergence performance and global optimization ability.