Research On Reconfiguration And Automation Planning For Distribution Network

With the rapid and sustained development of economy,the demand for electrical energy is increasing,and customers also have increasingly strict requirements for power supply reliability.The widely used distribution generation(DG)and energy storage system(ESS)enable a distribution system to have a more flexible fault reconfiguration capability.Distribution automation(DA)is an important means to improve the quality and reliability of power supply and achieve economical and efficient operation of the distribution network.This paper focuses on the reconfiguration and automation planning for distribution network,the main work and achievements are as follows.1)In order to enhance the service reliability and the benefit of distribution networks with DGs and ESSs,this paper proposes a novel distribution system reconfiguration(DSR)model including DGs and ESSs.Meanwhile,the impact of sectionalizing switches(SSs)and tie switches on reliability is considered.The concept of “boundary switch” is introduced for quantifying the customer interruption duration.The DSR model is presented to minimize the sum of the customer interruption cost,the depreciation cost of DGs and ESSs,and the operation cost of switches.Furthermore,the proposed model is converted into a mixed-integer linear programming,which can be efficiently solved by commercial solvers.Finally,the validity and efficiency of the proposed DSR model are verified by a modified IEEE 33-bus system and a modified PG&E69-bus network.2)The economy and reliability are two important indicators for considering the optimal placement of sectionalizing switches,but the two are often relatively contradictory.This paper proposes an SS allocation model that comprehensively considers economy and reliability.The genetic algorithm is used as the basic framework,and the SS configuration solution is encoded on the chromosome in integer form.Then the distribution system reconfiguration strategy mentioned in Chapter 2 is used for the N-1 safety verification.The SS placement model is presented to minimize the sum of the investment cost of SS and the system power loss cost.Finally,the validity and efficiency of the proposed SS placement model are verified by a modified IEEE 33-bus system.3)Fault indicators(FIs)and SSs are of great importance in distribution automation for reliability enhancement and efficiency improvement.This paper intends to develop a model for the optimal simultaneous allocation of FIs and SSs in the distribution network based on reliability and cost-benefit analyses.Three position matrices are obtained by preprocessing the topology of distribution networks to enable the establishment of the proposed model.Furthermore,a quantification method for the customer interruption duration under different contingencies is constructed to achieve a more precise and practical reliability evaluation.The resultant optimization problem is formulated as a mixed-integer linear programming that can be efficiently solved by commercial solvers.A modified IEEE 33-bus network and a real urban distribution system are used to verify the effectiveness and efficiency of this model.