The operation of new distribution networks incorporating large-scale photovoltaic systems and flexible loads are becoming increasingly complex. The optimal configuration of synchrophasor measurement unit for distribution network (D-PMUs) can provide effective synchronized measurement data for coordinated scheduling and control. However

when the distribution network experiences an N-1 contingency and undergoes reconfiguration

the original configuration scheme may fail to meet the requirements of scheduling and control. Therefore

an D-PMU configuration optimization method considering N-1 contingency reconfiguration is proposed. This method introduces a node vulnerability index that accounts for node voltage loss and network topology. To ensure the observability of the distribution network after fault reconfiguration

an D-PMU configuration optimization model considering N-1 contingency reconfiguration is proposed. The network topology is acquired through distribution network reconfiguration. Observability constraints under N-1 fault conditions are established

taking into account the impact of limited D-PMU channels. The model also incorporates measurement information from supervisory control and data acquisition (SCADA) systems and advanced measurement infrastructure (AMI). Furthermore

a unified D-PMU configuration optimization model is established with comprehensive consideration of economic efficiency

full-network observability under normal conditions

zero-injection nodes

observability under N-1 contingency reconfiguration

D-PMU channel limitations

and existing traditional measurements. The feasibility and effectiveness of the proposed method are verified by using the IEEE 33-node and IEEE 69-node test systems.