Abstract: An optimization method was proposed to layout electric vehicle charging facilities considering

power quality constraints. A comprehensive power quality index model considering the average value of nodal

three-phase unbalance degree and the maximum value of nodal voltage deviation was established. Meanwhile，the

mathematical model considering the first and second static voltage stability indexes was established. Then，the

comprehensive power quality index，network loss index and static voltage stability index were taken as the

optimization objectives，the improved multi-objective cuckoo search algorithm was utilized to solve the proposed

model. The IEEE 33 bus distribution system was taken as an example，and the distribution optimization scheme of

charging facilities was given. The simulation results show that the nodal three-phase unbalance is significantly

reduced after the charging facilities were connected，and the voltage deviation keep within the allowable range. At

the same time，the influence of different optimization objectives and optimization methods were compared to verify the effectiveness，rationality and superiority of the proposed optimization method.

      Key words: distribution network；power quality；charging facilities；placement optimization；multi-objective

cuckoo search algorithm（MOCS）