With the development of smart grid and new elecLTicity reform，the uncertainty of new energy and power market ti·ading will affect the power supply capacity of distribution network. To evaluate and improve the power supply capacity

we first establishes a robust optimal dispatching model considering the unce1tainty of the new energy. Secondly

in order to explore the impact of power market ti·ansactions

the improved repeated power flow method is used to calculate the maximum power supply capacity (TSC) and mru·ket revenue of the distribution network under different power transaction scenarios. Finally

for scenarios where the TSC does not meet the standard

the improved PSO optimization algorithm is used to re-dispatch and improve TSC. The correlationsbetween TSC and market profit are determined through case studies: a trade-off relationship. Under the premise of ensuring safety

market revenue is reduced

and dispatching results are optimized to improve the TSC. The optimal 如patching model considering economy and safety of distribution network under power market was proposed to provide guidance for distribution network planning and optimized operation.