To address resource misallocation caused by siloed planning of power and transport systems under large-scale EV adoption

this study develops a coordinated planning framework that explicitly embeds charging-aware traveler equilibrium. A tri-level architecture is proposed— power expansion

road expansion

and route-charging user equilibrium—where the upper and middle levels determine infrastructure investments and the lower-level captures joint path-charging choices via a variational inequality (VI). The tri-level model is equivalently recast as a bilevel mathematical program with VI constraints (MP-VI)

and an MP-VI-driven fixed-point decomposition algorithm is designed for solution. A case study on Wuhan’s coupled power and transport networks shows robust convergence and favorable scalability. The proposed model co-optimizes investment in charging facilities

transmission upgrades

distributed generation

and road capacity

yielding substantial gains in system-wide economic efficiency and operational performance. The framework provides a generalizable paradigm for coordinated planning of future power-transport integrated systems.