To address the efficiency limitations of vehicle-unmanned aerial vehicle (UAV) collaborative operations in large-scale and high-frequency inspections of VSC-HVDC transmission lines, this paper proposes a path-energy coordinated bi-level nested optimization framework to address the strong coupling among vehicle route planning, UAV task scheduling, and battery resource allocation. First, a unified multi-objective constrained optimization model is established, in which vehicle parking decisions, UAV operational range, and path-dependent energy consumption are incorporated into a single decision-making framework, thereby enabling coordinated modeling of route planning and energy allocation. Second, a bi-level optimization structure with collaborative evolution between outer-layer route optimization and inner-layer energy scheduling is constructed. The execution results of the inner-layer tasks are fed back to refine the outer-layer path search and resource allocation, thereby achieving coordinated optimization among vehicle routing, UAV task assignment, and battery scheduling. Finally, simulation studies are conducted based on a typical VSC-HVDC transmission line inspection scenario. The results show that the proposed method achieves major convergence within 15-25 iterations, reduces the total operation time to 182 min, and attains a battery utilization rate of 92.3%. Compared with existing collaborative optimization methods, the proposed method reduces the total operation time by 13.2%~25.3% and maintains good scalability and engineering applicability under expanded inspection scales and varying UAV endurance conditions.