城市交通网络因交通拥堵面临严峻挑战，进而引发不利的环境与社会经济影响。车辆准入控制（Vehicular Admission Control, VAC）策略作为一种有前景的缓堵手段应运而生。该策略依托信息与通信技术，通过调控车辆进入网络的时机与方式，在时空维度上优化各类交通性能指标。尽管VAC策略已取得显著进展，但其在存在建模不确定性条件下的稳定性问题仍缺乏深入研究。本文考察一类分布式VAC方案在建模不确定性下的稳定性特性。具体而言，我们考虑具有非线性动力学特征、且宏观基本图（macroscopic fundamental diagram, MFD）呈凹性的大规模异构城市交通网络，并假设流量、密度与速度之间的关系存在有界不确定性。在此框架下，我们分析一类由一般非线性形式描述的分布式VAC动力学。基于无源性理论（passivity theory），我们推导出关于VAC方案设计的可扩展、局部可验证条件，从而在建模不确定性存在时提供稳定性保障。文中给出多个示例以说明所提设计框架的适用性。数值仿真分别在6区域与20区域系统上开展，验证了所提分析结果的有效性与实际相关性。

Urban transportation networks face significant challenges due to traffic congestion, leading to adverse environmental and socioeconomic impacts. Vehicular admission control (VAC) strategies have emerged as a promising solution to alleviate congestion. By leveraging information and communication technologies, VAC strategies regulate vehicle entry into the network to optimize different traffic metrics of interest over space and time. Despite the significant development of VAC strategies, their stability at the presence of modelling uncertainty remains under-explored. This paper investigates the stability properties of a class of decentralized VAC schemes under modelling uncertainty. Specifically, we consider large-scale, heterogeneous urban traffic networks characterised by nonlinear dynamics and concave macroscopic fundamental diagrams with bounded uncertainty between flow, density, and speed. In this context, we examine a broad class of decentralized VAC dynamics, described by general nonlinear forms. Using passivity theory, we derive scalable, locally verifiable conditions on the design of VAC schemes, that enable stability guarantees in the presence of modelling uncertainty. Several examples are presented to illustrate the applicability of the proposed design framework. Our analytical results are validated through numerical simulations on a 6 and a 20-region system, demonstrating their effectiveness and practical relevance.