Distribution networks with high penetration of Distributed Energy Resources (DERs) increasingly rely on communication networks to coordinate grid-interactive control. While many distributed control schemes have been proposed, they are often evaluated under idealized communication assumptions, making it difficult to assess their performance under realistic network conditions. This work presents an implementation-driven evaluation of a representative virtual power plant (VPP) dispatch algorithm using a co-simulation framework that couples a linearized distribution-system model with packet-level downlink emulation in ns-3. The study considers a modified IEEE~37-node feeder with high photovoltaic penetration and a primal--dual VPP dispatch that simultaneously targets feeder-head active power tracking and voltage regulation. Communication effects are introduced only on the downlink path carrying dual-variable updates, where per-DER packet delays and a hold-last-value strategy are modeled. Results show that, under ideal communication, the dispatch achieves close tracking of the feeder-head power reference while maintaining voltages within the prescribed limits at selected buses. When realistic downlink delay is introduced, the same controller exhibits large oscillations in feeder-head power and more frequent voltage limit violations. These findings highlight that distributed DER control performance can be strongly influenced by communication behavior and motivate evaluation frameworks that explicitly incorporate network dynamics into the assessment of grid-interactive control schemes.

翻译：高渗透率分布式能源资源（DERs）的配电网络日益依赖通信网络来协调电网交互控制。尽管已有多种分布式控制方案被提出，但它们通常在理想化通信假设下进行评估，难以在实际网络条件下衡量其性能。本研究采用实现驱动的评估方法，通过一种联合仿真框架对代表性虚拟电厂（VPP）调度算法进行评价，该框架将线性化配电系统模型与ns-3中的数据包级下行链路仿真相结合。研究采用改进的IEEE~37节点馈线模型，该模型具有高光伏渗透率特性，并应用原始-对偶VPP调度方案，同时实现馈线首端有功功率跟踪与电压调节。通信效应仅影响承载对偶变量更新的下行链路路径，其中建模了每个DER的数据包延迟以及保持最后值策略。结果表明：在理想通信条件下，该调度方案能紧密跟踪馈线首端功率参考值，同时将选定母线的电压维持在规定限值内；当引入实际下行链路延迟后，同一控制器在馈线首端功率上出现大幅振荡，且电压越限频率显著增加。这些发现凸显分布式DER控制性能可能受到通信行为的强烈影响，并推动了在电网交互控制方案评估中显式纳入网络动态特性的评估框架发展。