EVRPTW Benchmark Dataset with Heterogeneous Charging Stations and Two Time-Window Variants

This record provides an EVRPTW benchmark dataset built on the Homberger 1000-customer VRPTW instances (60 problems from six families: R1, R2, C1, C2, RC1, RC2). For each base instance, two variants are provided: (A) original customer time windows with charging stations appended in standard VRPTW text format, and (B) the same augmented network with distance-based relaxation of customer due dates, limited by the depot closing time. Charging stations are sampled within the customer coordinate bounds with a minimum separation between stations. A normalized local density score is used to define heterogeneous station attributes: charging rate is assigned deterministically from that score, while price and waiting time are given through station-specific log-normal parameters (price_mu, price_sigma, wait_mu, wait_sigma). The package includes augmented .txt instance files, matching *_stations.csv station tables, params.json (generation settings and random seed), ev_specs.json (reference battery capacity Q and consumption rate h), README.md, the original unmodified Homberger files, and a code/ folder with the scripts used to generate the benchmark and run the bundled checks and analyses. It also includes the complete sensitivity-analysis outputs used in the paper. All charging-station data, variant B relaxations, and author code were produced by the authors of this dataset. The original Homberger instances are included unchanged.本数据集为基于Homberger提出的1000客户VRPTW（Vehicle Routing Problem with Time Windows，带时间窗车辆路径问题）实例构建的EVRPTW（Electric Vehicle Routing Problem with Time Windows，带时间窗电动车辆路径问题）基准数据集，涵盖6个类别共计60个问题（R1、R2、C1、C2、RC1、RC2）。针对每个基础实例，本数据集提供两种变体：（A）采用标准VRPTW文本格式，保留原始客户时间窗并追加充电站的实例；（B）基于同一扩展网络，以距离为基准松弛客户交货期，且松弛后的时间不超过仓库关闭时间的实例。充电站将在客户坐标范围内采样生成，且各充电站之间保持最小间距。采用归一化局部密度评分定义异构充电站的属性：充电速率由该评分确定性分配，而充电站的价格与等待时间则通过专属对数正态分布参数（price_mu、price_sigma、wait_mu、wait_sigma）生成。本数据包包含以下内容：扩展格式的.txt实例文件、与之配套的*_stations.csv充电站表、params.json（生成配置与随机种子）、ev_specs.json（参考电池容量Q与能耗率h）、README.md、原始未修改的Homberger源文件，以及包含基准数据集生成、配套检查与分析脚本的code/文件夹。此外还包含论文中所用的全部敏感性分析输出结果。本数据集的所有充电站数据、变体B的松弛规则与作者自研代码均由本数据集的作者完成编制。原始Homberger实例未做任何修改，直接保留。