PowerSecure (PS), a subsidiary of Southern Company, operates over 1600 microgrids including a large fleet of standby diesel generators. Machines range from 125 to 2800 kW. There are two missions: standby power after utility failure and load management when utility is available. This report updates generator reliability data published over 20 years ago. These results are first derived from uniform records from a distributed data acquisition system. The unique aspects of this effort include automated data collection, analysis, and storage producing a standardized record for all machines and events. This greatly reduces the effort required to prepare reports and analysis. The automated collection largely eliminates human errors in data entry, and prevents post hoc adjustment of mission success or failure. We are not aware of previous published generator data using automated data acquisition. This study counts all failures and excludes none, whereas previous studies exclude more than half. This analysis expresses reliability as experienced by the customers. The number of machines, years in service, and years of operation greatly exceed the sum of previous published studies, enabling calculation of useful confidence limits. The fleet is heterogenous with machines from over a dozen manufacturers and many power ratings. Machine reliability was consistent across brands, and there is no significant difference in reliability for different size machines. This common assumption was not supported by the prior studies. High-quality data enables reliability growth management practices. The fleet reliability for outage demands of all durations increased from 95% in 2011 to 98% in 2014–18. Analysis of failures arrival time shows that the failure rate is strongly dependent on mission duration. The failure rates after 14 h are approximately 1% of the value for the first 30 min of operation. This has important implications for designing systems to meet specified reliability targets, and in interpreting and comparing results from fleets with different mission durations.

中文翻译：

---

大型柴油发电机组的可靠性评估

PowerSecure (PS) 是 Southern Company 的子公司，运营着 1600 多个微电网，其中包括大量备用柴油发电机组。机器范围从 125 到 2800 kW。有两个任务：市电故障后的备用电源和市电可用时的负载管理。本报告更新了 20 多年前发布的发电机可靠性数据。这些结果首先来自分布式数据采集系统的统一记录。这项工作的独特之处包括自动化数据收集、分析和存储，为所有机器和事件生成标准化记录。这大大减少了准备报告和分析所需的工作量。自动化收集在很大程度上消除了数据输入中的人为错误，并防止了任务成功或失败的事后调整。我们不知道以前发布的使用自动数据采集的发电机数据。这项研究计算了所有失败并排除了一个失败，而之前的研究排除了一半以上。该分析表达了客户体验的可靠性。机器的数量、服务年限和运行年限大大超过了以前发表的研究的总和，从而能够计算出有用的置信限。该车队拥有来自十多个制造商和许多额定功率的机器。不同品牌的机器可靠性是一致的，不同尺寸机器的可靠性没有显着差异。先前的研究不支持这一普遍假设。高质量数据支持可靠性增长管理实践。所有持续时间停电需求的车队可靠性从 2011 年的 95% 增加到 2014-18 年的 98%。故障到达时间分析表明，故障率强烈依赖于任务持续时间。14 小时后的故障率约为运行前 30 分钟值的 1%。这对于设计满足特定可靠性目标的系统以及解释和比较来自不同任务持续时间的舰队的结果具有重要意义。