Abstract Due to exponential growth of large-scale PV plants, automatic approaches for PV system protection are gaining prodigious importance. Even with the use of standard protection devices, faults in PV arrays may remain undetected. To address such an important issue, this paper focuses on string level monitoring to develop the functionality of automatic fault detection, location and fault type identification. The fault detection is achieved through the generation of fault indicator signals called residuals and comparison with a pre-set threshold. The automatic identification of fault type is achieved by the development of a procedure reliant on the variations in the string current profiles relative to the type of fault. Finally, the location of faults is estimated through the combination of analytical and regression expressions reliant on fault type, irradiance levels and string current measurements. Various line-line fault cases are tested and verified using the proposed method through simulations and experiments. The proposed method is experimentally evaluated for multiple fault scenarios on an experimental setup located within an existing solar farm to emulate conditions akin to real world solar farms.

中文翻译：

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一种太阳能光伏系统故障检测、识别和定位技术

摘要 由于大规模光伏电站的指数增长，光伏系统保护的自动化方法变得越来越重要。即使使用标准保护设备，光伏阵列中的故障也可能无法检测到。为了解决这样一个重要问题，本文重点关注串级监测，以开发自动故障检测、定位和故障类型识别的功能。故障检测是通过生成称为残差的故障指示信号并与预设阈值进行比较来实现的。故障类型的自动识别是通过开发依赖于与故障类型相关的串电流分布变化的程序来实现的。最后，故障的位置是通过依赖于故障类型、辐照度水平和串电流测量值的分析和回归表达式的组合来估计的。通过仿真和实验，使用所提出的方法测试和验证了各种线-线故障情况。所提出的方法在位于现有太阳能发电场内的实验装置上针对多个故障场景进行实验评估，以模拟类似于现实世界太阳能发电场的条件。