This work presents an experiment proposal for continuous partial discharge analysis during an automated thermal cycle experiment for hydro generator stator coils/bars. It is an innovative approach because we propose to perform partial discharges test and thermal cycle experiment simultaneously, while they are usually performed individually. We developed an automated test bench that allows performing data acquisition throughout the experiments. We decided to force different coil failures during the tests to observe any changes in the partial discharges trend. First, we changed the thermal cycle temperature limits, and this led to coil overheating before an electrical failure occurred in the insulation. Later, we applied a voltage that was higher than the rated for the coil, which led to a faster electrical failure. The partial discharges trend changed moments before the electrical fault, and the system was able to identify such change. Our preliminary results show that the continuous analysis of partial discharges trends might lead to better maintenance planning by identifying the moment when the hydro generator aging gets critical.

中文翻译：

---

自动热循环老化实验中的连续局部放电分析

这项工作提出了在水力发电机定子线圈/棒的自动热循环实验中进行连续局部放电分析的实验建议。这是一种创新方法，因为我们建议同时进行局部放电测试和热循环实验，而它们通常是单独进行的。我们开发了一个自动化测试平台，允许在整个实验过程中执行数据采集。我们决定在测试期间强制不同的线圈失效，以观察局部放电趋势的任何变化。首先，我们更改了热循环温度限制，这导致线圈在绝缘发生电气故障之前过热。后来，我们施加了高于线圈额定电压的电压，这导致了更快的电气故障。局部放电趋势在电气故障发生之前发生了变化，系统能够识别这种变化。我们的初步结果表明，通过确定水力发电机老化变得关键的时刻，对局部放电趋势的持续分析可能会导致更好的维护计划。