The insulation material applied on the stator windings of automotive electric machines are susceptible to the excessive temperature rise. Typically, several thermocouples are embedded in the end-winding and the active winding in the slot to detect the peak temperatures in real-time to avoid thermal damage and adjust cooling. However, in the slot windings, the uneven distribution of power loss will change with frequency. This phenomenon causes the movement of the hotspot in the slot winding at different operating states, while it is not so obvious in the end-winding. As a result, the peak temperature in the slot winding cannot always be detected exactly by the fixed thermocouples, which has never been realized and valued. In this article, we analyze the movement of the hotspot in both of the slot winding and end-winding. In order to improve the detecting precision, we use an offline theoretical thermal-magnetic model to deduce the relationship between the temperatures at the measured position and real hotspot at various operating states. Then the thermocouple reading can be corrected in real-time according to the deduced relationship. The experimental test validates the performance of the proposed method in elevating the precision of peak temperature detection.

中文翻译：

---

高频汽车电机绕组峰值温度检测的校正


汽车电机定子绕组上使用的绝缘材料容易受到温升过高的影响。通常，在端部绕组和槽内的有源绕组中嵌入多个热电偶，以实时检测峰值温度，以避免热损坏并调整冷却。然而，在槽绕组中，功率损耗的不均匀分布会随着频率的变化而变化。这种现象导致槽绕组在不同运行状态下热点发生移动，而端部绕组则不那么明显。因此，固定热电偶无法始终准确检测槽绕组中的峰值温度，这一点从未被实现和重视。在本文中，我们分析了槽绕组和端部绕组中热点的运动。为了提高检测精度，我们使用离线理论热磁模型来推导各种工作状态下测量位置的温度与真实热点​​之间的关系。然后可以根据推导的关系实时校正热电偶读数。实验测试验证了该方法在提高峰值温度检测精度方面的性能。