Hu Zhen, Cui Man, Wu Xiaohua
College of Automation, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China.
Micromachines (Basel). 2023 Dec 28;15(1):0. doi: 10.3390/mi15010063.
As a core component of photovoltaic power generation systems, insulated gate bipolar transistor (IGBT) modules continually suffer from severe temperature swings due to complex operation conditions and various environmental conditions, resulting in fatigue failure. The junction temperature prediction guarantees that the IGBT module operates within the safety threshold. The thermal equivalent circuit model is a common approach to predicting junction temperature. However, the model parameters are easily affected by the solder aging. An accurate temperature prediction by the model is impossible during service. This paper proposes an improved thermal equivalent circuit model that can remove the effect of solder aging. Firstly, the solder aging process is monitored in real-time based on the case temperatures. Secondly, the model parameters are corrected by the thermal impedance from chip to baseplate based on the linear thermal characteristic. The simulation and experimental results show that the proposed model can reduce the temperature prediction error by more than 90% under the same aging condition. The proposed method only depends on the case temperatures to correct the model parameters, which is more economical. In addition, the experimental and simulation analysis in this work can help students of power electronics courses have an in-depth knowledge of power devices' mechanical structure, heat dissipation principles, temperature distribution, junction temperature monitoring, and so on.
作为光伏发电系统的核心部件，绝缘栅双极型晶体管（IGBT）模块由于复杂的运行条件和各种环境条件而持续遭受严重的温度波动，从而导致疲劳失效。结温预测可确保IGBT模块在安全阈值内运行。热等效电路模型是预测结温的常用方法。然而，模型参数很容易受到焊料老化的影响。在服役期间，通过该模型进行准确的温度预测是不可能的。本文提出了一种改进的热等效电路模型，该模型可以消除焊料老化的影响。首先，基于外壳温度实时监测焊料老化过程。其次，基于线性热特性，利用芯片到基板的热阻抗对模型参数进行校正。仿真和实验结果表明，所提出的模型在相同老化条件下可将温度预测误差降低90%以上。所提出的方法仅依赖于外壳温度来校正模型参数，更为经济。此外，本文的实验和仿真分析有助于电力电子课程的学生深入了解功率器件的机械结构、散热原理、温度分布、结温监测等。
