Press-pack insulated gate bipolar transistors (PP IGBTs) is well suited for high-voltage, high-power applications due to their double-side cooling, ease of series connection, and higher power density. It is very important to measure the junction-to-case thermal resistance ( R _thjc ) for evaluating thermal performance, with high accuracy. However, the existing thermal resistance test methods will have the problem of low accuracy when it is used in PP IGBTs. In this article, a new thermal resistance test method is proposed based on the transient dual-interface method (TDIM), different from traditional TDIM, which can obtain two transient thermal impedance ( Z _th ) curves without disassembling the fixture, and determine the R _thjc through the separation point. The 4500 V 3000 A StakPak PP IGBTs is used as the measurement object. The results show that compared with the traditional TDIM, the new method is very simple to operate, and the test results are more accurate than thermocouples, which is more suitable for PP IGBTs. The single-side thermal resistance of the PP IGBTs is analyzed, and the emitter side is even worse due to the disc spring. The R _thjc calculated by single-side thermal resistance is close to the proposed method, but fluctuates widely.

中文翻译：

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高功率压接式 IGBT 的替代结壳热阻测试方法


压装式绝缘栅双极晶体管 (PP IGBT) 具有双面冷却、易于串联和更高的功率密度，非常适合高压、高功率应用。高精度测量结壳热阻 (R thjc ) 对于评估热性能非常重要。然而，现有的热阻测试方法在应用于PP IGBT时会存在精度较低的问题。本文提出了一种基于瞬态双界面法（TDIM）的新热阻测试方法，与传统TDIM不同，无需拆卸夹具即可获得两条瞬态热阻（Z th ）曲线，并确定R thjc 通过分离点。使用 4500 V 3000 A StakPak PP IGBT 作为测量对象。结果表明，与传统的TDIM相比，新方法操作非常简单，测试结果比热电偶更准确，更适合PP IGBT。分析了PP IGBT的单侧热阻，发射极侧由于碟形弹簧的影响更差。单侧热阻计算的R thjc 与本文方法接近，但波动较大。