The Algorithm And Software Implementation Of The Thermal Transient Test Technology Applied In High Power IGBT Devices

With the development of power system,the power density of IGBT devices is gradually increased and the working environment is more complex,and this makes the thermal reliability of IGBT devices become increasingly prominent.Thus,It is very important to accurately measure the thermal characteristics parameters of IGBT devices.The traditional thermal resistance test method can only measure the overall thermal resistance of the device,which limits the further thermal analysis of the device.The thermal transient test technology based on the structure function can fully analyzes the thermal properties of each layer from the chip to the heat sink.Hence,studying the thermal transient test technology of high power IGBT devices has important theoretical and practical significance.First of all,this paper outlines the research status of the test methods and test systems of thermal characteristics of high power IGBT devices at home and abroad.Aiming at the two main thermal characteristic parameters:junction temperature and thermal resistance,the common test methods and the related thermal characteristics tester is briefly introduced.In order to overcome the shortcomings of the traditional thermal characteristics testing technology,this paper focuses on the thermal transient testing technology,and researches its basic principle in detail.Meanwhile,a software testing system is set up to accurately measure the thermal parameters of the various layers of the device.Then,in view of the two key issues of thermal transient testing technology,this paper studies the basic principles and influencing factors of two commonly used deconvolution algorithms,and compares the performance of the algorithm in all aspects.For the most suitable deconvolution algorithm,this paper gives a correct evaluation.At the same time,it is proposed that Mathematica can be used to solve the problem of accuracy in the process of network model conversion.Simulation results show that using Mathematica can achieve the same precision as GMP and reduce the difficulty of conversion,which is more conducive to its popularization and application in the thermal characteristic test of power semiconductor devices.Finally,taking the ideal thermal circuit model and the actual test data of the power semiconductor device as an example,the accuracy and operability of the proposed algorithm are verified.In addition,applying the finite element model of the pressure-packed IGBT device to test the feasibility and effectiveness of the method for implementing thermal transient testing of high power IGBT devices proposed in this paper.