Søren Jørgensen

Advanced Accelerated Power Cycling Test for Reliability Investigation of Power Device Modules

This paper presents an apparatus and methodology for an advanced accelerated power cycling test of insulated-gate bipolar transistor (IGBT) modules. In this test, the accelerated power cycling test can be performed under more realistic electrical operating conditions with online wear-out monitoring of tested power IGBT module. The various realistic electrical operating conditions close to real three-phase converter applications can be achieved by the simple control method. Further, by the proposed concept of applying the temperature stress, it is possible to apply various magnitudes of temperature swing in a short cycle period and to change the temperature cycle period easily. Thanks to a short temperature cycle period, test results can be obtained in a reasonable test time. A detailed explanation of apparatus such as configuration and control methods for the different functions of accelerated power cycling test setup is given. Then, an improved in situ junction temperature estimation method using on-state collector-emitter voltage VCE_ON and load current is proposed. In addition, a procedure of advanced accelerated power cycling test and test results with 600 V, 30 A transfer molded IGBT modules are presented in order to verify the validity and effectiveness of the proposed apparatus and methodology. Finally, physics-of-failure analysis of tested IGBT modules is provided.

Reliability Improvement of Power Converters by Means of Condition Monitoring of IGBT Modules

Power electronic systems have gradually gained an important status in a wide range of industrial applications such as renewable generation, motor drives, automotive, and railway transportation. Accordingly, recent research makes an effort to improve the reliability of power electronic systems to comply with more stringent constraints on safety, cost, and availability. The power devices are one of the most reliability-critical components in power electronic systems. Therefore, its condition monitoring plays an important role to improve the reliability of power electronic systems. This paper proposes a condition monitoring method of insulated-gate bipolar transistor (IGBT) modules. In the first section of this paper, a structure of a conventional IGBT module and a related parameter for the condition monitoring are explained. Then, a proposed real-time on-state collector–emitter voltage measurement circuit and condition monitoring strategies under different operating conditions are described. Finally, experimental results confirm the feasibility and effectiveness of the proposed method.

Condition monitoring of IGBT module for reliability improvement of power converters

Power electronic systems have gradually gained an important status in a wide range of industrial applications such as automotive, motor drives, railway transportation and renewable generation. Accordingly, recent research makes an effort to improve the reliability of power electronic systems to comply with more stringent constraints on safety, cost and availability. The power devices are the one of the most reliability-critical components in power electronic systems. Therefore, its condition monitoring plays an important role to improve the reliability of power electronic systems. This paper proposes a condition monitoring method of an IGBT module. In the first section of this paper, the structure of a conventional IGBT module and related parameter for the condition monitoring are explained. Then, an intelligent on-state collector-emitter voltage measurement circuit and condition monitoring strategies depending on converter operating conditions are described. Finally, experimental results confirm the feasibility and effectiveness of the proposed method.

Study on Effect of Junction Temperature Swing Duration on Lifetime of Transfer Molded Power IGBT Modules

In this paper, the effect of junction temperature swing duration on lifetime of transfer molded power insulated gate bipolar transistor (IGBT) modules is studied and a relevant lifetime factor is modeled. This study is based on 39 accelerated power cycling test results under six different conditions by an advanced power cycling test setup, which allows tested modules to be operated under more realistic electrical conditions during the power cycling test. The analysis of the test results and the temperature swing duration dependent lifetime factor under different definitions and confidence levels are presented. This study enables to include the t△ Tj effect on lifetime model of IGBT modules for its lifetime estimation and it may result in improved lifetime prediction of IGBT modules under given mission profiles of converters. A postfailure analysis of the tested IGBT modules is also performed.

Advanced power cycling test for power module with on-line on-state V CE measurement

Recent research has made an effort to improve the reliability of power electronic systems to comply with more stringent constraints on cost, safety, predicted lifetime and availability in many applications. For this, studies about failure mechanisms of power electronic components and lifetime estimation of power semiconductor devices and capacitors have been done. Accelerated power cycling test is one of the common tests to assess the power device module and develop the lifetime model considering the physics of failure. In this paper, a new advanced power cycling test setup is proposed for power module. The proposed concept can perform various stress conditions which is valid in a real mission profile and it is using a real power converter application with small loss. The concept of the proposed test setup is first presented. Then, the on-line on-state collector-emitter voltage VCE measurement for condition monitoring of the test device is discussed. Finally, a characterization method of test device regarding on-state VCE for junction temperature estimation is proposed. The experimental results of the prototype confirm the validity and the effectiveness of proposed test setup.

Junction temperature estimation for an advanced active power cycling test

On-state collector-emitter voltage (VCE) is a good indicator to determine the wear-out condition of power device modules. Further, it is a one of the Temperature Sensitive Electrical Parameters (TSEPs) and thus can be used for junction temperature estimation. In this paper, the junction temperature estimation method using on-state VCE for an advanced active power cycling test is proposed. The concept of the advanced power cycling test is explained first. Afterwards the junction temperature estimation method using on-state VCE and current is presented. Further, the method to improve the accuracy of the maximum junction temperature estimation is also proposed. Finally, the validity and effectiveness of the proposed method is confirmed by experimental results.

Effect of junction temperature swing durations on a lifetime of a transfer molded IGBT module

In this paper, the effect of junction temperature swing duration on the lifetime of a transfer molded Intelligent Power IGBT Module is studied and a relevant lifetime factor is modeled. A temperature swing duration dependent lifetime factor is defined based on 38 accelerated power cycling test results under 6 different conditions and it may improve a lifetime model for lifetime prediction of IGBT modules under various mission profiles of converters. The power cycling tests are performed by an advanced power cycling test setup which enables tested modules to be operated under more realistic electrical conditions during the power cycling test. The analysis of the test results and the temperature swing duration dependent lifetime factor under different definitions and confidence levels are presented.

Converter monitoring in a wind turbine application

Abstract Two Converter Monitoring Units (CMU) which were retrofitted in a multi Mega Watt wind turbine converter are presented. Synchronized sampling of semiconductor voltage (vceon) and semiconductor current (ic) enables the condition monitoring of the power modules. A vceon measurement circuitry for field operation is presented. A novel method of numerical integration of Rogowski coil voltage enables current sensing. Data from a whole year of operation show that the presented methods are consistent throughout long term operation, and that both the measurement principles and reference functions (model) are consistent during long time operation. It is thus expected that degradation of power modules and gate drives can be monitored.

Power cycling test of transfer molded IGBT modules by advanced power cycler under different junction temperature swings

Abstract In this paper, an effect of junction temperature swings (ΔTj) on reliability of IGBT modules is studied with 600 V, 30 A, transfer molded power modules. This study is based on power cycling test results of 18 IGBT modules under three different junction temperature swings, namely 40 °C, 60 °C and 70 °C, by means of an advanced power cycler. The advanced power cycler allows performing power cycling tests under similar conditions of IGBT modules in power electronics applications. This paper presents post-failure analysis of the tested IGBT modules of interest in order to investigate the failure mechanism and also to compare results under different Tj. Further, a lifetime factor in respect to ΔTj is modeled with different lifetime definitions and confidence levels. This paper enables a better understanding of the junction temperature swing-related failure mechanisms and reliability performance of transfer molded IGBT modules for power electronics applications.