Fig 17 - uploaded by Kristian Bonderup Pedersen
Content may be subject to copyright.
Source publication
Several accelerated test methods exist in order to study the failures mechanisms of the high power IGBT modules like temperature cycling test or power cycles based on DC current pulses. The main drawback is that the test conditions do not represent the real performance and stress conditions of the device in real application. The hypothesis is that...
Similar publications
This paper brings the development of new alternatives for the Burndown, a graphic tool used to monitor and follow-up a project. In its traditional form this graphic estimates linear wane of the development in each cycle of a project. The problem comes up when the team does not have a development pace as linear as the graphic draws. To solve this pr...
This report to examines patterns in phytoplankton and zooplankton based on a subset of Minnesota's Sentinel Lakes and serves as a baseline for future monitoring and analysis. This analysis provides basic descriptions of phytoplankton and zooplankton composition, seasonal cycling, and interactions in 13 Sentinel Lakes, which represent a range of tro...
Citations
... IGBT power modules are always conducted and loaded with periodic DC current to generate a cyclic temperature, which accelerates the aging of the module. However, in real applications, PWM (Pulse Width Modulation) is generally used to control the gate of the IGBT to control its switching state [6]. In this case, the IGBT module is actively switched by itself, therefore not only conduction losses but also switching losses are generated during switching process. ...
PWM power cycling, which has complex control strategies and high testing costs, received a lot of attention in recent years due to the test conditions are closer to the application of power modules than standard DC power cycling. Therefore, the root difference of the failure modes and lifetime of IGBT power modules between DC and PWM power cycling is the concern in this paper, based on the finite element simulation. For stimulating the PWM power cycling with high accuracy and fast speed, an IPWM power cycling is proposed and verified by a simple model. Then an electro-thermo-mechanical coupled model of a single chip is established for comparison. Mainly focus on the current distribution, temperature distribution and stress distribution. The current distribution comparison results show no difference while a higher temperature gradient is shown in PWM power cycling due to the additional switching losses. However, the stress distribution results show chip solder layer is still the main failure mechanism both in DC and IPWM power cycling. Therefore, a conclusion can be obtained that there is no difference in failure mechanism and lifetime between DC and PWM power cycling. And the same bond wire failure and similar lifetime of DC and PWM power cycling tests further verify this conclusion.
... The prototype of the aging test setup with online V ds real-time monitoring circuit is shown in Fig. 3. Fig. 4 shows the principle of V ds measurement, which was based on the desaturation protection measurement [18]. The operational principle and design details are introduced in [18] and [19]. ...
... The prototype of the aging test setup with online V ds real-time monitoring circuit is shown in Fig. 3. Fig. 4 shows the principle of V ds measurement, which was based on the desaturation protection measurement [18]. The operational principle and design details are introduced in [18] and [19]. Diodes D1 and D2 are connected in series, and these diodes are forward biased by the current source when MOS-FET is ON. ...
... Schematic of measurement principle for measuring the ON-state voltage drop of SiC MOSFET[18]. ...
The reliability concern of SiC MOSFETs has been extensively investigated with various accelerated stress tests. However, these conventional tests are predominantly performed in a simplified and controlled testing environment, which might or might not realistically simulate the actual device operation profiles in power converters. In this paper, we report the long-term degradation phenomenon of several types of SiC MOSFETs in an actual 2kW Power Factor Correction (PFC) converter and provide an analysis of the degradation mechanisms. Compared to conventional DC power cycling tests, a large decrease in threshold voltage was observed due to gate oxide degradation of SiC MOSFET in the PFC converter. Online monitoring results show that the on-state voltage drop of SiC MOSFET continuously rises with the increase of stress times. The increase in on-state voltage is caused by the change of package resistance and channel resistance. Gate oxide degradation resulting in a large increase in drain-source leakage current and gate leakage current. Meanwhile, the variation of miller plateau voltage and threshold voltage results in a significant change of turn-on losses in SiC MOSFET. TCAD simulation and C-V measurement indicate that the main degradation mechanism is hot holes accumulate within the gate oxide above the JFET region and channel region due to high electric field stress.
... Therefore, the existing model is not fully applicable when the actual field operation conditions have been changing, which is exactly the case of the TC application. For example, in actual TC operation, due to the movement of EMU, the switching device undergoes changing ambient temperature, while the ambient temperature remains constant in AFT [18]; moreover, the switching frequency (i.e., the number of turns on and off in one second) and the current of the switching device continuously change with the change of EMU speed or passenger capacity, while the traditional AFT only considers constant switching frequency and constant test current [19] [20]. This paper tries to put forward an on-line estimation method and prediction scheme for Fatigue Grade of switching devices, which is suitable for the application of a traction converter of EMU. ...
It is difficult to estimate and predict the fatigue state of switchgear in traction converter of urban Electric Multiple Unit (EMU). At the same time, this is just the purpose of this paper. Firstly, the power loss and junction temperature of the device are analyzed by using the results of electro-thermal simulation and actual working conditions. Then, a novel Bi-directional accelerated fatigue test (BAFT) is proposed, and the data obtained from BAFT are used to establish a fitting fatigue model for a specific switch device. BAFT data enable the fatigue interaction between Insulated Gate Bipolar Transistor (IGBT) and Free Wheeling Diode (FWD) to be displayed in the common switching device module, and the interaction is represented by an acceleration factor. In the fatigue model, the service life and fatigue state of the equipment is related to the equivalent fatigue current which is used to generate the fatigue. The equivalent fatigue current is observed by the proposed analysis identification model. The historical data of fatigue values are subjected to Gray Model (GM) (2, 1) for trend prediction, and then the service time of the switch device is calculated using the predicted fatigue values from GM (2, 1). The examples presented in this paper are based on recorded field data.
... The switching device in the TC is usually a package module composed of an IGBT and an FWD. The fatigue of the switching device is mainly manifested by package failure, including two main forms：Wire liftoffs and solder layer cracking [4,5]. Wire liftoffs and solder layer cracking are caused by shear thermal stresses that are produced by temperature drift inside the device. ...
... An AFT tests a DUT with a predetermined time-effect force and obtains data showing the fatigue characteristics of it. However, the existing fatigue model requires stable and fixed operating conditions because these models were established under the AFT results of fixed experimental conditions [4,11,12]. Therefore, the existing model cannot be fully applied to the changing conditions of the actual operating conditions, and this is the actual application of the TC. For example, in practical TC operation, the switching device is affected by the changing ambient temperature due to the movement of the EMU, while the ambient temperature remains constant in AFT [13]; in addition, the switching frequency of the switching device (i.e. ...
... As stated above, the IGBT ages faster with the FWD actions, i.e. the fatigue process is accelerated. If the aging state of the DUT is still represented by the aging state of the IGBT (as is the case in the existing references [2][3][4]), this acceleration effect of the FWD action must be considered. ...
The switching device is relatively weakest in the traction converter, and this paper aims at the fault prediction of it. Firstly, the mathematical distribution is analyzed based on the results that were obtained in electro thermal simulation and a single-directional accelerated fatigue test. Then, the accelerated fatigue test with bi-directional fatigue current is proposed, the data from which reflects the accelerating effect from FWD on the device aging process. The analytical model of fatigue process is fitted with the data that were obtained in the test. In order to shorten the test time consumption, we propose a weighted least squares method (LSM) to fit the failure data. Finally, the prediction model is presented with the consideration of fatigue signature and Arrhenius temperature factor.
... The degrees of influence of the electro-thermal parameters on the junction temperature and the case temperature are analyzed by putting the electro-thermal parameters of different aging states into the electrothermal coupling model. The power module model for the power thermal cycling test is MMG75S120B6HN [24,25]. During the test, the gate-to-emitter voltage was maintained at Vge = 15 V, and a constant current of 75 A was applied to the power module using a programmable DC power supply. ...
... The degrees of influence of the electro-thermal parameters on the junction temperature and the case temperature are analyzed by putting the electro-thermal parameters of different aging states into the electro-thermal coupling model. The power module model for the power thermal cycling test is MMG75S120B6HN [24,25]. During the test, the gate-to-emitter voltage was maintained at V ge = 15 V, and a constant current of 75 A was applied to the power module using a programmable DC power supply. ...
In the exploration of new energy sources and the search for a path to sustainable development the reliable operation of wind turbines is of great importance to the stability of power systems. To ensure the stable and reliable operation of the Insulated Gate Bipolar Transistor (IGBT) power module, in this work the influence of changes with aging of different electro-thermal parameters on the junction temperature and the case temperature was studied. Firstly, power thermal cycling tests were performed on the IGBT power module, and the I-V characteristic curve, switching loss and transient thermal impedance are recorded every 1000 power cycles, and then the electrical parameters (saturation voltage drop and switching loss) and the thermal parameters (junction-to-case thermal resistance) of the IGBT are obtained under different aging states. The obtained electro-thermal parameters are substituted into the established electro-thermal coupling model to obtain the junction temperature and the case temperature under different aging states. The degrees of influence of these electro-thermal parameters on the junction temperature and case temperature under different aging states are analyzed by the single variable method. The results show that the changes of the electro-thermal parameters under different aging states affects the junction temperature and the case temperature as follows: (1) Compared with other parameters, the transient thermal impedance has the greatest influence on the junction temperature, which is 60.1%. (2) Compared with other parameters, the switching loss has the greatest influence on the case temperature, which is 79.8%. The result provides a novel method for the junction temperature calculation model and lays a foundation for evaluating the aging state by using the case temperature, which has important theoretical and practical significance for the stable operation of power electronic systems.
... These parameters are widely used in the literature [27] [39] [58] [59] [60], where the ageing monitoring is done periodically in an accelerated ageing test bench, directly after each accelerated ageing phase. Inversely, the monitoring of these electrical parameters can be done online also, during the functioning of the inverter, as proposed in [61]. ...
... Accordingly, the value of in the case of MOSFET 3 crosses the commonly used threshold value, corresponding to an increase of 20% above the initial value. The increase of this parameter can be considered as indicator of the wire bonding lift off, a reconstruction of the metallization surface [37] [61], a decrease in device's thermal performances, and/or a degradation of the die given that ℎ has also increased. It should be noted that showed close evolution as that of , being not represented here. ...
... The electrical diagram of the ageing test bench is based on a single-phase inverter feeding a pure inductive load (Fig. 6.1). As represented in Fig. 6.2 and as proposed in [58] and [61], this inverter is successively used for monitoring the condition of the semiconductor devices, and for accelerating their ageing by applying the same method represented in Chapter 5. A relaxation phase is added between the production/ageing and the monitoring phases, by stopping the inverter during several tens of minutes in order to decrease the devices' temperature [123] [124]. When a damage indicator crosses a defined damage threshold, the accelerated ageing is stopped. ...
Dans le cas des installations photovoltaïques, l’onduleur est le premier élément défaillant dont il est difficile d’anticiper la panne, et peu d’études ont été faites sur la fiabilité de ce type de convertisseur. L'objectif de cette thèse est de proposer des outils et méthodes en vue d'étudier le vieillissement des modules de puissance dans ce type d'application en se focalisant sur les phénomènes de dégradation liés à des aspects thermomécaniques.En règle générale, le vieillissement accéléré des modules de puissance est effectué dans des conditions aggravées de courant (Cyclage Actif) ou de température (Cyclage Passif) pour accélérer les processus de vieillissement. Malheureusement, en appliquant ce type de vieillissement accéléré, des mécanismes de défaillances qui ne se produisent pas dans la vraie application peuvent être observés et, inversement, d'autres mécanismes qui se produisent habituellement peuvent ne pas apparaître.La première partie de la thèse se focalise donc sur la mise en place d'une méthode de vieillissement accéléré des composants semi-conducteurs des onduleurs photovoltaïques. Cela est fait en s’appuyant sur l’analyse des profils de mission du courant efficace de sortie des onduleurs et de la température ambiante, extraits des centrales photovoltaïques situées au sud de la France sur plusieurs années. Ces profils sont utilisés pour étudier les dynamiques du courant photovoltaïque, et sont introduites dans des modèles numériques pour estimer les pertes et les variations de la température de jonction des semi-conducteurs utilisés dans les onduleurs, en utilisant l’algorithme de comptage de cycles "Rainflow".Cette méthode est ensuite mise en œuvre dans deux bancs expérimentaux. Dans le premier, les composants sous test sont des modules IGBT. Les composants sont mis en œuvre dans un banc de cyclage utilisant la méthode d'opposition et mettant en œuvre le profil de vieillissement défini précédemment. Un dispositif in-situ de suivi d'indicateurs de vieillissement (impédance thermique et résistance dynamique) est également proposé et évalué. Le deuxième banc est consacré à l'étude de modules de puissance à base de MOSFET SiC. Le vieillissement est effectué dans les mêmes conditions que pour les modules IGBT et de nombreux indicateurs électriques sont monitorés mais, cette fois ci, en extrayant les composants de l'onduleur de cyclage.Les résultats obtenus ont permis de déterminer des indicateurs de vieillissement d’IGBT et de MOSFET SiC utilisés dans un onduleur photovoltaïque. De plus, un prototype d’un système de suivi in-situ de l’état de santé d’un onduleur en monitorant automatiquement la tension directe, la résistance dynamique et l’impédance thermique des composants semi-conducteurs est proposé.
... If the rated power of the target module is high, it is difficult to find power device modules, which have higher rated power than the target module for the load converter. In this case, the topology can be altered as shown in Fig. 15 (b) for a single-phase system [58] and for 3-phase system as shown in Fig. 15 (c), where two load modules are operated by the same gate signal so that the half of load current flows in each load module [59]. ...
... Fig. 15. Modified AC power cycling test topologies for different power device modules (a) single phase PC test system [18] (b) single phase PC test system for high rated power device modules [58] (c) 3-phase PC test system for high rated power device modules [59]. ...
Power cycling test is one of the important tasks to investigate the reliability performance of power device modules in respect to temperature stress. From this, it is able to predict the lifetime of a component in power converters. In this paper, representative power cycling test circuits, measurement circuits of wear-out failure indicators as well as measurement strategies for different power cycling test circuits are discussed in order to provide the current state of knowledge of this topic by organizing and evaluating current literature. In the first section of this paper, the structure of a conventional power device module and its related wear-out failure mechanisms with degradation indicators are discussed. Then, representative power cycling test circuits are introduced. Furthermore, on-state collector-emitter voltage (V
<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CE ON</sub>
) and forward voltage (V
<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">F</sub>
) measurement circuits for wear-out condition monitoring of power device modules during power cycling test are presented. Finally, different junction temperature measurement strategies for monitoring of solder joint degradation are explained.
... Presently, the device under test bridge is operated in generator mode, thus, the diodes are stressed the most. For details concerning the power cycling setup see [6,21]. ...
In this paper the degradation evolution and distribution in high power IGBT module interconnects are investigated. Modules are subjected to advanced active thermal cycling by applying a sinusoidal current load switched by the device. A series of samples subjected to an increasing number of power cycles under conditions resembling real life operation are considered. Under the given load conditions the dominating failure mechanisms are bond wire lift-off and metallization reconstruction. Both failure processes are investigated using micro-sectioning approach and scanning electron microscopy combined with focused ion beam milling. The degradation evolution and distribution are analysed and discussed in relation to load conditions. It is clear that both bond wire lift-off and metallization reconstruction are complicated micro-structural processes affected by numerous stressors. Especially, the fractures causing bond wire lift-off are observed to consist of several sub-phases—delamination, intergranular, and transgranular crack propagations.
... In the future this could be an approach for understanding on-line monitoring results, e.g. like changes in the forward voltage [16]. Additionally, it can provide validation of online monitoring strategies for live degradation assessment [17], as well as quantify degradation mechanisms from an electrical point of view. ...
... All load parameters are kept close to realistic operating regime at an accelerated level to obtain device degradation. The setup is described in detail in [16,18,20]. ...
... revealed wire lift-off which is found to be the dominating failure for LS diodes (see Table 3). This tendency is consistent with the change in forward voltage measured during the power cycling presented in [16]. ...
... catastrophic failure. Detailed information on online monitoring methodologies, power cycling setup, and visual inspection results are available in [5], [19], [17]. Following power cycling the modules were experimentally investigated by fourpoint probing [20], [21] of electrical parameters and microinvestigation using SEM/FIB and micro-sectioning [14]. ...
... By investigation of micro-structure a clear tendency of increased degradation in stitch bondings compared to edge bondings is observed and centre wires on diodes are displaying significant wear. For additional information see [19], [22]. ...
... The accelerated test setup was designed to apply a sinusoidal load similar to real life conditions with equally distributed power loss between similar components -which initially was the case. Over time, however, the LS diode displayed clear tendencies of increased stress -increase in forward voltage, and material changes from visual inspection after testing, see [17] and [19], respectively. This problem was through the temperature simulation alone, see Fig. 9, identified to be directly related to local temperature. ...
A degradation model investigating the electrothermo- mechanical fatigue, experienced by insulated gate bipolar transistors modules, is presented. To illustrate the concept a specific case of power modules subjected to active power cycling which induce failure through bond wire lift-off is considered. Bond wire lift-off is believed to be due to thermally induced stress arising from a mismatch in the coefficients of thermal expansion between the wires and the given substrate. Overall, the theoretical evaluation is based on determining the thermo-mechanical stress around the bond wire/substrate interface through multiphysics based models. The simulation detail and included equations are specified according to region of interest and their complexity. In common, however, is the use of the finite element method combined with empirical equations. The final result is a numerical approach to evaluate the damage accumulated by a given load which may be used for prediction of lifetime or optimization of work points and module geometry.
