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Silicon carbide (SiC) based power semiconductor devices are now considered as key components for future power applications where high power density, high temperature, and high ruggedness against radiation are key parameters, thanks to the exceptional material properties including lower conduction and switching losses offered by the SiC devices. This paper deals with static and dynamic measurements performed for SiC-based bipolar junction transistors power modules with voltage rating 1200 V and current rating 800 A. The power modules are fabricated in flexible half-bridge configuration in order to allow either full power module with 2400 V and 800 A as one power switch or by using two parallel 1200 V and 400 A half-bridge legs. Results from engineering samples show overall good confidence as promised by the manufacturer for most of the transistor samples. A 40–50% reduction in the current gain was observed when temperature was increased to 475 K as expected. Bipolar devices have been found out fairly stable under continuous static operation at nominal current levels. [ABSTRACT FROM AUTHOR]

In high-power converter design, insulated gate bipolar transistor (IGBT) modules are often operated in parallel to reach high output currents. Evaluating the electrical and thermal behavior of the parallel IGBTs is crucial for the design and reliable operation of converter systems. This paper investigates the static and dynamic characterization of parallel IGBTs and the influence of the electrical parameters on the IGBT behavior. Si-based IGBT power modules with voltage rating of 4.5 kV and current rating of 1 kA are used for the experimental evaluation of module parallel connections. Parallel-connected modules have been driven by several commercial IGBT gate units at various dc-link voltages and current levels and with different temperatures. The tested IGBT gate units show good current sharing performance between the two parallel modules. Other important influencing factors such as busbar design layout, stray inductance variation, and gate driving are also investigated for parallel connections of IGBT modules. Finally, the switching energy of the parallel modules is extracted for IGBTs and diodes under different conditions. [ABSTRACT FROM AUTHOR]

The exigency of characterizing high-power insulated-gate bipolar transistors (IGBTs) directly on-site increasingly emerges in field installations hosting multilevel converters that employ such devices by the dozen, when not by hundreds, as it is already the reality for modern modular voltage-source HVDC and flexible ac transmission systems (FACTS). Nonetheless, differently from the actualities in permanent laboratories, the typology of the instrumentation rapidly obtainable on the field is often rather restricted by the aspects of logistic, necessary timing of intervention, and ruggedness against the usually harsh environments. Commonly, the only specimens realistically expectable at short notice on a field installation are portable curve tracers (CTs), portable field oscilloscopes with nonisolated channels, passive voltage probes, current probes based on Rogowski coils, portable multimeters, and variable dc power supplies. This paper describes metrological methodologies devised to diagnose and characterize high-power IGBTs by employing solely such a limited set of instruments. The severely erroneous conclusions that possibly descend from the utilization of CTs only are highlighted, both by experiments and by a dynamic model deduced from the nature of the specific metrological context. It is shown how the additional presence of properly connected oscilloscopes and probes becomes mandatory in order to attain a proper characterization. The role of the CTs should be strictly limited to mere stimuli generators only, also because their compensation techniques against the systematic measurement errors occurring with signal and low-power transistors rarely suffice in the case of high-power devices. Additionally, the equivalent differential capacitance between the collector and emitter terminals of a high-power IGBT–diode module is characterized too. It is often insufficiently documented in the datasheets, although its values and evolution are important for the dynamics of the commutation. Experimental observations from an ABB 5SNA 1200G450300 IGBT module (4.5 kV and 1.2 kA) are discussed throughout the different sections in order to elucidate the details of the presented methodologies. [ABSTRACT FROM PUBLISHER]

This paper deals with the evaluation of robustness of high-power press-pack insulated-gate bipolar transistor modules under short-circuit conditions. The severity of the tests is usually related to the achievement of the real failure mode which drives the device to withstand a big amount of energy. The most well-known methods to evaluate the robustness of the devices have been analyzed and improved in order to operate with the highest achievable di/dt and to consequently emulate the real circuit setup and failure mode. Experimental tests will be shown and evaluated under different voltage and temperature conditions. The tests described in this paper have been targeted to evaluate the capability of the device to withstand extremely severe conditions when they are used in a high-power converter. A driving protection feature dealing with the target of improving the functionality of protection against failure will be also described. [ABSTRACT FROM PUBLISHER]

In this paper, a physical model for a SiC Junction Field Effect Transistor (JFET) is presented. The novel feature of the model is that the mobility dependence on both temperature and electric field is taken into account. This is particularly important for high-current power devices where the maximum conduction current is limited by drift velocity saturation in the channel. The model equations are described in detail, emphasizing the differences introduced by the field-dependent mobility model. The model is then implemented in Pspice. Both static and dynamic simulation results are given. The results are validated with experimental results under static conditions and under resistive and inductive switching conditions. [ABSTRACT FROM AUTHOR]