The Project MessLeha

WiPANO MessLeha

The MessLeha project analyzes measurement methods and environments for characterizing fast power semiconductors and develops a machine-readable data sheet for simulation tools.
[Photo: MessLeha - VDE DKE]

MessLeha

Runtime: 01.05.2020 – 31.12.2021

Partners: VDE DKE Deutsche Kommission Elektrotechnik, Infineon Technologies AG, PE-Systems GmbH, Physikalisch Technische Bundesanstalt, Universität Stuttgart (Institut für Robuste Leistungshalbleitersysteme und Institut für Leistungselektronik und Elektrische Antriebe)

Associated partners: ABB Power Grids Switzerland, REFU Drive, Rohde & Schwarz GmbH & Co. KG, Rohm Semiconductor GmbH, Fuji Electric Europe GmbH

For each power electronic system a selection of a suitable power semiconductor must be made from a very large solution space. In order to be able to compare the transistors with each other, data sheet values are usually taken to hand, which is done by characterizing the semiconductors. The measurement procedures are currently described in the IEC 60747 series of standards "Semiconductor devices - Single semiconductor devices". The switching energy and thus the switching losses of the semiconductors are usually determined with the aid of the double pulse test. The structure of this test is described in the mentioned standard.

Due to the increasing use of SiC and GaN semiconductors, which achieve significantly faster switching speeds, the influence of the measurement methodology and the setup, which are not defined in the standards, is becoming ever greater. Since fundamentally different measurement setups and measurement systems are used, the traceability and thus the comparability of the measurement results is not trivially given.

In addition, manufacturers often provide models that can only be used by a limited number of simulation tools. This limits the comparison of different components for the customer, since models that cannot be used must be created by complex parameterization due to the lack of tools.

The aim of the project is to submit the two draft standards to IEC. The draft standard on the characterization structure is intended to supplement the IEC 60747-8, -9 and -15 standards. The existing measurement environment will be adapted for accurate determinability of switching losses and applicability to future generations of devices (SiC and GaN) will be ensured.

The second draft standard on the machine-readable data sheet is intended to enable traceability and thus comparability of the measured components based on the data sheet information. For this purpose, a machine-readable data set is defined for use in all simulation tools. 


Source: https://www.dke.de/de/arbeitsfelder/components-technologies/messleha

Due to the fast switching times of Wide-Bandgap semiconductors, like SiC and GaN, the requirements of the equipment for the switching loss measurements are rapidly increasing in comparison to silicon devices.

The University of Stuttgart with its Institutes for Power Electronics and Electrical Drives (ILEA) and Robust Power Semiconductor Systems (ILH) is therefore working on improving and characterizing measurement setups for Wide-Bandgap switching loss determination. For this purpose, the existing state-of-the-art Double Pulse Test has been improved by new current sensors and high-accuracy characterization of current and voltage probes with regard to frequency behavior, i.e. bandwidth. Furthermore, the influence of the parasitics in the setup, like stray inductance, will be taken into account. The results are verified with the help of highly accurate calorimetric measurements, utilizing the heat-up phase for fast switching loss results at several points of operation.

In parallel, the National Metrology Institute of Germany (PTB) is developing a method for measuring the switching losses with a sampling measuring system. With this method, the voltage and the current will be recorded precisely during the switching time. For this purpose, the voltage divider and the shunt first need to be characterized. Another challenge is the time correction between the two recorded signals. These two factors ensure the accuracy of the calculated switching losses.

After the development phase of the three methods, a comparison will be performed between all methods. The measurement uncertainty of the systems will also be determined.

Contact

This image shows Dominik Koch
M.Sc.

Dominik Koch

Research Assistant

This image shows Julian Weimer
M.Sc.

Julian Weimer

Research Assistant

To the top of the page