This study investigates the degradation behavior and reliability of silicon carbide (SiC) MOSFETs under power cycling tests to address their vulnerability to thermo-mechanical stresses. Five 650V SiC MOSFETs (IMW65R107M1H) were subjected to controlled thermal cycles, and key parameters such as body diode voltage, thermal resistance, and junction temperature were monitored. The degradation mechanisms, including bond wire fatigue and gate oxide defects, were identified through abrupt and gradual changes in the body diode voltage. A Weibull distribution was used to model the component lifetime, estimating a B-10 lifetime of 7279 cycles for devices with varying ∆Tjbetween 120 °C and 140 °C. Furthermore, the body diode voltage and gate leakage current were highlighted as effective precursors for early failure detection. This research provides insights into improving SiC MOSFET reliability and lays the groundwork for early warning systems in high-power converter applications.

The Dual Active Bridge (DAB) is a popular DC-DC converter for bidirectional power transfer in applications such as the re-emerging technology of flow batteries. For such applications, it is essential to design the DAB for the wide voltage range operation of batteries, specifically focusing on its non-linear characteristics. The existing design methods utilise an optimisation algorithm to minimise the losses of the DAB at various equidistant voltage points in the voltage range. The resulting design is less efficient as it gives too much weight to insignificant operating points. This article proposes a new method that uses the flow battery characteristics to determine the operating points at which minimisation should be performed. The proposed method is validated with simulation results.

Power electronics converters (PEC) play a crucial role in interfacing renewable energy systems and electrolyzers to ensure a high production yield of green hydrogen. The design of such PEC is not straightforward due to the safety hazards of using multiple electrolyzer stacks and converter modules at industrial levels. Therefore, real-time simulations should be conducted to ensure the converter design satisfies all the requirements before deploying it on-site. This paper presents a real-time digital twin (RTDT) of a 10 kW dual-active bridge converter interfaced with an electrolyzer. OPAL-RT simulator (eHS toolbox) is used for RTDT. Finally, the voltage across the series inductance and current flowing through it are presented for the open-loop operation of DAB.

Electrolysis requires a high DC current at low voltage to produce hydrogen from water. Designing power converters for such a load requirement could be challenging while fulfilling the galvanic isolation needs. Therefore, prior knowledge of the electrolyzer's impact on the converter operation should be needed. In this context, this paper investigates the behavior of the Dual Active Bridge (DAB) converter when utilized for electrolysis. A MATLAB simulation of DAB with a 10 kW alkaline electrolyzer is developed. Several converter parameters, such as the phase shift angle, series inductance, peak and RMS currents, and voltage gain, are analyzed during electrolysis. Distinct operating behavior is observed from the analysis.

The small, light-weight and modular Lunar rover must survive several earth days in harsh environment after its moon landing. Its power electronic system with integrated solar generation needs power for its mission and also to stay warm in very cold temperatures of the moon. This paper presents the design of the power electronic system of the Lunar Zebro rover. Two topologies are compared that result from using a 12 V bus and 24 V bus. The design of the DC/DC converters required is presented for CCM and DCM operation. The losses in the DC/DC converters operating in CCM and DCM are calculated for the two bus voltages to determine the mode of operation and bus voltage that results in the highest efficiency. Further, the average power loss during operation of the rover is estimated for both bus voltages. Operating the DC/DC converters in CCM using a 12 V bus results in the lowest losses.

EV fast chargers are essential in addressing the concern of limited driving range for E-mobility applications. However, the load profile of a converter for fast charging involves a high-current pulse that can last for a few minutes to efficiently replenish the EV battery, which is followed by a cooldown period after the charging process is finished. This results in thermal cycles that can lead to thermo-mechanical fatigue and degradation of power electronic components, thereby impacting device lifetime. This paper presents a comparative study on the reliability of power devices in isolated half-bridge and full-bridge DC-DC converters in EV fast chargers. The study focuses on the differences in thermal stresses that Si switches experience in each converter during charging cycles and how it impacts the end-of-life of each device. This study provides valuable insights for selecting reliable power converters for EV fast charging applications.

The reliability of semiconductor power devices can be studied by performing a thermal and power cycling test. In order to create the desired temperature cycles, there are four free variables to select during the power cycling test, namely the heating current, heating time, cooling time, and heatsink temperature. In this paper, the relation between the selected variables and the minimum and maximum junction temperature is extensively tested for the silicon IGBT with serial number IKP06N60T. Furthermore, the thermal model is discussed and verified and a rough estimate of the electrical resistance, thermal time constant, thermal resistance, and thermal capacitance are calculated.

Back-To-Back (B2B) Voltage Source Converter (VSC) with AC-side LCL filters can be adopted for parallel AC-DC distribution links. In this paper, Grid-side Current Control (GCC) for the inner/fast control loops of the front- and backend power electronics are implemented in order to enhance the system performance against grid disturbances. Herein, a notch filter-based GCC scheme with a harmonic rejection control is proposed which is able to deliver attenuation to the LCL filter resonances while suppressing the harmonics in the grid-side currents originated when the AC voltages are distorted. The results obtained in MATLAB/SIMULINK and an experimental prototype show that the studied GCC method can successfully mitigate the influence of grid voltage harmonics, while providing a stable power control for the hybrid AC-DC distribution links.