0000000000043027
AUTHOR
D. Gilabert
showing 8 related works from this author
Impact of Gamma Radiation on Dynamic RDSON Characteristics in AlGaN/GaN Power HEMTs
2019
GaN high-electron-mobility transistors (HEMTs) are promising next-generation devices in the power electronics field which can coexist with silicon semiconductors, mainly in some radiation-intensive environments, such as power space converters, where high frequencies and voltages are also needed. Its wide band gap (WBG), large breakdown electric field, and thermal stability improve actual silicon performances. However, at the moment, GaN HEMT technology suffers from some reliability issues, one of the more relevant of which is the dynamic on-state resistance (R) regarding power switching converter applications. In this study, we focused on the drain-to-source on-resistance (R) characteristic…
Power system consumption model using SPICE
2014
Space missions have very stringent mass, volume and also power budgets. This requires very precise knowledge of the power consumption of the whole satellite, not only peak power but also static and long term dynamic power. This calculation becomes very complex if all the operational modes (long term dynamic changes) are taken into account, including the different environmental situations. The power budget of any Power Converter Module (PCM), which includes not only the DC/DC converter but also the distribution unit, depends on the power it delivers and on external factors like temperature and input voltage. We propose to use a linear SPICE model using electronic models of discrete component…
Failure Rate Measurement on Silicon Diodes Reverse Polarized at High Temperature
2017
This paper calculates the failure rate on reversed polarized silicon diodes with the aim to justify, experimentally, the rules of the European Space Agency (ESA) which are referred to the component life’s extension, the reliability increase and the end of life performance enhancement, by using oversized devices (derating rules). In order to verify the derating rules, 80 silicon diodes are used, which are reverse polarized in a high temperature environment. The diodes are divided in 4 groups of 20 diodes, applying a different voltage to each group, in order to relate the failure rate to the applied derating rule. The experiment described in this paper is developed using a temperature acceler…
Output Impedance Improvement Using Coupled Inductors
2017
When using a single DC/DC converter with multiple outputs and having a buck topology, which has one filter inductor per output, the designer can choose to couple these outputs together. This paper demonstrates additional benefits of coupling output inductors together. Apart from saving mass and volume, and due to an improved small signal behaviour it also reduces the output impedance of the regulated output. The paper will analyse a seven output push-pull converter used as a space power converter module and verify the theoretical results with experimental measurements.
Dynamic $\mathrm{R}_{\mathrm{ON}}$ evaluation of commercial GaN HEMT under different switching and radiation conditions
2019
This paper focus on the study of dynamic resistance $(\mathrm{R}_{\mathrm{dyn}})$ over commercial Gallium Nitride High Electromobility Transistors (GaN HEMTs) devices. The first part shows a study of the main mechanism causing $\mathrm{R}_{\mathrm{dyn}}$ , showing that depending on the structure, stress time, voltage applied and switching conditions, the $\mathrm{R}_{\mathrm{dyn}}$ can suffer a relevant increase. Also, it is demonstrated how the use of soft-switching conditions can alleviate trapping effects. Finally, due to the interest over these devices for future space applications, the effects of gamma radiation over the $\mathrm{R}_{\mathrm{dyn}}$ has been studied.
Design of Zero-Ripple-Current Coupled Inductors With PWM Signals in Continuous Conduction Mode
2021
Coupled inductors are widely used in multiple outputs and interleaved dc–dc converters. Also filters often use coupled inductors as their inductive part. A generalized design procedure is proposed in this article focused on current ripple minimization and applicable to coupled inductors exposed to pulsewidth modulation signals and in continuous conduction mode. The design provides a very large inductance for all windings but one. Compared to other designs, it adapts to the existing magnetic properties of the magnetic device changing only the inductance ratio, simplifying the design and manufacturing process. It is based on the equivalent inductance value and its divergences. The only assump…
Zero Ripple Current with Coupled Inductors in Continuous Conduction Mode under PWM Signals
2020
This article presents a generalized analysis to explain current ripple of an $m$ windings coupled inductor with a given coupling factor $k_{ij}$ for each pair of windings and then studies more in detail its use in the continuous conduction mode and with pulsewidth modulated signals. To determine the current ripple, a generalized expression of the equivalent inductance of each winding is calculated, including the influence of voltage unbalance. In the ideal case, the equivalent inductance shows that the current ripple can only become $m$ times smaller than that with uncoupled inductors. But in the unbalanced case, some divergences of the equivalent inductance appear that are responsible for …
Multi-pulse characterization of trapping/detrapping mechanisms in AlGaN/GaN high electromobility transistors
2019
GaN high-electro mobility transistors (HEMTs) are among the most promising candidates for use in high-power, high-frequency, and high-temperature electronics owing to their high electrical breakdown threshold and their high saturation electron velocity. The applications of these AlGaN/GaN HEMTs in power converters are limited by the surface trapping effects of drain-current collapse. Charge-trapping mechanisms affect the dynamic performance of all GaN HEMTs used in power switching applications. This study analyzes the dynamic resistance of GaN HEMTs and finds that the effects of dynamic resistance can be suppressed by controlling switching conditions and on-off cycles.