Armin Jafari

This person has left EPFL

About
Privacy
Disclaimer

Graph Chatbot

Related publications (31)

Page 2 of 2

Impact of Embedded Liquid Cooling on the Electrical Characteristics of GaN-on-Si Power Transistors

Elison de Nazareth Matioli, Luca Nela, Remco Franciscus Peter van Erp, Armin Jafari, Palliyage Srilak Nirmana Perera, Catherine Erine

Wide-Band-Gap semiconductors have enabled considerable miniaturization of power devices, which requires, however, new thermal management solutions to handle the resulting high heat fluxes. Recently, embedded liquid cooling in GaN-on-Si devices was demonstr ...

Institute of Electrical and Electronics Engineers2021

Active-Device Losses in Resonant Power Converters: A Case Study with Class-E Inverters

Elison de Nazareth Matioli, Remco Franciscus Peter van Erp, Armin Jafari, Palliyage Srilak Nirmana Perera

Recent research has reported an undesirable OFF-state loss in high-frequency soft-switching power converters, such as resonant converters. This loss is attributed to a hysteresis loss related to the charging-discharging process of the output capacitance of ...

IEEE2021

Enhanced-DAB Converter: Comprehensive Design Evaluation

Elison de Nazareth Matioli, Armin Jafari, Mohammad Samizadeh Nikooytabalvandani

Soft switching in dual-active-bridge (DAB) converters enables their efficient operation at high frequencies, where the reduction in the size of magnetic components could result in ultra-high power densities. Nonetheless, losing soft-switching at high frequ ...

IEEE2021

Efficient High Step-up Operation in Boost Converters Based on Impulse Rectification

Elison de Nazareth Matioli, Armin Jafari, Palliyage Srilak Nirmana Perera

Conventional boost converters, while having a high level of simplicity and robustness, are known to have poor efficiency at high step-up regime. More complicated topologies have been extensively explored to increase the step-up ratio while keeping a high-e ...

2020

New Insights on Output Capacitance Losses in Wide-Band-Gap Transistors

Elison de Nazareth Matioli, Armin Jafari, Mohammad Samizadeh Nikooytabalvandani, Palliyage Srilak Nirmana Perera

The low ON-resistance of wide-band-gap (WBG) transistors is a key feature for efficient power converters, however, the anomalous loss in their output capacitance (COSS) severely limits their performance at high switching frequencies. Characterizing COSS-lo ...

2019

Comparison of Wide-band-gap Technologies for Soft-Switching Losses at High Frequencies

Elison de Nazareth Matioli, Armin Jafari, Mohammad Samizadeh Nikooytabalvandani, Palliyage Srilak Nirmana Perera, Reza Soleiman Zadeh Ardebili, Halil Kerim Yildirim

Soft-switching power converters based on wide-band-gap (WBG) transistors offer superior efficiency and power density advantages. However, at high frequencies, loss behavior varies significantly between different WBG technologies. This includes losses relat ...

2020

Enhanced DAB for Efficiency Preservation using Adjustable-Tap High-Frequency Transformer

Elison de Nazareth Matioli, Armin Jafari, Mohammad Samizadeh Nikooytabalvandani

Efficient DC-DC power-conversion with wide-span voltage-regulation is crucial to a sustainable and robust power electronics system. Dual-active-bridge (DAB) offers straight-forward regulation and its transformer enables voltage step-up/down required for ma ...

2019

Negative Resistance in Cascode Transistors

Elison de Nazareth Matioli, Armin Jafari, Mohammad Samizadeh Nikooytabalvandani, Palliyage Srilak Nirmana Perera

Cascode topology which includes a high-voltage GaN and a low-voltage Si transistor is an attractive device concept, which uses the low ON-resistance of GaN while still being compatible with Si gate drivers. It demonstrates the highest threshold voltage amo ...

2020

Measurement of WBG-based power supplies

Elison de Nazareth Matioli, Armin Jafari, Hongkeng Zhu

This paper discusses different measurement methods to evaluate the efficiency of WBG-based power supply solutions, including electrical measurement methods and their verification with calorimetric methods, and compares the performance of Si-based and GaN-b ...

IEEE2023

GaN Transistors for Miniaturized Pulsed-Power Sources

Elison de Nazareth Matioli, Armin Jafari

2019

High Step-Up High-Frequency Zero-Voltage Switched GaN-Based Single-Stage Isolated DC-DC Converter for PV Integration and Future DC Grids

Elison de Nazareth Matioli, Armin Jafari

2018