Phd Majed Eddine MOUSTAID “Experimental development of a thermosiphon loop for thermal regulation of power electronic devices”

2020-01-16T16:25:42+01:00January 16th, 2020|Phd, Power Electronics & Converters|

The work of this thesis focuses on the experimental development of a passive and biphasic cooling system to cool down power electronics. Some of those modules are mean voltage power converters developed by Supergrid Institute. Some constraints have been imposed upstream to this project. While some limitations are of the technological nature, other constraints are related mainly to the environmental and biological aspects. The first part of this thesis was to find a suitable cooling system that could be adapted to the project specifications. After some research, we decided to build a loop thermosiphon filled with NOVEC 649.

SuperGrid Institute has achieved a major milestone in the development of 10 kV Silicon Carbide (SiC) devices

2020-01-09T09:07:49+01:00January 9th, 2020|Power Electronics & Converters|

SuperGrid Institute has achieved a major milestone in the development of 10 kV Silicon Carbide (SiC) devices such as 5A BJT and 50A PIN diode as part of its work on developing innovative solutions for MV converters. Recent tests revealed outstanding switching performances.

Phd Juan PAEZ “HVDC Converters for the interconnection of HVDC grids”

2019-12-13T15:15:25+01:00December 13th, 2019|Phd, Power Electronics & Converters|

In order to include large-scale renewable sources into the electrical system and to transport high amounts of energy through long distances, the actual AC grid must be upgraded. HVDC transmission grids appear as a promising solution to upgrade the system and answer correctly the future needs and requirements. The development of such grids can be done following two different approaches. For one side, a DC system designed totally from zero following a standardization of HVDC technology, and for the other side, an incremental evolution using the existing HVDC lines. The second approach seems more reasonable due to the reutilization of infrastructure, the inconvenient is that the technology used on each existing line is different. Thus, their interconnection will require DC¬DC converters as interface elements. These structures allow the interconnection of different HVDC schemes and offer more functionalities than only DC voltage adaptation like power flow control and protection.

NPC assessment in insulated DC/DC converter topologies using SiC MOSFETs for Power Electronic Traction Transformer

2019-10-22T11:34:14+02:00October 24th, 2019|Power Electronics & Converters, Publications|

Power electronic traction transformers (PETT) are multilevel AC/DC on-board converters, studied for railway applications to replace traditional solution with low frequency transformers. This paper focuses on the insulated DC/DC converter in a PETT. Three variants of resonant single active bridges (R-SAB) with 3-level NPC primaries are optimised to maximise the efficiency, under mass and dimension constraints. They are sized and compared for a 2 MW PETT on a 15 kV/16.7 Hz railway infrastructure, using 3.3 kV SiC MOSFETs and nanocrystalline C-core transformers with cast resin insulation and forced air cooling. The highest efficiency at nominal power, 99.17 %, is reached for a configuration with a 3-level full bridge NPC primary, a 2-level full bridge secondary, and a 32.1 L/49.1 kg transformer operating at 6 kHz.

3-phase medium frequency transformer for a 100kW 1.2kV 20kHz Dual Active Bridge converter

2019-10-15T15:13:19+02:00October 15th, 2019|Power Electronics & Converters, Publications|

The article presents a three-phase Medium Frequency Transformer being a part of a 100kW 1.2kV 20kHz Dual Active Bridge DC-DC converter. The transformer design is detailed focusing on winding and core power loss calculation. The high power three-phase MFT prototype is presented. The experimental results include the transformer impedance characteristics, no load test and three-phase DAB full load test waveforms.

Cost-performance framework for the assessment of Modular Multilevel Converter in HVDC transmission applications

2019-10-15T15:10:51+02:00October 15th, 2019|Power Electronics & Converters, Publications|

This article proposes a methodology of Cost-Performance Assessment (CPA) enabling the efficient cost evaluation required for the Cost-Benefit Analysis (CBA). The proposed method is applied for the Modular Multilevel Converter (MMC) in offshore wind high voltage direct current (HVDC) transmission. Thanks to the developed model, an analysis of submodule voltage rating is performed demonstrating the interest of this methodology in the evaluation of new technologies for HVDC transmission. The analysis shows that increasing the submodule (SM) voltage could lead to savings in the MMC cost and weight.

Requirements for interconnection of HVDC links with DC-DC converters

2019-10-15T14:54:37+02:00October 15th, 2019|Power Electronics & Converters, Publications|

The number of high voltage direct current (HVDC) links continue to increase over the years, most of them, for offshore applications or bulk power transmission over long distances. The present paper evaluates the possible development of a direct current (dc) grid in Europe given the present, and future, HVDC links. Eight potential cases for the interconnection between close links are suggested as starting scenario for a multiterminal network. The need of a dc-dc converter and its special requirements are evaluated in function of suggested interconnections. As an example, a case study is chosen to evaluate the behavior of an interconnection between line commutated converter (LCC) and voltage source converter (VSC) link using a front-to-front (F2F) isolated converter.

Assessment of the Impact of Split Storage within Modular Multilevel Converter

2019-10-15T14:46:55+02:00October 15th, 2019|Power Electronics & Converters, Publications|

This paper deals with the opportunities to introduce split storage into an MMC. The analysis is focused on the internal energy exchange to maintain the proper function of the converter by using circulating current. Analysis shows that, SM capacitor voltage ripple or semiconductors load are greatly influenced by additional circulating current injection. This study helps to design Embedded ESSs in the converter to provide new function like ancillary services for power system operation. Finally, a simulation of an MMC with ESS confirms analytical calculations.

Interest of using a micro-meter spatial resolution to study SiC semi-conductor devices by Optical Beam Induced Current (OBIC)

2019-09-30T11:44:23+02:00September 30th, 2019|Power Electronics & Converters, Publications|

In this paper we present a new test bench called micro-OBIC used to characterized wide band gap semi-conductor. Micro-OBIC allows to scan an Optical Beam Induced Current (OBIC) signal with a microscopic spatial resolution. We used micro-OBIC to characterize peripheral protection such as MESA, JTE or JTE in high voltage SiC device.