High Current Module and Technologies Optimised for HVDC

The proposed research will investigate the role that advanced power semiconductor module design can play in improving the efficiency and increasing the capacity of Voltage Source, HVDC converters.

Growing use of HVDC for integration of renewable energy sources and transnational electricity transmission is driving development HVDC technologies. Within Europe there are over 20 HVDC schemes currently planned and under construction most of which will employ new IGBT based Voltage Source Converter (VSC) technology. The development of new multi-level converters greatly raised DC operating voltages in VSC converters and improved their performance.

Despite these significant advances, there are still strong drivers to raise both capacity and efficiency. To date multi-level HVDC typically utilises high voltage power semiconductor modules originally designed for other applications. At projected deployment rates, VSC-HVDC is likely to become one of the key markets for high voltage power. The size of this potential market justifies the development of a new power semiconductor switch, specifically designed around the needs of multi-level VSC converters. Such a power switch will be a composite of high capacity multi-device module and an associated intelligent gate drive which can optimise module performance in multi-level VSC systems. It is proposed that such techniques can provide significant gains in both converter capacities and efficiency at a reduced cost.

I. Academic Impact
This EPSRC Project brings together two of the UK's leading research institutions in the area of Power Semiconductor devices and adds one of the UK's leading research teams in the area of power electronic applications particularly in the power systems environment. The academic team is supported by one of the worlds leading suppliers of HVDC projects and a world leading semiconductor device manufacturer in the area of high power semiconductors and an original start up which is rapidly becoming a partner of choice in power semiconductor gate drives. The support of the companies allows the academic team to progress more quickly by adding world class engineering effort to what is undoubtedly a serious scientific project. The project is directly aimed at accelerating the development of cost effective HVDC Transmission schemes. By addressing the science of the main active component, it's capacity can be increased to a level whereby such schemes are the required power , the efficiency increased, the robustness to faults improved and the cost reduced. The mutual understanding between the industry partners and the academic teams also brings a new perspective and a mix of expertise such that the challenges being addressed could not be seriously attempted by any one of the partners. The rapidly expanding nature of this field also demands an expanded pool of talented researchers and the professional and academic development of the Post Doctoral Research Assistants is seen as a significant contribution to the skills shortage in this area [1]. The wider direct academic impact will be in publications and patents and a plan and draft agreement exists to facilitate this. To aid the project and widen the impact academic, guest participation in meetings is planned. It is also anticipated that this project will reveal technical pathways which can be addressed in the proposed TSB HVDC program (see details of this call) . It is also anticipated that results here will help provide pathways to impact for the non application specific projects funded by the EPSRC Underpinning Power Electronics 2012 program [2]
I. Economic Impact
The UK economy needs to replace ageing generation equipment and the national will is to provide a significant amount of power through wind generation to make the economy independent of fluctuating energy prices [3]. On shore Wind power has been identified by the uk government as "one of the most cost-effective and proven renewable energy technologies" [4]. Yet many of the best locations remain remote. This project is aimed at advancing HVDC technology so that HVDC schemes can deliver the renewable power at a high power level, with improved cost effectiveness through lower component costs, higher efficiency and an improved robustness to temporary faults such that the system does not trip out leaving manufacturers and domestic consumers without power. All of these factors influence the adoption of such a scheme and ultimately energy prices in the long term. There is a clear route to economic impact via the partner companies including Amantys, a UK start-up company using aspects of earlier EPSRC funded research.
I. Societal Impact
This research will contribute to climate change mitigation by facilitating expansion of HVDC schemes and the integration of clean generation particularly wind farms. By facilitating HVDC deployment, this research will help to meet the desire for wind farms to be remotely located on shore and offshore and reduce CO2 emissions (REF). A further expansion of HVDC will facilitate the delivery of large amounts of electric power to major cities for us in use in personal transport whilst reducing oil dependence and CO2 emissions (electric cars and vans will consume half the UK's Electricity by 2050) [4]. Future developments in the European Super grid will allow Geothermal, Hydro and Solar power to be delivered to the UK and Western Europe from the source locations.