MVDC-ERS will produce 2 PhD students to research flexible medium voltage DC railway electrification systems, one in the UK and one in Romania. In addition to delivering the technical/research components of S2R-OC-IPX-03-2018: Innovative/breakthrough mobility concepts (with rail as backbone), this proposal will also support the training of two early stage researchers, to build the research capacity within the rail sector across Europe.
Railway electrification provides faster and reliable train journeys compared to those of diesel trains and a strong reduction of pollution in busy stations and the country-side. However, many national programmes for the electrification of new and existing railway lines have required a substantial investment for the railway infrastructure. This is because railway electrification uses AC single-phase power that requires connection to high-voltage transmission lines, which are not always available in the intended places where the railway feeder stations should be located and usually require complicated and extremely expensive modifications of the existing layouts, i.e. tap and looped connections of the substations. Additionally, new electric railways are not seen favourably by the transmission operators as they introduce intermittent load peaks that affect the stability of the system, especially for future scenarios where the inertia of the power system will be substantially reduced for the widespread adoption of renewable power sources.
The overall aim of MVDC-ERS is to investigate the next generation railway electrification systems, DC power electronic traction transformers and technologies for integrating renewable sources, to challenge the traditional rail approach to develop innovative and breakthrough technological concepts.
The MVDC-ERS project will produce ground breaking knowledge on the next generation of railway power supplies and on-board traction systems to propel electric rail transport into the era of distributed generation, in line with the EU roadmap for deployment of new green transport technologies in Europe and worldwide. This project has the following main research objectives:
- to introduce new high-efficiency topologies of power conversion systems to convert medium-voltage AC power into medium-voltage DC power with the capability of limiting the short-circuit current;
- to introduce high-power density topologies of power converters for on-board DC transformers;
- to investigate the impact of the forthcoming wide band-gap semiconductor devices in terms of efficiency and voltage level for the converters of the feeder stations and in terms of weight and volume for the traction converters;
- to understand how the new railway electrification system should be controlled and protected when renewable power sources are integrated;
- to understand how on-board energy storage can be exploited and how it can optimise the operations of the network;
- to work with industrial stakeholders to investigate the marketability of the new electrification system and trains.
The training objectives of the proposal are:
- to train the two early-stage researchers on undertaking challenging research projects under the guidance of leading senior scientists;
- to offer a comprehensive formative experience to the early-stage researchers with technical workshops and conferences;
- to enhance mobility of the early-stage researchers across the academic institutions of the consortium;
- to stimulate networking of researchers and a multi-disciplinary approach to address the challenges of medium voltage DC railways.