The Application of Superconducting Technologies in Future Electrical Power Systems

Abstract

Growing power demand in countries such as the UK can often result in increased power losses and voltage control problems within distribution networks. Mitigation of these issues in distribution networks is challenging when conventional power conductors and transformers are considered. There are several methods that may reduce losses in distribution networks, such as carefully sited and operated distributed generation (DG) and distributed control techniques. Since High Temperature Superconductor (HTS) cables exhibit zero resistance when cooled to the boiling point of liquid nitrogen (77Keliven), they have the potential to be used to address these issues in distribution networks. This thesis has investigated the impact of HTS cables and HTS transformers on power losses, voltage changes, fault levels and DG on an existing section of the UK distribution network and compares this with one utilising conventional cables and lines. This study has been accomplished using IPSA. Also, another piece of work calculates in terms of the power losses in HTS cables and HTS transformers including the power needs of their refrigeration systems. This has then been compared these to power losses incurred in conventional distribution and transmission networks.
Furthermore, the thesis introduces the comparison costs of HTS cables and HTS transformers with conventional cables and transformers and considers future projected costs for HTS cables and transformers. This information has been used to enable a techno economic evaluation of the potential of future alternative superconductor network design.
A method for reactive power sharing in an AC superconductor distribution network, including various DGs, has also been proposal. In addition, this thesis has demonstrated the possibility of increasing the ability of electrical distribution networks to deliver high power densities to critical urban areas, whilst avoiding the need for heavy network reinforcement and additional assets. These studies en achieves using IPSA and Matlab software.
Finally, research of work was carried out to investigate the practical effects of installing superconductor equipment and identify novel network designs that make the best use of the attributes of superconducting network assets in terms of lower power losses, lower capital cost and a lower risk level than existing conventional distribution network designs.
In 2013, the total cost of the future 33kV superconductor distribution network design would be £842.1M higher than that of the present conventional distribution network design. However, by 2030 the future 33kV superconductor network design will be £16.86 M lower than the present conventional network design. Consequently, these results show that using HTS assets in large distribution network design, operating at different voltage levels could save millions of pounds in the future.