Ac loss modelling and measurement of superconducting transformers with coated-conductor Roebel-cable in low-voltage winding
- 12 October 2015
- journal article
- research article
- Published by IOP Publishing in Superconductor Science and Technology
- Vol. 28 (11), 114008
- https://doi.org/10.1088/0953-2048/28/11/114008
Abstract
Power transformers using a high temperature superconductor (HTS) ReBCO coated conductor and liquid nitrogen dielectric have many potential advantages over conventional transformers. The ac loss in the windings complicates the cryogenics and reduces the efficiency, and hence it needs to be predicted in its design, usually by numerical calculations. This article presents detailed modelling of superconducting transformers with Roebel cable in the low-voltage (LV) winding and a high-voltage (HV) winding with more than 1000 turns. First, we model a 1 MVA 11 kV/415 V 3-phase transformer. The Roebel cable solenoid forming the LV winding is also analyzed as a stand-alone coil. Agreement between calculations and experiments of the 1 MVA transformer supports the model validity for a larger tentative 40 MVA 110 kV/11 kV 3-phase transformer design. We found that the ac loss in each winding is much lower when it is inserted in the transformer than as a stand-alone coil. The ac loss in the 1 and 40 MVA transformers is dominated by the LV and HV windings, respectively. Finally, the ratio of total loss over rated power of the 40 MVA transformer is reduced below 40% of that of the 1 MVA transformer. In conclusion, the modelling tool in this work can reliably predict the ac loss in real power applications.Funding Information
- New Zealand Ministry of Business, Innovation and Employment: (C08X1301)
This publication has 32 references indexed in Scilit:
- High-temperature superconducting (HTS) transformers for power grid applicationsPublished by Elsevier BV ,2015
- Progress in Production and Performance of Second Generation (2G) HTS Wire for Practical ApplicationsIEEE Transactions on Applied Superconductivity, 2014
- Coated conductors for power applications: materials challengesSuperconductor Science and Technology, 2014
- Computation of Losses in HTS Under the Action of Varying Magnetic Fields and CurrentsIEEE Transactions on Applied Superconductivity, 2013
- Computing AC losses in stacks of high-temperature superconducting tapesSuperconductor Science and Technology, 2011
- An improved FEM model for computing transport AC loss in coils made of RABiTS YBCO coated conductors for electric machinesSuperconductor Science and Technology, 2011
- Towards Faster FEM Simulation of Thin Film Superconductors: A Multiscale ApproachIEEE Transactions on Applied Superconductivity, 2010
- Overview of superconductivity in Japan – Strategy road map and R&D statusPhysica C: Superconductivity and its Applications, 2008
- Modeling of coated conductor pancake coils with a large number of turnsSuperconductor Science and Technology, 2008
- Measuring transport AC losses in YBCO-coated conductor coilsSuperconductor Science and Technology, 2007