The development and manufacturing of HTS armature windings for 200 kW motor

For the last 5 years the number of projects in electrical motor design has significantly increased. Currently, one of the most breakthrough technologies in this area is the use of superconducting materials to increase the power-to-weight ratio of motors. HTS materials can be used in AC windings of motors, but should be optimized on a case-by-case basis to minimize AC losses. There are different approaches to minimize AC losses in HTS coils. In this work, to decrease AC losses we used parallel HTS tapes and stacked (face-to-face) HTS tapes.

We have calculated and developed two approaches of fully insulated superconducting coils for AC stator windings to compare coils made from stacked HTS tape and copper covered HTS tape. 4 double pancake coils with different number of parallel tapes were manufactured: two with insulated HTS tape and another two coils with insulated stacked HTS tape. We measured the critical current of these coils (77K, self-field) and also AC losses for a wide range of currents and frequencies. All the results were compared with FEM/FEA calculations.

We chose the HTS coil design which has minimum AC losses for the production of HTS armature windings. All the connections between coils were made with superconducting low resistivity joints. HTS stator coils were connected to the current leads and tested in a cryostat.