Magnetization Loss of CORC With Various Configurations of 2G HTS Strands

The high temperature superconducting (HTS) conductors for electrical power devices and machines should have large current capacity and low AC loss. Conductors on round core (CORC) is one of the promising conductors that have the characteristics. It consists of helically wound HTS tapes on the round core of copper. We simulated a striated HTS tape of CORC with multiple conductors in parallel. Two HTS tapes with the width of 6 mm emulated a 12 mm tape with one striation and three HTS tapes with the width of 4 mm emulated the one with two striations, and so on. The performance of CORC depends on the diameter of the core former and the pitch of the helical winding. First, we investigated the characteristics of the critical current by the diameters of the core formers and the pitch lengths for 6 mm HTS tapes. And then we measured the magnetization losses of several samples for the emulation of the striation. We also measured the losses of the samples with the 24 mm wide strands. All samples have been made twice for 2 different types. One set had no end-connections. So, the parallel HTS tapes did not connect with each other. The other set had joints at both ends. So, there can be the circulating currents between the parallel tapes. Finally, we rotated all samples during the measurement step by step. We confirmed that the angular position of CORC sample to the magnetic field did not affect the magnetization losses.