Abstract
A model coil for superconducting magnetic energy storage (SMES model coil) has been developed to establish the component technologies needed for a small-scale 100kWh SMES device. The SMES model coil was fabricated, and then performance tests were carried out in 1996. The coil was successfully charged up to around 30kA and down to zero at the same ramp rate of magnetic field experienced in a 100kWh SMES device. AC loss in the coil was measured by an enthalpy method as parameters of ramp rate and flat top current. The results were evaluated by an analysis and compared with short-sample test results. The measured hysteresis loss is in good agreement with that estimated from the short-sample results. It was found that the coupling loss of the coil consists of two major coupling time constants. One is a short time constant of about 200ms, which is in agreement with the test results of a short real conductor. The other is a long time constant of about 30s, which could not be expected from the short sample test results.
