A Kilo-Amp Linear-Motor Type Flux Pump

Abstract

A kilo-amp linear-motor type flux pump with the maximum output DC current exceeding 1610 A had been designed and manufactured. We had optimized the large-current flux pump based from the previous design, and shortened the travelling wavelength of the flux pump, and simulated its magnetic density distribution with COMSOL Multiphysics, and obtained the present design parameters after analysis. We had placed 12 superconducting single loops side by side in the air gaps on both sides of the flux pump, and had used the flux pump to charge them. We had applied different magnetic flux density in the air gap, the maximum DC output current of the flux pump was measured at 1619 A in the liquid nitrogen at 77 K. We have carried out theoretical analysis on the direction of the pumped current on both sides of the flux pump, while had changed the polarities of the DC windings to make sure that the current directions on both sides are the same. Comparing with the traditional superconducting power supply of the same output current level, this flux pump had not only eliminated the current leads, but also reduces the cost, size and energy consumption of the power source by at least one order. Finally, we designed the prototype of the kilo-amp linear-motor type flux pump to measure the critical current of the superconducting cables.