In order to further optimize the size of the linear-motor type flux pump, an updated linear-motor type motor flux pump device with single side DC winding was designed and fabricated. Compared with the previous generation of linear-motor type flux pump with traveling wave length of 21 mm, the volume of this generation of linear-motor type flux pump with traveling wave length of 15 mm is reduced by nearly 30% and the pumping current capacity is increased by more than 30%, which generated the same DC biased AC travelling magnetic wave in the airgap, and pumped DC current into the high temperature superconducting (HTS) closed-loop in a non-contacting manner, based on the macroscopic magnetic coupling effect. In this work, we tested the performances of this updated flux pump device. We pumped current into two parallel superconducting stators and a YBCO double pancake coils. The pumping current of two parallel superconducting stators reached 219 A, while pumped current in YBCO double cake coil (DPC) reached 73 A, mainly due to the limit of the small critical current of the HTS DPC. The experimental results show that using one-sided DC coil can achieve effective bias effect, which further verified the rationality of explanation based on the macroscopic magnetic coupling effect. These results are helpful to optimize the HTS flux pump device and further understand the working mechanism of the flux pump.
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