Study on two different charging methods for superconducting coils in persistent current mode

•Experimental platforms for two kinds of charging methods are demonstrated.•Charging performance on different types of loads is analyzed.•The results show that charging NI HTS coil is much slower than charging INS HTS coil. How to charge high-temperature superconducting coils is a crucial problem for superconducting magnets. In recent years, flux pump is recommended as a promising method for current compensation since it can charge coils without electrical contact to current source. In this work, two types of charging methods, rotating magnet based flux pump and magnetically controlled persistent current switch, are discussed experimentally and numerically. Their output characteristics were tested and demonstrated. Charging performance on different types of loads including insulated HTS coil, no-insulation HTS coil and DC current source, is analyzed and compared. Results of this paper will prove the validity of those two charging methods in future superconducting magnet applications.