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Abstract—As a marvelous promotion of applications with HTS magnet in a variety of fields appears, it is of particular importance to compensate persistent current decay in HTS magnets. Therefore, a large quantity of means of contactless power supply (CPT) have emerged in endlessly. In general, CPT mainly consists of 5 parts, which include power, inverter circuit, electromagnetic inductive coupler, rectifier circuit and load. A pretty large proportion of attention has been paid to optimize circuit topology and coupler structure rather than rectifier circuit. According to the majority of proposed methods which utilized diodes as rectifier, the inevitable heat loss resulted from operating diodes is always puzzled. For that reason, this paper presented a novel means, taking the place of diodes with a YBCO-coated conductor bridge which coordinated with a specific programed AC power signal aiming at AC-DC conversion, to decrease unavoidable heat loss from normal diodes rectifier circuit. Once an alternative current where positive peak value is higher than negative peak value is induced in the superconducting secondary winding, it drives the bridge into flux flow region and induces direct voltage between the bridge at around its positive peak value. In consequence, power supply for HTS magnets was accomplished. Apart from that, due to the particularity of this experiment, in which rectifier circuit connected with both secondary coils wound with YBCO-coated conductor and magnet is in the cooling system(77K). So that diodes rectifier has to operate in 77K environment and endures unignorable effect. However, regardless of that defect, the cooling system is coincidently and perfectly suitable for a YBCO-coated conductor bridge. In a word, considering of the whole power supply system, utilizing the bridge is able to reduce heat loss in view of zero resistance. Futhermore, this means also converts the shortcoming towards diodes rectifier circuit in the cryogenic environment into superiority of the bridge.
Index Terms—HTS magnet, contactless power supply(CPT), YBCO-coated conductor bridge
