永磁涡流耦合器过载特性的研究

Study on Overload Characteristics of Permanent Magnet Eddy Current Coupler

根据电磁学与传热学理论,对永磁涡流耦合器2类不同的过载情况进行了理论分析与有限元计算,结果表明,小气隙情况下(3 mm-1 000 r/min)的铜转子整体涡流密度值是大气隙情况(15 mm-1 000 r/min)约2.5倍,涡流损耗值分别稳定在1 168 W与204 W左右,小气隙过载情况下,永磁体温度将突破永磁材料最高使用温度,会引发严重的退磁现象,应对其工作状态采取温度在线监控;大气隙过载情况下,由于涡流损耗的降低与热交换环境的改善,永磁体的温度仍处于安全范围内,可以实现过载保护作用,研究结果可为永磁涡流耦合器的工况使用与设计改进提供借鉴。

According to the electromagnetic and heat transfer theory, two different overload situations ofthe permanent magnet eddy current coupler have carried on the theoretical analysis and finite elementcalculation, the results show that the small gap cases （3 mm-1 000 r/min） of the copper rotor＇s eddycurrent density value is the large gap （15 ram-1 000 r/rain） about 2.5 times, the eddy current loss isabout 1 168 W and 204 W. Small air gap overload, the permanent magnet temperature will breakthrough the maximum use of permanent magnet material temperature, will lead to a seriousdemagnetization phenomenon, and it needs to take temperature online monitoring of its working state.Large air gap overload, because of the low eddy current loss and the improvement of thermalenvironment, the temperature of the permanent magnet is still in the safe range, then can achieveoverload protection function, the results can be used for the design of the permanent magnet eddycurrent coupler.