研究自然冷却的无槽管状永磁直线电机(tubular permanent magnet linear actuator,TPMLA)的机械气隙长度,通过约束和引导热量的流通路径来使永磁体的温度达到最低。通常无槽绕组产生的热量必须首先通过周围的空气进行传导,其散热条件比...研究自然冷却的无槽管状永磁直线电机(tubular permanent magnet linear actuator,TPMLA)的机械气隙长度,通过约束和引导热量的流通路径来使永磁体的温度达到最低。通常无槽绕组产生的热量必须首先通过周围的空气进行传导,其散热条件比有槽电机更加恶劣。虽然较小的机械气隙可以增强气隙磁密,但是绕组产生的大部分热量将会传到永磁体上,导致永磁体温升,并减小其剩磁,使永磁体有失磁风险。因此,合理的机械气隙长度对于无槽管状永磁直线电机极其重要。建立电机的电磁和热模型,并将结果与有限元方法进行比较。制作3台不同机械气隙的样机,并进行实验。结果表明,机械气隙对限制和引导热流具有重要的作用,通过增加机械气隙长度来降低永磁体温度的方法取得了良好的效果。展开更多
The workpieces of A357 alloy were routinely heat treated to the T6 state in order to gain an adequate mechanical property.The mechanical properties of these workpieces depend mainly on solid-solution temperature,solid...The workpieces of A357 alloy were routinely heat treated to the T6 state in order to gain an adequate mechanical property.The mechanical properties of these workpieces depend mainly on solid-solution temperature,solid-solution time,artificial aging temperature and artificial aging time.An artificial neural network（ANN） model with a back-propagation（BP） algorithm was used to predict mechanical properties of A357 alloy,and the effects of heat treatment processes on mechanical behavior of this alloy were studied.The results show that this BP model is able to predict the mechanical properties with a high accuracy.This model was used to reflect the influence of heat treatments on the mechanical properties of A357 alloy.Isograms of ultimate tensile strength and elongation were drawn in the same picture,which are very helpful to understand the relationship among aging parameters,ultimate tensile strength and elongation.展开更多
文摘研究自然冷却的无槽管状永磁直线电机(tubular permanent magnet linear actuator,TPMLA)的机械气隙长度,通过约束和引导热量的流通路径来使永磁体的温度达到最低。通常无槽绕组产生的热量必须首先通过周围的空气进行传导,其散热条件比有槽电机更加恶劣。虽然较小的机械气隙可以增强气隙磁密,但是绕组产生的大部分热量将会传到永磁体上,导致永磁体温升,并减小其剩磁,使永磁体有失磁风险。因此,合理的机械气隙长度对于无槽管状永磁直线电机极其重要。建立电机的电磁和热模型,并将结果与有限元方法进行比较。制作3台不同机械气隙的样机,并进行实验。结果表明,机械气隙对限制和引导热流具有重要的作用,通过增加机械气隙长度来降低永磁体温度的方法取得了良好的效果。
文摘The workpieces of A357 alloy were routinely heat treated to the T6 state in order to gain an adequate mechanical property.The mechanical properties of these workpieces depend mainly on solid-solution temperature,solid-solution time,artificial aging temperature and artificial aging time.An artificial neural network（ANN） model with a back-propagation（BP） algorithm was used to predict mechanical properties of A357 alloy,and the effects of heat treatment processes on mechanical behavior of this alloy were studied.The results show that this BP model is able to predict the mechanical properties with a high accuracy.This model was used to reflect the influence of heat treatments on the mechanical properties of A357 alloy.Isograms of ultimate tensile strength and elongation were drawn in the same picture,which are very helpful to understand the relationship among aging parameters,ultimate tensile strength and elongation.
