非晶合金高速永磁电机铁耗与温升研究

发布时间：2018-10-08 15:31

【摘要】：高速永磁电机集高效率,高功率密度,可直接驱动高速负载等优点于一身,广泛应用于电动汽车、高速电主轴、航空发航天和微型燃气轮发电等领域。但是高速永磁电机的单位损耗大、散热面积小、电机散热困难、易于引发转子过热,严重时甚至可能导致永磁体不可逆失磁,不利于电机的可靠运行,所以对高速永磁电机损耗与温升进行研究是十分必要的。由于铁耗在高速电机中占比重很高,因此,本文采用具有低损耗的非晶合金作为高速电机定子铁心材料。研究高速非晶合金永磁电机铁耗与温升,对影响铁耗与温升的诸多因素进行了研究并通过试验加以验证。首先,通过实验测得了不同频率下非晶合金定子铁心的损耗曲线。然后,基于有限元软件对正弦波供电时电机的空载铁耗进行计算,分别研究了频率、转子磁极结构、极槽配合这些因素的改变对空载铁耗的大小及其分布的影响。得到了电机频率与空载铁耗的拟合关系,随后计算了在变频器供电下的空载铁耗分布规律,并对非晶合金高速永磁电机样机在变频器供电下进行了的空载铁耗试验,验证计算结果的准确性。其次,基于流固耦合方法研究了高速永磁电机绕组端部等效与绕组灌封对电机温升的影响,并研究了采用不同导热系数导热胶灌封对电机温升的影响。计算了转子表面粗糙度、电机转速、定子内表面有无槽口对电机定转子传热的影响。得到了电机转子表面粗糙度、电机转速与空气摩擦损耗的拟合关系。并研究了冷却边界条件入口水速、水温对电机温升的影响。最后,采用有限体积法对高速永磁电机机壳水冷全封闭式高速永磁电机在不同转子结构下机内流体场与温度场的耦合场进行仿真,研究不同转子结构对对电机转子散热的影响规律,通过在转子铁心开设轴向通风孔并在转子端面加入风刺的方法来加强电机内空气的湍流效应,以改善端腔的散热条件,并研究了不同转子孔数量与转子孔尺寸对电机流体场与温度场的影响,该永磁体温升抑制措施可以为结构型式相近的全封闭高速永磁电机提供参考。并对文中研究的15kW全封闭水冷高速非晶合金永磁电机的样机进行温升试验,通过对比计算结果与试验值验证了温升计算结果的正确性。
[Abstract]:High speed permanent magnet motor has the advantages of high efficiency, high power density, direct driving high speed load and so on. It is widely used in electric vehicles, high speed motorized spindle, aerospace and micro gas wheel power generation and so on. However, the unit loss of high speed permanent magnet motor is large, the heat dissipation area is small, the motor is difficult to dissipate heat, it is easy to cause rotor overheating, and when serious, it may even lead to irreversible loss of magnetic field of permanent magnet, which is not conducive to the reliable operation of the motor. So it is necessary to study the loss and temperature rise of high speed permanent magnet motor. Due to the high proportion of iron consumption in high speed motor, the amorphous alloy with low loss is used as the stator core material of high speed motor in this paper. The iron consumption and temperature rise of high speed amorphous alloy permanent magnet motor are studied. Many factors affecting iron consumption and temperature rise are studied and verified by experiments. Firstly, the loss curves of amorphous alloy stator core at different frequencies were measured experimentally. Then, based on the finite element software, the no-load iron loss of sinusoidal power supply motor is calculated. The influence of frequency, rotor pole structure and pole slot on the size and distribution of no-load iron loss is studied. The relationship between motor frequency and no-load iron consumption is obtained, and the distribution law of no-load iron consumption under inverter power supply is calculated, and the no-load iron consumption test of amorphous alloy high-speed permanent magnet motor prototype is carried out under inverter power supply. Verify the accuracy of the calculation results. Secondly, based on the fluid-solid coupling method, the effect of winding end equivalence and winding sealing on the temperature rise of high speed permanent magnet motor is studied, and the effect of different thermal conductivity glue on the temperature rise of the motor is studied. The effects of rotor surface roughness, motor speed and stator surface slotted or not on the heat transfer of stator and rotor are calculated. The relationship between rotor surface roughness, motor speed and air friction loss is obtained. The influence of inlet water velocity and water temperature on the temperature rise of motor is studied. Finally, the finite volume method is used to simulate the coupling field of fluid field and temperature field of high-speed permanent magnet motor with water-cooled fully enclosed high-speed permanent magnet motor under different rotor structures. The influence of different rotor structures on the heat dissipation of motor rotor is studied. The air turbulence effect in the motor is strengthened by opening an axial ventilation hole in the rotor core and adding wind spurs to the end of the rotor to improve the heat dissipation conditions of the end cavity. The effects of the number of rotor holes and the size of rotor holes on the fluid field and temperature field of the motor are studied. The temperature rise suppression measures of the permanent magnet can provide a reference for the fully enclosed high speed permanent magnet motor with similar structure. The temperature rise test of the 15kW fully closed water cooled high speed amorphous alloy permanent magnet motor studied in this paper is carried out, and the correctness of the temperature rise calculation is verified by comparing the calculated results with the experimental results.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM351

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