铜转子三相异步电动机温度场流场耦合分析

研发了一台应用在石油顶驱钻井设备的强迫风冷铜转子三相异步电机,首创了无机座设计、定子铁心轭部开通风孔、定子绕组端部环氧树脂密封、采用焊接铜条鼠笼转子等关键技术,满足了电机在频繁起停、过载、盐雾等工况下,对电机温升的苛刻要求。建立了温度场流场流固耦合模型,分析了电机额定负载工况下的各零件稳态温度分布以及瞬态温度随时间变化趋势。仿真计算和温升试验结果表明,沿电机的轴线方向,中后段位置温度较高,没有局部过热点。试验验证了建立的温度场流场耦合模型和仿真结果的合理性,温升满足电机H级要求。在耦合模型的基础上,分析了风道入口压力和定子铁心通风孔径变化对电机温升的影响,为改进电机冷却结构提供理论基础。

TemperatureFluid Field Coupling Analysis of Three PhaseAsynchronous Motor with Copper Rotor

A special three phase asynchronous motor applied to top drive facility was studied, which uses the compulsorily ventilation and nonstandard design. Critical techniques, such as nonbase design, ventilation hole of stator iron yoke, epoxy resin sealing at stator winding end, and squirrelcage rotor composed of copper bars were adopted, which satisfy the strict requirements under the condition of frequent start and stop, overloading, and saltmist. Temperaturefluid field coupling model was established, and then the transientstate temperature trends and steadystate temperature distribution of the parts of motor under the rating condition were analyzed. The results of simulation and thermal rising test showed that the temperature in the axial direction was higher at the locations of the posterior segment, and testify that the temperature distribution has no local hot spot. At the same time, experiment verifies that the temperaturefluid field coupling model and result are reasonable, which satisfy the requirement of H level temperature rise. The effect of inlet pressure and ventilation hole diameter change on temperature rise were analyzed on the basis of coupling model, which provides the theoretic foundation for improving cooling structure of motor.