驱动风机电动机温度场非均布热源耦合研究

Research on Temperature Field Non-uniformly Distributive Heat Source Coupled Investigation of Ventilator-driving Motor

风机驱动电动机由于工作环境和频繁启停的工作要求,常由变频器控制,其运行中谐波含量大,发热严重。为研究其温升分布规律,以一台4 500 k W电动机为例,基于电磁学及传热学理论,建立三维半域通风冷却物理模型。应用有限元法,对额定工况下电动机内电磁场进行仿真计算,把非均布的损耗分布以热源形式映射到温度场中,通过电磁场与温度场双向耦合,准确计算电动机各部分的温升分布。此外,为更具对比性,对同种工况下体积均布热源的方法进行仿真计算,通过与试验结果的对比分析,验证双向耦合的方法较均布热源的方法更接近真实值,表明双向耦合的方法更具科学性。

The problems of harmonics and the heat of ventilator-driving induction motor（VDIM） are quite large when operating under the frequency conversion control system. The cooling structure of VDIM is usually complex. In order to investigate the rule of the temperature distribution of VDIM, 4 500 kW motor is taken as an investigated example. Based on the electromagnetic theory and heat transfer theory, a three dimensional of ventilation-cooling physical model is built to simulate the electromagnetic field in the motor under rated operating condition using the finite-element volume method, non-uniformly distributive loss （NDL） is mapped to the temperature field in the type of heat source, and by bi-direction coupling between electromagnetic field and temperature field, Calculating the distribution regularity of parts exactly. Besides in order to compare clearly, the same operation conditions are simulated using homogeneous distribution volume heat sources （HDVHS）. By comparing with the test result of VDIM, the result of NDL is much more approach to the true data than HDVHS, which indicate that the method of Bi-direction coupling is more scientific.