基于分层等效模型的高速电机交流损耗影响分析

Analysis on AC loss of high-speed machine based on layered equivalent model

为了准确计算槽内随机排布绕组的高频损耗,提出基于分层等效替换的随机分布绕组交流损耗解析模型,推导出单层和双层绕组的交流损耗,并与有限元模型进行对比,分析了不同线径下的交流损耗变化规律。由于交流损耗对导线位置非常敏感,分析了绕组排布方式和绕组连接方式对高频交流损耗的影响规律。结果表明,当频率小于3 kHz时,槽口磁密变化为交流损耗的主要影响因素;当频率大于3 kHz时,集肤效应和临近效应影响更显著。同时端部连接方式采用平移换位和对称换位均能有效降低交流损耗,削弱效果分别为42.6%和53.4%。最后,通过对比不同电流频率下的磁芯线圈实验与模型结果,解析模型和有限元模型的计算误差分别为3.9%和2.7%,验证了模型计算结果的准确性及影响规律分析的正确性。

In order to accurately calculate the high frequency loss of randomly arranged windings in slots,a single slot analytical model of AC loss of randomly distributed windings based on layered equivalent replacement was proposed,and the AC losses of single layer and double layer windings were deduced.Compared with the finite element model,the variation rule of AC loss under different wire diameters was analyzed.Since the AC loss is sensitive to the wire position,the influence of winding arrangement and winding connection mode on the high frequency AC loss was analyzed.The results show that the change of slot magnetic density is the main influence factor of AC loss when the frequency is less than 3 kHz,and the skin effect and proximity effect are more significant when the frequency is greater than 3 kHz.At the same time,the translation transposition and symmetrical transposition of the end connection can effectively reduce the AC loss,and the weakening effects are 42.6%and 53.4%,respectively.Finally,by comparing the experimental and model results of the magnetic core coil at different current frequencies,the calculation errors of the analytical model and the finite element model are 3.9%and 2.7%respectively,which verifies accuracy of the model calculation results and indirectly verifies correctness of the in-fluence law analysis.