﻿ 动力系统永磁同步电动机流体和热场的计算分析
 舰船科学技术  2022, Vol. 44 Issue (20): 116-119    DOI: 10.3404/j.issn.1672-7649.2022.20.023 PDF

1. 福州大学，福建 福州 350000;
2. 龙岩学院，福建 龙岩 364012

Computational analysis of fluid and thermal field of permanent magnet synchronous motor in power system
HONG Tian-xing1,2
1. Fuzhou University, Fuzhou 350000, China;
2. Longyan University, Longyan 364012, China
Abstract: The advent of the Industry 4.0 era has put forward higher requirements for the control efficiency and stability of industrial automation and other industries. Permanent magnet synchronous motor is a key component in AC servo system. It has stable output torque, high efficiency and high reliability. It has been widely used in foundry, industrial control robots, and CNC machine tools. This paper mainly calculates and analyzes the fluid and thermal fields of the permanent magnet synchronous motor, and further understands its characteristics, so as to continuously improve and apply it.
Key words: permanent magnet synchronous motor     fluid     thermal field
0 引　言

1 永磁同步电动机的基本结构

 图 1 永磁交流同步电动机结构图 Fig. 1 Permanent magnet AC synchronous motor structure diagram

 图 2 永磁同步电动机转子结构图 Fig. 2 Permanent magnet synchronous motor rotor structure diagram

2 动力系统永磁同步电动机流体计算分析 2.1 流体传热耦合场数学模型分析

 $\frac{{\partial \rho }}{{\partial t}} + \nabla \cdot \left( {\rho \mathop v \nolimits_r } \right) = 0 \text{，}$ (1)
 $\frac{\partial }{{\partial t}}\left( {\rho v} \right) + \nabla \cdot \left( {\rho \mathop {vv}\nolimits_r } \right) + \rho \left( {\omega \times v} \right) = - \nabla \rho + \nabla \tau + F \text{。}$ (2)

2.2 电动机内流体流动规律的研究

 图 3 电动机冷却器出入口温度误差曲线 Fig. 3 Temperature error curve of motor cooler inlet and outlet
2.3 定子径向通风沟内的空气流速变化

 图 4 定子1-3号径向通风沟速度分布图 Fig. 4 The velocity distribution diagram of stator No. 1-3 radial ventilation channels

 图 5 定子4号和5号径向通风沟速度分布图 Fig. 5 The velocity distribution diagram of the stator No. 4 and No. 5 radial ventilation ditch

5个通风沟中，5号风沟的流速最大，散热的效果也好，但是，因为接近风机的前端，在经过前面的排气管后，空气的温度会迅速升高，所以不会最低。排行第2的1号通风沟，其靠近风扇的末端，电动机的有效长度存在温度最低的区域。4号风沟的流动速度最小，它位于电动机的中央，并且在非风扇的顶端有一定的倾角，所以最热的地方就是这个位置。

3 动力系统永磁同步电动机热场分析 3.1 热载荷计算

 $q = \frac{{{P_{loss}}}}{{sl}} \text{。}$ (3)

3.2 边界条件

 $- \lambda \frac{{\partial T}}{{\partial n}}|\Gamma = \alpha (T - {T_\Gamma })\cdot \Gamma \text{。}$ (4)

3.3 转子、定子散热系数分析

 图 6 电动机转子热分布图 Fig. 6 Heat distribution map of motor rotor
 ${R_e} = \frac{{2{\delta _E}{\upsilon _e}}}{\upsilon } \text{，}$ (5)
 ${\upsilon _e} = {[\upsilon _\alpha ^2 + {(\upsilon R)^2}]^2} \text{。}$ (6)

 $\alpha = \frac{{\lambda {N_u}}}{{2\delta }} \text{。}$ (7)

3.4 计算结果

4 结　语

 [1] 汪远林, 窦满峰. 高功率密度永磁同步电动机散热设计及热场分析[J]. 微特电动机, 2013, 41(5): 23-24+31. WANG Yuan-lin, DOU Man-feng. Heat dissipation design and thermal field analysis of high power density permanent magnet synchronous motor[J]. Micro Motor, 2013, 41(5): 23-24+31. [2] 庄旭, 曾德俊, 曾令全. 基于FEM永磁同步电动机的分析与计算[J]. 东北电力大学学报, 2005, 25(6): 116-119,122. ZHUANG Xu, ZENG De-jun, ZENG Ling-quan. Analysis and calculation of permanent magnet synchronous motor based on FEM[J]. Journal of Northeast Electric Power University, 2005, 25(6): 116-119,122. DOI:10.3969/j.issn.1005-2992.2005.06.027 [3] 郭昱君, 王爱元, 姚晓东. 基于特征权值小波包能量分析的异步电动机电气故障特征提取[J]. 上海电机学院学报, 2022, 25(3): 142-148. GUO Yu-jun, WANG Ai-yuan, YAO Xiao-dong. Extraction of electrical fault features of asynchronous motors based on eigenweight wavelet packet energy analysis[J]. Journal of Shanghai Institute of Electrical Engineering, 2022, 25(3): 142-148. DOI:10.3969/j.issn.2095-0020.2022.03.004 [4] 丁杰, 张平, 李益丰, 等. 永磁同步电动机的三维流场温度场耦合计算[J]. 大功率变流技术, 2014(6): 6. DING Jie, ZHANG Ping, LI Yi-feng, et al. Coupling calculation of three-dimensional flow field and temperature field of permanent magnet synchronous motor[J]. High Power Converter Technology, 2014(6): 6. [5] 庞聪, 胡彬. 永磁同步牵引电动机的温升计算研究[J]. 防爆电动机, 2019, 54(2): 15-17. PANG Cong, HU Bin. Research on temperature rise calculation of permanent magnet synchronous traction motor[J]. Explosion-proof Motor, 2019, 54(2): 15-17.