双斜槽转子高效率低噪声感应电机的基础理论及实验研究

In order to achieve the design goal of high-efficient and low noise motor, this project focuses on the fundamental theory and experimental research for high-efficient and low-noise induction motor. The contents of the main research are as follows: 1) Explore the distortion theory of the air-gap flux density under double skew rotor condition and study the effects of the skew rotor on the fundamental and harmonics of the air-gap flux density. A suitable 3D mathematical model of complex air-gap flux density will be established next; 2) Obtain the distribution of air-gap flux density by finite element method and extract the harmonics by 2D fourier transform and analytical method; 3) Maxwell tensor method is applied to analyzing the electromagnetic excitation forces. An appropriate noise model is proposed by considering the influence of order, amplitude and frequency of the harmonics; 4) Inter-bar resistance will be introduced to establish high-frequency circuit to calculate the distribution of stray losses. Furthermore, different slot combinations, skew angles, slot types and segmented modes of the rotor will be discussed to analyze the electromagnetic noise and the distribution of the losses together with the performance of the motor; 5) According to the design theory, a prototype will be made to verify the reasonability and correctness of the theory. This project will change the situation of the noise and efficiency of the motor. It may satisfy the national demands of strategy of sustainable development greatly. It also has significant influence on high-efficient and low noise induction motor with an important practical value.

为了达到高效率与低噪声兼顾的目标，本项目开展双斜槽转子高效率低噪声感应电机的基础理论及实验研究。包括：1）探索双斜槽转子结构下的气隙磁场畸变原理，全面深入研究双斜槽转子对气隙磁场基波和谐波的影响，建立合适的复杂三维磁场数学模型；2）采用有限元法仿真获取气隙磁场分布，运用二维离散傅里叶法和解析法相结合提取时空谐波分量；3）运用麦克斯韦张量法分析电磁激振力，考虑电磁力的阶次、幅值、频率对噪声的影响，建立合适的电磁噪声模型；4）引入横向电阻建立高频等效电路模型，计算损耗分布状况，研究在不同槽配合、斜槽角度、槽型尺寸以及转子分段方式等多维参数变化下，电磁噪声以及损耗分布情况；5）根据上述原理，选择最佳参数，进行样机研制，验证理论分析的正确性。本项目的研究将改变长期以来我国感应电机效率与噪声水平无法兼顾的局面，满足节能减排的国家科技需求，对高效率低噪声感应电机的研制具有重大的现实意义和实用价值。

双斜槽转子电机具有高效率低噪声的特点，相比传统斜槽转子电机，双斜槽转子的应用可以大幅削弱气隙谐波磁场，同时基波磁场幅值降低不明显。本项目的主要研究成果包括：1）深入开展了双斜槽转子对气隙磁场畸变效应研究。建立了较为精确的气隙磁场三维数学模型，并考虑双斜槽转子对转子及饱和磁场分量轴向变化的影响。2）基于电机电磁噪声的分析和耦合仿真，对双斜槽转子关键参数的优化设计，并提出电机结构的创新从而改善噪声水平。3）双斜槽转子感应电机附加损耗的分析及计算。通过二次许克变换，精确计算中环区域空间磁场分析，并基于导体分层法计算转子涡流损耗。同时建立单位区域电路模型，在高低接触电阻率区间分别计算横向电流损耗。4）等槽或虚拟等槽配合时双斜槽转子电机的附加转矩研究。针对不同槽配合时的附加转矩特点，改进谐波转矩计算模型，增加了双斜槽转子槽配合的选择范围。本项目试制了若干台样机，验证了双斜槽转子设计方法的合理性，以及该电机在降噪提效等性能的优越性。本项目的研究在感应电机基础理论研究，以及电机优化设计方面取得了重要的进展，为高效率低噪声感应电机的研制具有重要的理论意义和实用价值。