为抑制永磁同步电机齿槽转矩,减少电机振动与噪声,提出一种定子齿顶开辅助槽与转子外圆偏心的结构来抑制齿槽转矩,提升电机的输出性能.首先建立了定子齿顶开槽前后与主气隙分布函数解析式,分析定子开槽与电机主磁场分布及齿槽转矩的关系,同时分析了转子外圆偏心后对齿槽转矩的影响.以内置 3 相 8 极 48 槽V型永磁同步电机为例,利用有限元法对定子齿顶辅助槽个数、槽宽、槽深、槽位置以及转子外圆偏心距等参数进行优化对比分析,获得最优的参数匹配.结果表明:定子齿顶双矩形对称开槽以及转子外圆偏心的方式能有效改善主气隙磁场分布,抑制电机齿槽转矩,优化后的电机气隙磁密 5、11、15、17 谐波幅值下降明显,电机齿槽转矩峰值降低了 59.6％,反电势波形正弦性增强,平均转矩提升,电机输出性能明显改善.

针对永磁同步电机输出转矩大、气隙磁密接近正弦曲线和低齿槽转矩等要求,提出了一种新型非对称磁极永磁电机结构并分析其电磁特性.建立转子外缘数学模型,利用解析法分析电机输出性能与转子偏心程度的关系式;利用有限元分析法,对比不同偏心程度下电机结构的气隙磁密、感应电动势和齿槽转矩,选取最优偏心距试制样机并进行试验.仿真分析和试验结果表明:所提非对称磁极永磁电机转子结构能够有效改善气隙磁密波形,且当转子偏心距为8 mm时,气隙磁密总谐波失真和齿槽转矩最小,分别为28.9％ 和280.8 m N·m.

针对偶数极分块转子磁通切换发电机存在偶数次谐波,导致感应电动势正负半周期波形不对称问题.建立了解析数学模型并推导出不同时刻、不同位置转子磁导引起的定、转子磁势的变化,进而达到削弱偶数次谐波的目的.提出了一种在分块转子内增加气隙磁障的新型拓扑以削弱感应电动势中的偶数次谐波.通过有限元仿真得到了传统的和带磁障的两种电机的磁链和感应电动势,并通过傅里叶分析得到各次谐波含量,证明了解析方法的正确性.依据上述理论试制了样机并进行实验,仿真和实验结果表明:加入气隙磁障后,12/8极分块转子感应电动势正负半周期波形近乎对称,相比于传统分块转子磁通切换发电机,虽然感应电动势基波幅值减小了14.9％,但是电压波形畸变率降低了88.2％,验证了所提方法的正确性,从而为偶数极分块转子谐波的削弱提供了一种新的解决方式.

In order to improve the air-gap flux density of the permanent magnet synchronous motor and reduce the cogging torque, a novel structure with asymmetric magnetic poles for automobile was proposed. Based on the characteristics of the parallel magnetic circuit, the magnetic flux path diagram is established. And the equivalent magnetic circuit model is established by the equivalent magnetic circuit method. The Taguchi method is used to be a multiobjective optimization algorithm. The total harmonic distortion of the air-gap flux density is the first optimization goal. The second and third optimization goals are the cogging torque and the average of output torque, respectively. And the torque ripple is a constraint condition. The optimized parameter combination is obtained by the Taguchi method. Finite element simulation analysis and prototype test are carried out for the optimized motor structure. The results show that the total harmonic distortion of air-gap flux density is reduced by 36.7% comparing with the initial structure. The cogging torque is reduced by 26.0%. And the average output torque is increased by 4.8%.

洞门密封施工是确保盾构安全始发、正常掘进的关键环节.本文提出了一种新型膜袋注浆辅助封堵洞门施工技术,在洞门钢环内壁与帘布橡胶交界处预装环形膜袋注浆密封装置,待盾体全部进入隧道,盾尾刷通过帘布橡胶后,在盾体外壁与围岩之间形成可注浆的封闭空间,达到洞门封堵止水的效果,然后盾构继续推进.本技术在青岛市地铁6号线应用,解决了下穿回填块石层、淤泥质粉质粘土层及强风化、"上软下硬"地层,临海、富水等复杂地质情况盾构始发安全难题,为今后类似工程提供借鉴.

螺纹锚固单边螺栓是指通过带有螺纹的特殊螺栓孔代替螺母,从而实现单侧安装、拧紧功能的一种螺栓.目前关于该种螺栓连接T形节点在常温下不同破坏模式的受拉承载力计算方法已有研究.但在高温条件下节点变形增大,且高强螺栓与普通钢材在高温下的材性折减规律不一致,导致现有的常温计算公式不能直接用于火灾高温情况,目前仍缺少计算该类节点在高温下承载力的计算方法.根据常温下承载力计算公式,结合高温下节点出现大变形的特点,对现有的计算公式进行修正.并根据现有的试验结果对修正公式进行验证,发现提出的设计公式可准确预测不同节点在不同温度下的破坏模式,也可以较为精确地预测其屈服承载力.

双层斜开槽钢板剪力墙由两层开有斜槽的薄钢板组成,两层钢板上斜槽的方向相反,通过橡胶层粘接在一起,具有相同的平面外变形.在水平荷载作用下,双层斜开槽剪力墙中,一层钢板上的斜向板带受拉,另一层钢板上的斜向板带受压.通过受拉斜向板带对受压斜向板带提供平面外支撑,减小受压斜向板带的平面外屈曲变形,形成自防屈曲机制.提出了用于双层斜开槽钢板剪力墙承载力和抗侧刚度计算的等效杆系模型,采用位于斜向板带中心线的等效杆件来代替斜向板带;等效杆件的截面宽度和截面高度与所替代的斜向板带的宽度和厚度相同.通过等效杆系模型和壳单元有限元模型,研究了剪力墙高宽比、高厚比、斜向板带宽度等对双层斜开槽钢板剪力墙受力性能的影响.等效杆系模型和壳单元模型分析结果的对比表明,等效杆系模型具有较好的适用性.

The field winding of conventional multiphase doubly salient electro-magnetic generator is wound across multiple stator poles. There is a problem that the flux paths of the respective phases are not completely symmetrical. A novel E-core stator was proposed, the basic topology of the multi-phase E-core doubly salient electro-magnetic generator (E-core DSEG) with symmetrical phase magnetic circuits is derived by using the electrical formulas. This establishes a theoretical basis for the design of multiphase E-core DSEG. Based on the finite element simulation software, the static characteristics of multi-phase E-core DSEG were analyzed, including magnetic field distribution no-load electromotive force, flux linkage, self-inductance of field winding, cogging torque and so on. Finally, a prototype of three phases 18/20-pole generator was made and tested. The rationality of theoretical analysis and generator topology was verified by simulation and experiment.

传统电励磁双凸极发电机励磁绕组跨多个定子极绕制,存在励磁磁路较长、铁损耗大、各相磁路不完全对称等问题.为了提高故障隔离能力并实现各相对称,提出一种由E型定子铁心组成的短磁路模块化电励磁双凸极发电机.针对所提出的集中绕组E型定子铁心,在分析转子极弧系数对各绕组电感影响规律的基础上,推导出三相发电机的定/转子极数比,励磁定子极、电枢定子极和定子槽口对应的极弧角度的约束公式,为电机进行电磁设计奠定基础.利用有限元软件对三相9/10极和三相18/20极电机的各相电动势、电感等瞬态特性进行建模分析.根据Bertotti分离铁耗模型计算出新型三相18/20极与传统三相18/12极电机的铁损耗值,并通过仿真验证了新型三相18/20极具有较低的铁损耗.最后,试制一台三相18/20极的样机并进行了实验,实验结果验证了理论分析和电机结构的合理性.

In this paper, an flux barrier is added in rotor to solve the positive and negative half cycle asymmetry of the phase winding back electromotive force(EMF) in flux switching motor with segmental rotor(SFSM). By analyzing the mathematical model, it is deduced that after the flux barrier is increased on the rotor, the change of permeability will lead to the change of the air gap magnetic density of the motor. Through the finite element (FEM) parametric simulation, the optimal size of the flux barrier is obtained. The FEM analysis shows that the motor has a high sinusoidal inductance waveform compared with the traditional motor, and the even harmonics in the back EMF of the phase winding are greatly weakened. Finally, an prototype is manufactured, and the experimental results verify the correctness of the proposed topology.

To improve the output current of an Integrated Starter Generator (ISG) with stable windings at high speed, a 3/6-phase winding switching permanent magnet (PM) machine is proposed this paper. At low-speed starting mode, large number of coils are series connected as conventional three-phase windings to keep the starting performance in starting the engine. At high-speed generating mode, the coils are connected as six-phase winding to generate greater current. Finite element analysis software was utilized to verify the EMF and output current performance of 3/6-phase winding switching of ISG with consequent-pole rotor, which was designed for Range Extender Electric Vehicles (REEV). The experimental results verified that the proposed ISG increased the output current by six-phase windings in generating mode.

To present the characteristics of pole number and pole shape of the core, the five-phase wound-field doubly salient generators (WFDSGs) with symmetric phase inductance are studied and optimised in this paper, considering the split ratio, slot fill factor and core fringing effect. Based on the principle and structure of the five-phase WFDSGs, the winding induced electro-motive force under different number of poles is theoretically analysed. The constraints for parameter optimisation design including slot fill factor, split ratio and magnetic density characteristic are given. The finite element models of 30/24-pole and 20/16-pole WFDSG are established, and the comparative simulation analysis is carried out. It is pointed out that when the inner and outer diameters of the stator and rotor, the axial length and the maximum magnetic density are constant, the induction electromotive forces of the WFDSGs with different pole numbers and same phase coil number are same. Considering the pole fringing effect, the rotor pole equivalent width is the sum of the rotor pole actual width and 4 times of the air gap. The comparison experiments between the 30/24-pole and 20/16-pole WFDSGs were carried out, which verified the correctness of the theoretical analysis and finite element analysis (FEA).