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.

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.

The voltage harmonics of the six-phase doubly salient electro-magnetic generator (DSEG) are large, and the electromagnetic isolation is poor due to the mutual inductance of the armature winding. An optimization scheme for the stator non-uniform air gap structure is proposed. By establishing a non-uniform air gap angle function model, the analytical expression of the induced electromotive force in the non-uniform air gap structure is derived. Using finite element and mathematical model to verify that the stator tip is changed from circular arc to linear structure can increase power and reduce voltage high harmonics, improve the power quality of the generator. Based on the equivalent magnetic circuit, the influence of the winding method of the excitation winding on the mutual inductance of the armature winding is studied. When the field winding is wound interval every two stator poles, the mutual inductance is small. The electromagnetic properties of the new six-phase electric excitation double salient pole are analyzed by two-dimensional finite element analysis. The rationality of the proposed motor structure is verified by experiments.

The switched reluctance starter generator (SRSG) without field winding and the doubly salient electromagnetic starter generator (DSESG) with field winding are compared in this paper. The influences of two arrangements of each variable winding and spacing variable winding for the performance of the starter generator were studied. Mathematical models of start mode and power generation mode were established respectively, and the influencing factors of starting torque and power generation phase voltage were derived. Next, the finite element simulation software was used to simulate the electromagnetic characteristics of machine. Finally, prototype experiment was made. The finite element simulation and prototype experiment results proved that spacing excitation DSESG has a better prospect as automotive starter generator.

To satisfy the requirement of high torque in starting state and accurate voltage regulation in generating state, a Dual-Mode Starter Generator (DMSG) with variable winding is proposed in this paper. Firstly, the influence of winding parameters on the performance of DMSG is analyzed by establishing the mathematical model of equivalent turns. Next, the cause of circulating current in starting state is analyzed. In order to solve the problem of circulating current between parallel branches, this paper presents a method that adding directional diode in main power circuit. The correctness of this method is verified by simulation. Then, the optimal matching relationship between the field winding and armature winding with multi-objective optimization is determined. At last, the FEA and prototype experiments verify the feasibility and performance of starter mode and generator mode of the DMSG.

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).