在特种电源系统中双Y同步发电机特性的分析

根据双桥换流器的换相机理，结合双Ｙ电机的基本方程，导出了双Ｙ同步发电机的电枢电流和端电压波形，并对其电枢磁势也进行了系统的分析推导。最后，用具体的实验与理论分析相比较，获得一些重要的结论。     

三输出直流发电机原理及设计特点

主要论述三输出直流发电机的基本原理及主要特点,对三输出直流发电机的磁场、电枢电动势、电枢电流的分布、电枢铜耗、电枢电压降、电枢反应以及换向磁势、换向绕组等方面进行了分析,并与一般直流发电机进行了比较。通过上述几方面的分析,提出三输出直流发电机的设计方法以及设计时所必须考虑的几个问题。     

六相电流型交直交变频同步电动机电枢磁势及转子表面附加损耗的分析

六相电流型交直交变频同步电动机不同于普通三相电机，除存在电机内在的时空谐波外（与三相同步电动机不同），还存在着变频电源注入的外加谐波。本对六相电流型交直交变频同步电动机电枢磁势的分布情况和计算方法进行了系统的分析推导。并在磁势分析基础上，给出了六相电流型交直交变频同步电动机转子表面附加损耗的计算方法，以供工程应用。     

移相升压自耦变压器的短路阻抗推导

对移相升压自耦变压器磁势进行了分析,介绍了用功率法推导移相升压自耦变压器短路阻抗计算公式的过程,并给出计算实例.     

隐极同步发电机转子等匝绕组励磁磁势分析

用富里哀级数对不同转子绕组形式的励磁磁势进行分析，通过基波幅值系数，电枢反应磁势折算系数和气隙磁通分布系数的对比和对各次谐波进行比较，最后得出了隐极同步发电机较好的转子等匝绕组方案。     

利用功率法推导移相自耦变压器阻抗

通过对移相自耦整流变压器磁势的分析,介绍了用功率法推导移相自耦整流变压器阻抗计算公式的过程,为移相变压器的阻抗计算提供了一种简单方法。     

同步发电机转子励磁电流的解析计算法

作者从工程实际出发,基于发电机的电势磁势图,通过一些合理的假设,推导出了同步电机不同工况下转子励磁电流的计算公式。其计算结果与保梯作图法求得的结果以及与试验值比较,相当接近。这种计算方法简便,如没有发电机的空载特性曲线,根据发电机的几个常用参数也能进行计算。它可用来计算发电机的调节特性、U形特性和配备无功功率。     

无刷直流电动机的设计(20)

9．2．2 二相导通星形三相六状态桥式线路 （1）导通状态分析 导通顺序：所谓二相导通星形三相六状态就是三相星形电枢绕组的每一个磁状态由二相电枢绕组同时通电所产生，整个一周由六个磁状态所组成，其导通顺序为UV→UW→VW→VU→WU→WV→UV。电枢磁势相量图如图51所示。     

关于六相双Y移30°绕组同步发电机的定子槽漏抗

文中指出,应用于3相同步发电机的定子槽漏抗计算公式不能简单地移用到6相双Y移30°绕组同步发电机的研究和设计中,并对6相同步电机的定子槽漏抗进行了分析,得出了相应的计算公式。同时,通过计算实例,对3相和6相的计算公式进行了比较分析,结果表明.本文提出的计算公式具有一定的工程实际意义。     

九相电动机谐波转矩研究

本文针对考虑空间谐波磁势影响的九相电动机谐波电磁转矩进行研究,分析了九相电动机空间谐波磁势,提出了一种考虑空间谐波磁势的电磁转矩计算方法,详细计算推导出了谐波电磁转矩的计算公式.从该公式可以看出,谐波电磁转矩有正转和反转两种.其中反转电磁转矩对电动机运行有害,应该尽量消除或减小.本文所提出的谐波电磁转矩计算方法为多相电动机转矩分析提供理论依据     

六相同步发电机的稳态电磁参数

从Park方程的基本原理出发,建立了六相同步发电机的基本方程,得到了六相同步发电机的d轴等值电路和q轴等值电路。等值电路中的综合互感抗体现了六相同步发电机2个Y之间的磁耦作用,由电枢反应电抗和综合漏互感抗2部分组成。通过对六相同步发电机单Y运行(另一Y开路)和双Y运行的分析,得出双Y运行同步电抗为2倍的单Y运行同步电抗与单Y自漏抗之差。以空载短路试验的实例,测试了六相同步发电机特性曲线,以及d轴同步电抗、自漏抗和短路比。从电磁理论分析和实际运行特性2方面,验证了六相同步发电机的稳态电磁参数。     

A study on eddy-current losses in rotors of surface permanent-magnet synchronous machines

In this paper, we investigate the Eddy current (EC) losses in the rotors of surface permanent-magnet (PM) synchronous machines, which have concentrated armature windings. By the finite-element method (FEM) analysis, it is clear that the EC losses in rotors are apparently different at rated currents if the pole and slot combinations are different. The distribution of the EC density in the rotor is closely related with the asynchronous components of the armature magnetomotive force (MMF). If the armature MMF has a low order of spatial harmonic components, which is not synchronous with the rotor, the EC losses are of large amounts.     

Characteristics of a brushless and exciterless three-phase synchronous generator with DC exciting system

From the viewpoint of maintenances and constructions, it is desirable that brushless and exciterless type three-phase synchronous generators be made. To meet this requirement, one of the authors devised a brushless and exciterless synchronous generator in which exciting currents flow simultaneously with load currents in armature windings. Thus, generators can be used both as the generators themselves and as the exciters. A generator system has already been reported by one of the authors. In it, the dc stator exciting current flows between the middle points per phase of the double-star armature winding through the rectifiers. However, the winding connection between the armature winding and the rectifiers are complicated. Three sets of rectifiers are needed by the stator excitation. The authors present a generator system by which the electric connection of between the stator armature winding and the rectifier can be simplified, and the number of the rectifiers can be reduced. In this system, the stator is provided with a double-star armature winding having two neutral points. In this paper, first, a circuit constitution and the principle for the brushless and exciterless three-phase synchronous generator are described, and second, the characteristics are elucidated by means of characteristic analysis. Further, the results of the experiments for the generator conducted on the test machine of 2.0 kW are shown.     

具有耦合电路的运动磁场分析

本文首先提出一种分析运动磁场模型的有限元剖分方法,通过三相凸极同步发电机空载电压谐波计算证明了该剖分方法的简便性和实用性。然后阐述了电路和运动磁场间耦合关系的处理方法,从而使瞬变磁场计算和电路动特性仿真同时得解。文中给出同步发电机三相突然空载短路的例证。     

直流发电机与同步发电机交轴电枢反应的比较研究

主要解释了现行电机学书籍中关于直流发电机和同步发电机交轴电枢反应的差异.通过引入有效磁通的概念,理清了电机学中每极磁通概念的混乱;通过引入视在磁通的概念,使交轴电枢反应的效应在直流发电机和同步发电机中统一起来,维护了电机学内在的逻辑一致性.     

Use of permeance-based air-gap flux density analysis in the development of a synchronous generator model

The magnetic flux inside a synchronous generator is regarded as a characteristic that dominates a generator operation. This paper develops a simple model of a synchronous generator by which it is possible to easily estimate an air-gap flux as well as electrical characteristics. The air-gap flux density can be related to a permeance and a magnetomotive force (mmf) along its magnetic path by the Ampere's laws. These relations are used in this paper. We estimate the distribution of the permeance along the air-gap and the mmf profiles of the stator and the rotor of a 6 kVA scaled-down tested synchronous generator. From these estimated profiles, the relations among the air-gap flux, field current, and armature current are represented by a linear equation system. Consequently, the static electrical and magnetic characteristics of a synchronous generator can be estimated by giving only field exciting voltage and load impedance. The distributions of the air-gap flux density and waveforms of the field and armature currents are simulated for various unbalanced-load conditions. The simulated results well agree with experimental ones not only for fundamental components but also for higher harmonic components. Therefore, our method, based on the permeance profile, is available to calculate the static characteristics of synchronous generators.     

双绕组发电机交流侧带负载时直流侧突然短路的电磁转矩

根据双绕组发电机与普通三相同步发电机的内在关系,参照三相电机突然短路电磁转矩的分析方法,进行了双绕组发电机交流侧带负载时直流侧突然短路的电磁转矩解析分析,得到了简明的交变转矩、平均转矩及总电磁转矩的解析式,并通过试验进行了验证。所得双绕组发电机交流侧带负载时直流侧突然短路电磁转矩的计算式简明、准确、物理意义明确,特别适合于工程应用。     

励磁电流脉动对电枢绕组空载电压波形的影响

为了不影响齿谐波励磁的混合励磁永磁同步发电机的运行性能,需要正确处理好齿谐波磁场的利用与电枢绕组电压波形畸变两者之间的关系,此为利用齿谐波实现混合励磁的关键问题。应用电机理论定性分析了齿谐波励磁系统输出的励磁电流产生脉动的原因,以及该脉动电流产生的附加磁场在电枢绕组中感应谐波电动势的特点。采用在齿谐波励磁系统直流侧并联电容的方法,可以减小励磁电流的脉动,从而削弱其在电枢绕组中引起的谐波电动势。对一台齿谐波励磁的混合励磁永磁同步发电机进行了计算和实验,计算结果和实验结果的比较验证了理论分析的正确性。