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Inductance, torque and iron loss are the key parameters of switched reluctance motors for belt-driven starter generators. This paper aims to present the analysis of a segmented rotor switched reluctance motor (SSRM) with three types of winding connections for hybrid electric vehicle applications by using a two-dimensional finite element method.

The rotor of the studied SSRM consists of a series of discrete segments, while the stator is made up of exciting and auxiliary teeth. First, the concept and structures of the different winding connections are introduced. Then, the magnetic flux path of the three types of winding connections for the SSRM is described. Second, the magnetic flux distributions in the three parts, i.e. the stator yoke, the stator tooth and the rotor segment, are described in detail to calculate the iron losses. Third, three SSRMs with the different winding arrangements are analyzed and compared to evaluate the distinct features of the studied SSRM. The analysis and comparison mainly include self-inductances, mutual inductances, phase currents, output torque and iron loss.

It is found that the self-inductances of the three types of winding connections are almost equal, and only the SSRM1 has a positive mutual inductance. In addition, the current waveforms of SSRM1 and SSRM2 are regular. However, it is irregular in SSRM3. It is shown that SSRM1 has better characteristics, such as higher output torque, high power density, lower torque ripple and iron loss.

This paper proposes and analyzes three novel winding connections for the SSRM to provide guidance for enhancing the output torque and reducing the iron loss to achieve high efficiency.

This paper aims to propose an effective method to verify poles polarities of switched reluctance motors (SRMs). Different from the ways of detection poles polarities by permanent magnet in SRMs, the difference of self-inductance between different winding connections is used to verify the pole polarity.

First, the winding connections with the forward and reverse series are proposed. The magnetic circuit models are established to analyze the flux linkage of different winding connections. Then, according to the difference of inductance characteristics, including the self-inductance and the mutual inductance affected by the adjacent poles, it is theoretically feasible to verify the polarity of each pole. Finally, the proposed method is verified by the simulation and experiment on a six-phase SRM.

First, compared to the reverse series, the forward series can produce larger self-inductance when one phase is excited at the same current excitation, which can be used to verify the poles polarities of one phase with different winding connection. Second, the mutual inductance can be used to distinguish the winding connections. Third, the difference of the maximum self-inductance of the winding, which is composed of two adjacent windings, can be used to verify the polarities of the adjacent poles.

This paper proposes an effective method to verify poles polarities of SRMs.

The purpose of this paper is to analyze the phase coil connections and winding factors of flux‐switching permanent magnet (FSPM) brushless AC machines with all poles and alternate poles wound, and different combinations of stator and rotor pole numbers.

The coil‐emf vectors, which are widely used for analyzing the conventional fractional‐slot PM machines with non‐overlapping windings, are employed for FSPM machines.

Although the coil‐emf vectors have been employed to obtain coil connections in the conventional fractional‐slot PM machines, they are different in FSPM machines. It is mainly due to different polarities in the stator of FSPM machines. In addition, from the coil‐emf vectors it is able to predict whether the back‐emf waveforms are symmetrical or asymmetric.

This is the first time that coil‐emf vectors are used to determine the coil connections and winding factors in FSPM machines with different topologies and combination of stator and rotor pole numbers.

The purpose of this paper is to study the multi-objective optimization design method of high-power high-frequency magnetic-resonance air-core transformer (ACT).

First, this paper studies the interleaved winding technology, the process of modeling and simulation, the calculation method of high-frequency loss of Litz wire and the design of magnetic shielding in detail. Second, the multi-objective optimization design process of high-frequency magnetic-resonance ACT is established by parametric scanning method and orthogonal experiment method.

An ACT model of 2 kV/100 kW/81.34 kHz was designed. The efficiency, weight power density and volume power density are 99.61%, 21.6 kW/kg and 5.1 kW/kg, respectively. Finally, the multi-physical field coupling simulation method is used to calculate the port excitation voltages and currents and temperature field of ACT. The maximum temperature of the ACT is 95.5 °C, which meets the design requirements.

The above research provides guidance and basis for the optimization design of high-power high-frequency magnetic-resonance ACT.

The electromagnetic torque oscillations caused by saturation harmonics in a squirrel cage machine are analysed. Special attention is paid to the most important saturation harmonic of alternating field that has three times as many poles as fundamental harmonic and three times its frequency. The operations of the machine as a motor and as a self‐excited generator have been investigated. The 2D finite element time‐stepping method has been applied to the analysis of a particular machine performance. The finite element equations are coupled with circuits equations which describe the winding connections. The skew of the rotor slots is taken into account.

This paper aims to obtain a symmetrical step-down topology with lower equivalent capacity and wider step-down range under the condition of the same output. Two new symmetrical step-down topologies of star-connected autotransformers are proposed in this paper. Taking the equivalent capacity as the main parameter, the obtained topologies are modeled and analyzed in detail.

This paper adopts the research methods of design, modeling, analysis and simulation verification. First, the star-connected autotransformer is redesigned according to the design objective of symmetrical step-down topology. In addition, the mathematical model of two topologies is established and a detailed theoretical analysis is carried out. Finally, the theoretical results are verified by simulation.

Two symmetrical star-connected autotransformer step-down topologies are designed, the winding configurations of the corresponding topology are presented, the step-down ranges of these three topologies are calculated and the influence of step-down ratio on the equivalent capacity of autotransformer are analyzed. Through analysis, the target step-down topologies are obtained when the step-down ratio is [1.1, 5.4] and [1.1, 1.9] respectively.

Because the selected research object is only a star-connected autotransformer, the research results may lack generality. Therefore, researchers are encouraged to further study the topologies of other autotransformers.

This paper includes the implications of the step-down ratio on the equivalent capacity of autotransformers and the configuration of transformer windings.

The topologies designed in this paper enable star-connected autotransformer in the 12-pulse rectifier to be applied in step-down circumstances rather than situations of harmonic reduction only. At the same time, this paper provides a way that can be used to redesign the autotransformer in other multi-pulse rectifier systems, so that those transformers can be used in voltage regulation.

The paper presents a method for the 3D edge element analysis of saturation effects in the classical rotating electrical machines of cylindrical structure. The edge element (EE) method using vector magnetic potential has been applied. Special attention is paid to the saturation effects in permanent magnet motors. In order to solve the non‐linear EE equations the authors propose to apply the modified Newton algorithm with block relaxation solver and Cholesky decomposition procedure for block matrices. The convergence of the algorithm is analysed. The influence of core non‐linearity on the values of electromagnetic torque and armature inductances is considered. The results for 3D and 2D models are compared.

WITH THE RAPID GROWTH of world airline investment in powered ground equipment, much closer attention is being given to the development of fixed rather than mobile ramp services, for electrical, air starting, lavatory and water servicing of aircraft. Mobile Ground Power Units account for a large proportion of the capital investment, often at the highest unit cost.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

The purpose of this paper is to present a modification of the Park variable transformation for a three‐phase wye‐connected winding without neutral wire. A new physical interpretation of the winding equivalent circuit is proposed.

An equivalent circuit representing reluctance motor stator winding is rearranged to enable easier physical interpretation of obtained voltage equation. The Park transformation and constraints resulting from Kirchhof's laws are then applied to obtain a two‐axis mathematical model of the motor.

A new physical two‐phase interpretation of the voltage equation for a three‐phase wye‐connected winding without neutral wire is proposed. A novel two‐axis transformation is formulated for all variables. Compared to the Park transformation, which is the same for all variables, in the proposed transformation its matrices for currents and voltages/flux linkages are different, yet strongly interconnected.

The proposed transformation is formulated for a specific type of winding connection scheme. Therefore, it is limited in its application.

From the practical point of view, the proposed transformation could be very useful as it applies to the most popular stator winding connection scheme. Its main advantages are fewer number of trigonometric parameters in the matrices and measurability of all currents and voltages present in its voltage equations. It could be of special importance for electric machines with non‐sinusoidal field distribution (e.g. Brushless DC).

The paper presents a new type of variable transformation for three‐phase electric machines with wye‐connected windings without neutral wire. Proposed transformation combines different transformations for currents and voltages/flux linkages.