In this paper, a new E-core hybrid reluctance motor (HRM) is proposed with permanent magnets (PMs), placed inside stator common poles. This motor is a 2-phase 12/16 HRM, which is characterized by a stator composed of four E-cores and a rotor with the same configuration of switched reluctance motors (SRMs). The three poles of each E-core are identified as a common pole in the middle with no windings and two excitation poles in the sides with concentric windings. The Windings of the excitation poles are wound such that both phases generate flux in the same direction as the PMs flux, so the demagnetization problem of the PMs is solved. The proposed motor is analyzed, and in order to illustrate the features and improvements, it is compared with two other well-established HRMs of the same size based on the simulation results obtained from the finite element analysis (FEA) method. Moreover, some parameters like average torque, output power and efficiency are compared, and it is illustrated that the proposed motor has better specifications compared to the other two. Finally, to verify the accurate design and operation of the proposed motor, its experimental verification is performed.

The demand for electrical machines has been spurred by rising fuel costs, technological advancements, and urbanization. Consequently, there is an increased focus on developing machines with greater power density, improved efficiency, and enhanced vibroacoustic characteristics while promoting a more sustainable supply chain. This paper offers a thorough comparison of three distinct motor topologies: switched reluctance motor (SRM), interior permanent magnet synchronous motor (IPMSM), and induction motor (IM). The study begins with electromagnetic analysis of the motors, covering torque, output power, losses, and efficiency calculations. Subsequently, the investigation delves into radial force density waveforms, extracting the dominant radial force density harmonics and presenting patterns for each motor’s dominant radial force harmonics. Following this, a 3D assembly of the motors is introduced for modal analysis, determining their mode shapes and natural frequencies. Finally, vibroacoustic analysis is conducted for the proposed motors, with observed differences being discussed. These analyses are conducted solely for the rated operating point, as transitioning to other operating points does not alter the pattern of radial force harmonics or the correlation between acoustic noise and radial force harmonics.

To design and manufacture electric machines that are competitive in terms of cost, performance, and efficiency, various parameters must be considered. Winding type selection and manufacturing are among these aspects. The winding needs to be designed optimally according to the electric machine type and application. Choosing the suitable magnet wire is one of the essential steps in winding design and manufacturing. For this purpose, several parameters need to be considered, including the diameter, thermal class, conductor type, and insulation material of the magnet wire. Also, the type and material of the bobbin should be selected properly. The tension applied to the wire during the winding process is an important parameter to achieve perfect layering and a high fill factor. Automatic winding techniques can be chosen according to the winding process requirements and the manufacturing volume. Different steps in the manufacturing process of electric machine coils are investigated in this paper, including the factors that should be taken into account to have a high-quality product. For design-for-manufacturing considerations, the approaches for selecting the proper magnet wire, insulation, bobbin, and layering technique are presented. Finally, different winding techniques are introduced, and their specifications and capabilities are discussed and compared.

This paper presents an experimental characterization of acoustic noise and sound quality in a 12/8 Switched Reluctance Motor (SRM) using hysteresis and Pulse Width Modulation (PWM) current control techniques. To overcome the limitations of traditional sound power measurements and enhance the accuracy of acoustic noise evaluation, a setup is applied for calculating sound power based on sound intensity measurements. The study provides a detailed description of the intensity probe-holding fixture, the hardware configuration for acoustic noise experiments, and the software setup tailored to specific measurement requirements. The acoustic noise characteristics of the motor are assessed at various operating points using two distinct current control methods: hysteresis current control with a variable switching frequency of up to 20 kHz and PWM current control with a fixed switching frequency of 12.5 kHz. Measurements of sound pressure and sound intensity enable the calculation of sound power and sound quality metrics under different operating conditions. Furthermore, the study investigates the influence of various factors on the motor’s sound power levels and sound quality. The findings provide valuable insights into the contributions of these factors to acoustic noise characteristics and offer a foundation for improving the motor’s acoustic behavior during the design and control stages.

This paper introduces a technique aimed at improving the performance of an interior permanent magnet synchronous machine (IPMSM) by reducing torque ripple and radial force harmonics. Unlike conventional IPMSMs, the proposed method employs a variable airgap length that is defined by a mathematical function. Two distinct rotor shapes are investigated to determine the most efficient design. Finite Element Analysis is employed to assess both the electromagnetic and mechanical attributes of the proposed motors. It compares the results for three operating points of the shaped motor with those of a conventional one. The investigation delves into the influence of rotor geometry on key output parameters, including Back Electromotive Force (back‐EMF) harmonics, average torque, cogging torque, torque ripple, efficiency, power factor, and radial force harmonics. The findings indicate that optimising rotor shape can significantly enhance IPMSM performance by reducing torque ripples and radial force harmonics, while simultaneously increasing average torque and efficiency at different operating points.

This paper presents the development of an electric motor with the novel Distributed High-Density (DHD) winding technology. The DHD winding technology utilizes round wires instead of bar wires. Unlike conventional round-wire winding technique (shed winding), the wires are orderly positioned in the slots in the DHD winding technology, resulting in high fill factor and high efficiency. The implementation of a stator with the DHD winding is presented which utilizes state-of-the-art coil winding and assembly processes. To compare against existing stator designs, a 100 kW, 800 V, and 15,000 RPM propulsion motor is tested experimentally to validate the performance of the DHD winding technology. The acoustic noise behaviour of the propulsion motor is also characterized experimentally. The motor efficiency with the DHD, hairpin, and shed windings are compared for the same stator geometry using simulation results to demonstrate the performance improvement with the DHD winding technology.