Due to advantages such as high energy density, high power density, rapid charge and discharge, high cyclic-life, and environmentally friendly, flywheel energy storage systems (FESs) are widely used in various fields. However, the performance of FES systems depends on the performance of a high speed machine, therefore, the design and optimization of a high efficiency and high power density machi...

High torque and power density are unique merits of transverse flux machines (TFMs). TFMs particularly suitable for use in direct-drive systems, that is, those systems with no gearbox between the electric machine prime mover or load. Variable speed wind turbines in-wheel traction seem to be great-potential applications TFMs. Nevertheless, cogging torque, efficiency, factor manufacturing should s...

This paper presents an improved micro-step voltage-fed actuator for an automobile active grill shutter (AGS) system. A novel structured stepper motor, which contains both the main and auxiliary teeth in the stator, is proposed for the actuator. In a normal permanent magnet (PM) motor coils are generally wound on all the stator teeth, however, in the proposed motor, the winding is only on the ma...

This paper introduces a multi-objective optimal design for an axial magnetic gear (AMG). In this study, the condition high torque density and low cogging was deduced while cost of active materials also reduced. The number direction permanent magnets their arrangement were unchanged in optimisation process, considered AMG's main dimensions optimised using particle swarm method. AMG compared with...

Hybrid stepper motors (HSMs) are commonly used in many cost-sensitive industrial and consumer applications. With the use of micro-stepping techniques, they could theoretically achieve a very high resolution in positioning of mechanical loads, even without position sensors. However, it is well known that HSMs are affected by a large torque ripple, due to cogging and phase unbalancing. This, in t...

Permanent Magnet Synchronous Machine (PMSMs) are considered as the promising electromagnetic structure, especially for In-Wheel motor electric and hybrid propulsion applications. The design for a direct-drive wheel motor PMSM require a 3D Finite Element Analysis (FEA) based investigation of the output torque especially when the end winding is considered and in the case of skewed machine, this p...

In this paper, we present a mathematical model for determining the optimal radius of the iron pole shape in spoke-type permanent-magnet (PM) machines (STPMM) in order to minimize the pulsating torque components. The proposed method is based on the formal resolution of the Laplace’s and Poisson’s equations in a Cartesian pseudo-coordinate system with respect to the relative permeability effect o...

This contribution introduces a vector interpretation to unify the description of torque development in rotating electrical machines. The motivation behind this attempt is necessity applying different physical and calculation methods, such as Lorentz force, Maxwell stress tensor, co-energy methods etc., for predicting estimating components, e.g. synchronous torque, oscillating cogging reluctance...