E.A. Lomonova

General Formulation of the Electromagnetic Field Distribution in Machines and Devices Using Fourier Analysis

We present a general mesh-free description of the magnetic field distribution in various electromagnetic machines, actuators, and devices. Our method is based on transfer relations and Fourier theory, which gives the magnetic field solution for a wide class of two-dimensional (2-D) boundary value problems. This technique can be applied to rotary, linear, and tubular permanent-magnet actuators, either with a slotless or slotted armature. In addition to permanent-magnet machines, this technique can be applied to any 2-D geometry with the restriction that the geometry should consist of rectangular regions. The method obtains the electromagnetic field distribution by solving the Laplace and Poisson equations for every region, together with a set of boundary conditions. Here, we compare the method with finite-element analyses for various examples and show its applicability to a wide class of geometries.

Modeling of Magnetically Levitated Planar Actuators With Moving Magnets

This paper presents three types of magnetostatic models of ironless planar actuators with moving magnets. The models predict the force and torque exerted on the translator of the actuator, which can be positioned in six degrees-of-freedom with respect to the stator coils. The force and torque are calculated with the Lorentz force law. The analytical and numerical models can be used for the design of large planar actuators, for the fast comparison of actuator topologies, and in the decoupling and commutation algorithm. The models have been verified with experiments

Analytical Hybrid Model for Flux Switching Permanent Magnet Machines

With the emergence of energy related issues in the automotive sector, there is a tendency to find new efficient solutions to replace existing electrical machinery. One promising candidate is the flux switching permanent magnet machine (FSPMM). Due to its challenging structure and nonlinear characteristic, in the investigation of the machine, generally finite element method (FEM), and rarely the magnetic equivalent circuit (MEC), are implemented. The following paper introduces an alternative analytical modeling technique by means of a hybrid model, which combines the advantages of the MEC and the Fourier analysis.

Magnetically Levitated Planar Actuator With Moving Magnets

This paper concerns the design, optimization, and commutation of a six-degree-of-freedom planar actuator with an active magnetic bearing. The planar motor has a stationary coil array and a translator with a Halbach magnet array. During movements in the plane, the set of energized coils changes with the position of the translator. In this paper, a method for the electromagnetic design of this type of actuator is discussed, and several topologies are compared. The best performing topology in terms of power dissipation and force and torque ripples has been manufactured and successfully tested.

Flux-Switching Machine With DC Excitation

This paper proposes a topology of flux-switching machine with dc excitation to improve the field-weakening capability of flux-switching machines. This dc-excited flux-switching machine preserves the structure of typical flux-switching permanent-magnet machines while replacing the permanent magnets with dc field windings. The combined advantages of this type of machine in torque production and field weakening are exhibited and validated by finite element analysis.

Modeling of Flux Switching Permanent Magnet Machines With Fourier Analysis

For applications demanding a high torque density and high speed capability, the flux switching permanent magnet machine is an excellent candidate. However, the double salient structure and nonlinear behavior increases the challenge to model the magnetic field distribution and torque output. To date, only the magnetic equivalent circuit (MEC) is employed to model the magnetic field in an analytical manner. However, the MEC method suffers from a coarse discretization and the need for a relative complex adjustment when rotor movement or a parametric sweep is considered. Therefore this paper discusses an alternative technique based on the harmonic or Fourier model which solves these difficulties.

Design Aspects of an Active Electromagnetic Suspension System for Automotive Applications

This paper is concerned with the design aspects of an active electromagnet suspension system for automotive applications which combines a brushless tubular permanent-magnet actuator with a passive spring. This system provides for additional stability and safety by performing active roll and pitch control during cornering and braking. Furthermore, elimination of the road irregularities is possible, hence, passenger drive comfort is increased. Based upon measurements, static and dynamic specifications of the actuator are derived. The electromagnetic suspension is installed on a quarter-car test setup, and the improved performance using roll control is measured and compared with a commercial passive system. An alternative design using a slotless external-magnet tubular actuator is proposed which fulfills the thermal and volume specifications.

Comparison of Position-Independent Contactless Energy Transfer Systems

This paper presents a comparison of position-independent contactless energy transfer systems by means of an inductive coupling, as a solution to overcome moving cables in emerging mechatronic applications with a linear moving load. A 2-D electromagnetic model of the contactless energy transfer system is derived and applied to six different topologies, which have either air-cored coils or a combination of salient or nonsalient magnetic cores. A parametric sweep is performed to obtain an optimal parameter set for each topology, suited for a power transfer of 1 kW with a position-independent mutual inductance between the primary and secondary coils. Comparison among the topologies shows that slotted topologies are less suited for a constant power transfer and that the geometry can be optimized for a mutual inductance variation below 3% along the linear movement.

Modeling Ironless Permanent-Magnet Planar Actuator Structures

This paper describes an analytical model that includes end effects for ironless synchronous permanent-magnet planar actuators. Because of its flexibility, the model can be used to predict the performance of various permanent-magnet array and coil array topologies and commutation schemes. Moreover, since control currents have to be nonsinusoidal, it allows analysis of the motor performance without specifying a commutation scheme by directly dealing with the motor-coupling matrix that links the coil currents to the forces or accelerations acting on the translator

Coil Array Structures Compared for Contactless Battery Charging Platform

We propose two new coil topologies for a contactless battery charging platform. The new topologies consist of square printed circuit board (PCB) coils, grouped in two layers on a PCB. We compare the new topologies to each other and to a previously published topology that consists of three layers of hexagonal coils. For each topology, the magnetic flux density is calculated above the coil layers. In addition, the position dependence of the flux linkage between the primary coil array and a secondary coil is simulated and compared for all three topologies. For one of the new topologies, we compare the simulations with measurements.