Hybrid analytical modeling of saturated linear and rotary electrical machines:integration of fourier modeling and magnetic equivalent circuits

\u3cp\u3eThis paper presents a 2-D hybrid analytical modeling method for the analysis of the magnetostatic field distribution with the capability of including nonlinear materials. The model combines Fourier modeling, which is accurate and fast, with meshed magnetic equivalent circuits that have unique permeability in mesh elements and, therefore, can model local saturation. To present the diverse applicability of the proposed method, it is applied to a linear machine with permanent magnet excitation and a rotary machine with current excitation. Magnetic field calculations are compared with finite-element analysis (FEA) with good agreement.\u3c/p\u3

Dynamic analysis of a tubular generator for automotive suspension applications

In this paper, a slotless three-phase tubular permanent magnet generator applied to vibration energy harvesting in automotive suspensions is considered. A two-dimensional finite element method model of the harvester is created as well as an experimental setup, containing the generator. Signal decomposition utilizing Fourier series is applied to suspension displacement data and the resulting signal components are applied to the model. The individual responses of the model are superposed, from which the corresponding harvested energy is derived. Comparisons are made with measurements on the setup that act as reference to determine the error of the harmonic reconstruction

Series hybrid vehicle system analysis using an in-wheel motor design

Hybrid vehicles, which employ a technology combining gasoline and electric motors, are a hot item these days for transporters looking for ways to cut their fuel bills. To date, commercial systems implement diesel assisted electrical drives. As such the electrical motor is placed in a series or parallel configuration to assist the combustion engine. In the series configuration, the generator mounts directly to the engine, and most of the engine power is converted into electric energy to drive the traction motors at the axle/wheel ends. This enables the exclusion of the mechanical drive path between the engine and the drive wheels

High-order methods applied to nonlinear magnetostatic problems

This paper presents a comparison between two high-order modeling methods for solving magnetostatic problems under magnetic saturation, focused on the extraction of machine parameters. Two formulations are compared, the first is based on the Newton-Raphson approach, and the second successively iterates the local remanent magnetization and the incremental reluctivity of the nonlinear soft-magnetic material. The latter approach is more robust than the Newton-Raphson method, and uncovers useful properties for the fast and accurate calculation of incremental inductance. A novel estimate for the incremental inductance relying on a single additional computation is proposed to avoid multiple nonlinear simulations which are traditionally operated with finite difference linearization or spline interpolation techniques. Fast convergence and high accuracy of the presented methods are demonstrated for the force calculation, which demonstrates their applicability for the design and analysis of electromagnetic devices

Electromagnetic actuator with integrated passive damper

An electromagnetic actuator (100) comprises magnets (109, 111, 113, 115, 11), and a ferromagnetic structure (103) accommodating control conductors (118, 121, 123, 125). The magnets and the structure can move with respect to one another under control of control currents in the control conductors. The magnetic field in a gap (107) between the magnets and the ferromagnetic structure is oriented perpendicular to the direction of relative movement. The structure (103) accommodates damping conductors (127) that form closed loops of an electrically conductive material, different from the ferromagnetic material. The damping conductors (127) provide a damping force induced by the relative movemen

Magnetic saturation in semi-analytical harmonic modeling for electric machine analysis

A semi-analytical method based on the harmonic modeling (HM) technique is presented for the analysis of the magneto-static field distribution in the slotted structure of rotating electric machines. In contrast to the existing literature, the proposed model does not require the assumption of infinite tooth permeability, material property homogenization, or a hybrid modeling approach. In fact, the permeability variation in the slotted machine parts is embedded directly into the magnetostatic field solution. Currently, only linear soft-magnetic materials with finite permeability are considered. However, non-linear materials could be considered iteratively, and therefore the proposed model presents a first step toward including the magnetic saturation effects into HM. To validate the presented method, semi-analytical models are implemented for two benchmark topologies with slotted rotors. Magnetic field calculations are performed for two different values of linear rotor tooth permeability and compared to finite-element analysis predictions. The results\u3cbr/\u3eshow that a very good agreement is obtained

Analysis of variable flux reluctance machines using hybrid analytical modelling

\u3cp\u3eIn this paper, an extended hybrid analytical modelling (HAM) technique is presented and applied to a variable flux reluctance machine (VFRM). The saturation phenomena in this machine is accounted by an iterative algorithm, while motion-integrated boundary conditions allow the torque estimation at different positions. The obtained results are further verified and have good agreement with finite element analysis.\u3c/p\u3

Adaptive isogeometric analysis applied to an electromagnetic actuator

In this paper, a magnetostatic solver for linear and nonlinear soft-magnetic material characteristics, a time-harmonic eddy current solver, and the corresponding function-based error estimates are implemented in an established adaptive isogeometric analysis framework. The simplified truncated hierarchical B-spline basis functions are investigated on the multipatch geometry of a magnetic circuit, as they offer several beneficial properties, including a drastic reduction of the number of degrees of freedom compared to the references under uniform refinement. Global error estimate and global parameters convergence are illustrated for different refinement strategies and polynomial orders. Finally, the computational effort is analyzed

Soft-landing control of low-energy solenoid valve actuators

\u3cp\u3eAn automotive, fluid-control solenoid valve is composed of an electromagnetic reluctance actuator and a near-constant-force spring. Its motion profile is characterized by short closed-To-open transition times which demand fast switching, while valve lifetime improves by minimizing the impact velocity, i.e. a soft landing. In this paper, a cascaded position-and current-feedback control is designed and implemented on nonlinear, axisymmetric magnetostatic finite element simulations of a low-energy solenoid valve actuator. By applying the cascaded control, actuator performance is improved considerably, as a soft landing, a timely actuation, and an increased energy-efficient device have been obtained.\u3c/p\u3

Topology comparison of slotless permanent magnet semispherical actuators

This paper presents a comparison of several three-degrees-of-freedom (DoFs) semispherical actuator topologies, which can mimic a shoulder joint of an actuated support system. A semianalytical model is applied to determine the torque performance as function of the position. Hence, the current distribution through the coils with minimized ohmic losses can be determined. The performed topology comparison is based on the average power dissipation and on a set of torque and range of motion requirements