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Electric vehicles, especially cars, have been in the spotlight for some time now. In the focus of environmentalists, engineers, users, media, etc. With the growth and advancement of the market for such vehicles, other electric vehicles are also focussing on. One of such vehicles is boats, particularly smaller boats up to 8-10 meters in length. Of course, the biggest problem here is charging. The general idea is to use battery modules that can be easily carried and enable hot swapping. This paper investigates scenarios and simulations of the control system for hot swapping of the battery module. Simulations of connection of two and three battery modules to parallel operation and current control are presented in this paper, as well as applied control rules. [ABSTRACT FROM AUTHOR]

This paper presents a torque analysis of an axial flux permanent magnet synchronous machine (AFPMSM) based on analytical analysis of magnetic field. The proposed method for torque analysis requires less computational time and is more flexible than finite element method (FEM). This is important advantage, especially for the early stages of the design process. Torque measurements on prototype AFPMSM confirm the validity of the torque analysis method. Index Terms--Electric machines, magnetic fields, permanent magnet machines, synchronous machines, torque.

The paper presents a finite-element method-based design and analysis of interior permanent magnet synchronous motor with flux barriers (IPMSMFB). Various parameters of IPMSMFB rotor structure were taken into account at determination of a suitable rotor construction. On the basis of FEM analysis the rotor of IPMSMFB with three-flux barriers was built. Output torque capability and flux weakening performance of IPMSMFB were compared with performances of conventional interior permanent magnet synchronous motor (IPMSM), having the same rotor geometrical dimensions and the same stator construction. The predicted performance of conventional IPMSM and IPMSMFB was confirmed with the measurements over a wide-speed range of constant output power operation. Index Terms--Constant power speed range, flux weakening, interior permanent magnet motors, synchronous motors.

The performance comparison of three- and single-phase line-start interior permanent magnet synchronous motors (LSIPMSMs) and induction motors (IMs) with equal squirrel-cage design and symmetric four-pole stator windings is presented. The finite element method was employed in analysis of steady-state synchronous performance of LSIPMSMs. A magnetically linear lumped parameter model was employed in analysis of line-starting performance of LSIPMSMs, where the electrical and also the mechanical subsystems were considered. The procedure which was used for the LSIPMSM design was validated by comparison of calculation and measurement results. The performance of three- and single-phase LSIPMSMs and IMs with equal squirrel-cage design was directly compared and evaluated, thus emphasizing impacts of the permanent magnet breaking torque and reluctance breaking torque on the LSIPMSM performance in the asynchronous operation region. Index Terms--Computer aided design, induction motors, permanent magnet motors, squirrel cage motors, synchronous motors.

The line-starting performance and synchronization capability of a line-start interior permanent magnet synchronous motor (LSIPMSM) has to be evaluated by considering different loads and different values of supply voltages, which requires the usage of a reliable dynamic model. In this work the parameters of a magnetically linear lumped parameter LSIPMSM dynamic model were determined by the differential evolution (DE). The optimization objective was the best possible agreement between the measured and by the model calculated time-behavior of model variables. Parameters determined by the DE are used in the LSIPMSM dynamic model, improving agreement between measured and calculated responses of currents and motor speed. Index Terms--Modeling, optimization methods, parameter estimation, permanent magnet motors, squirrel cage motors.

This paper presents the analytical analysis of magnetic field and back electromotive force (back EMF) calculation in an axial flux permanent magnet synchronous generator (AFPMSG) without stator core. For the verification, the numerical analysis [finite element method (FEM)] of magnetic field is accomplished and comparison between analytical and numerical solution of magnetic field is presented. Both analytical and numerical solutions are obtained via magnetic vector potential, respectively. This paper also presents the comparison between analytical solution and numerical (FEM) solution of back EMF using Faraday's law. The verifications show that good agreement between analytical and numerical solution of magnetic field and back EMF is obtained. The validity of the proposed analytical method is additionally confirmed with measurements of back EMF on prototype AFPMSG with coreless stator. Index Terms--Electric machines, finite element methods, magnetic fields, permanent magnet generators, synchronous generators.

The article deals with designing rotor disks of a double-sided axial flux permanent magnet machine, based on their deflection, due to the pull forces between opposite rotor disks, caused by the permanent magnets. Permanent magnets cause the magnetic flux density to flow between the permanent magnets on opposite rotor disks and its size determines the size of the pull force. That is why it is essential to determine the size of the axial component of magnetic flux density in the middle of the clearance between opposite rotor disks (fictitious air gap) in order to calculate the deflection of the rotor disks. The article presents a new method for determining the size of the axial component of magnetic flux density, based on a simplified finite element method and an approximation method as well as modified equations for determining the deflection of rotor disks. The method is used to determine the pull forces between rotor disks and based on the deflection of the disks an optimum rotor disk thickness can be selected in order to reduce the weight of the machine. [ABSTRACT FROM AUTHOR]

The design optimization of an axial flux permanent magnet synchronous machine with a coreless stator and double external rotor is accomplished by using evolutionary optimization with a genetic algorithm and an analytical evaluation of objective functions. On the basis of eight variable geometry parameters, five objective functions are optimized in order to determine the maximum volume torque density and weight torque density, the minimum volume and weight of permanent magnets per Newton–meter, and the minimum machine price per Newton–meter. Based on the geometric parameters for minimum machine price per Newton–meter, a prototype is built for the rated torque. Optimized and analytically evaluated machine characteristics are validated with a finite-element method (FEM) and the measurements of a prototype. Evolutionary optimization with the analytical evaluation of objective functions significantly shortens the computational time required for design optimization in comparison with the FEM. [ABSTRACT FROM PUBLISHER]

The paper presents a new rotary actuator design—the double rotor permanent magnet synchronous machine (DRPMSM), which is to be used in hybrid electric vehicles (HEVs) as a four-quadrant drive system. The focus in this paper is placed on the electromagnetic design, construction and the experimental validation of the proposed DRPMSM. In contrast to other, this work evaluates the radial-radial electric machine concept with one permanent magnet per pole on the outer rotor. Because of the newly proposed outer rotor design, special attention has been given to investigation of the most appropriate stator-slot/outer-rotor pole/inner-rotor-slot number combination. The DRPMSM performance with six different slot-pole-slot combinations was evaluated based on postprocessing of results from time-stepping finite element analyses (FEA). It was elaborated that the combination 36-8-36 was the most appropriate. It is distinguished by low harmonic distortion in the back electromotive force, high average torque with low ripple, and low iron loss as well. A machine prototype based on the 36-8-36 design has been manufactured and rigorously tested in generator and motor operation. [ABSTRACT FROM AUTHOR]