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This article is the first work to carefully investigate the characteristics of iron loss per weight and relative permeability between the flake and spherical powders with a sinusoidal excitation up to a high frequency of 3.5 MHz in experiments using three separate measurement systems. The composition of the considered powder samples contains 0.001 wt% C, 0.012 wt% Si, 0.09 wt% Mn, 0.0004 wt% P, 0.008 wt% S, and 0.06 wt% O. The flake particle has the preferred orientation that the easy axes are normal to the platelet face, and the water atomized iron powder was processed with ball milling with the lubrication. Key objectives of the utilization of the three independent measurement systems with different specialized equipment and probes are to cross-check and overcome unexpected measurement errors of the related devices in use for validating measured results thoroughly. Experimental results demonstrate the much better performances on the iron loss per weight and relative permeability of the flake powder than that of the spherical powder at high frequencies. Physics-based explanations for the measured results are also presented. Furthermore, two estimation functions based on a six-parameter Steinmetz equation for the measured iron loss of the powders are developed by using MATLAB. [ABSTRACT FROM AUTHOR]

In this paper, we develop and examine permanent magnet synchronous motors (PMSMs) by use of both stator and rotor cores made of nanocrystalline magnetic materials (NMMs). We report core loss properties of the PMSM with the NMM under inverter excitation. In addition, we compare core losses of the PMSM with conventional non-oriented (NO) steel sheets under inverter excitation to discuss the core loss characteristics of the NMM motor. In average, under inverter excitation, the reduction ratio in core loss of the PMSM made of NMM is about 60% as compared with the core loss of the PMSM with NO sheets. In particular, the average decrease obtained by using NMM rotor core instead of NO rotor core is about 30%. [ABSTRACT FROM AUTHOR]

We calculate an iron loss attributed to semiconductors ON-voltages in an inverter circuit and reveal influence rate of the ON-voltages on whole iron loss. In our previous work, it has been revealed by inverter excitation that the ON-voltages make minor loops in magnetic hysteresis of magnetic material and the loops affect iron loss characteristics. In this paper, it is investigated by a factor analysis how much the on-voltage has an influence on iron loss, quantitatively. We separate whole iron loss caused in a non-oriented electrical steel sheet into three losses: loss by the ON-voltage, loss by fundamental component, and loss by inverter carrier. The rates of these losses are evaluated under several conditions of single-phase pulse width modulation inverter excitation, and the results show that the proportion of loss by ON-voltages is up to around 10% depending on inverter excitation parameter: fundamental frequency, carrier frequency, modulation index, and magnetic flux density. [ABSTRACT FROM PUBLISHER]

This paper presents the results of experimental trials carried out on a permanent magnet synchronous motor (PMSM) that uses a stator core made of a nanocrystalline magnetic material (FINEMET). It is demonstrated that the manufactured stator can reduce the PMSM total iron loss by 64% to 75% compared with an equivalent motor using a stator made of conventional non-oriented silicon steel. The experimental results are confirmed by 2-D finite-element analysis. [ABSTRACT FROM AUTHOR]

SUMMARY In this study, it is demonstrated that the iron loss from the SiC-MOSFET, which represents a new power semiconductor with an extremely low on-voltage for electric machine drives, is almost the same as that from an Si-IGBT, which is a conventional power semiconductor. In order to evaluate the iron loss characteristics when an SiC device is used, two single-phase pulse width modulation inverters were built and used for the excitation of a ring made up of electrical steel sheet. One of the inverter employed an SiC-MOSFET, and the other inverter employed an Si-IGBT. The iron losses for the two inverters are compared. [ABSTRACT FROM AUTHOR]

It is revealed by magnetic field analysis that a difference between an actual reactor loss and a material datasheet loss, which was observed by measurement using an actual reactor with air gaps under high-frequency excitation, is caused by leakage magnetic flux near the air gaps of a reactor. In our previous measurement, an actual reactor loss under high-frequency excitation became large compared with a datasheet loss of the reactor core material. To clarify the reason, we carry out a 3-D magnetic field analysis. As a result, due to the increasing eddy current losses by leakage magnetic flux density near reactor gaps and due to the ununiform distributions of an iron loss caused by leakage magnetic flux, the reactor loss becomes larger than that of the datasheet loss. [ABSTRACT FROM AUTHOR]

The iron losses of a reactor with an air gap are investigated and compared for three different magnetic materials, namely, grain-oriented material (GO230), high performance non-oriented Fe-Si metal (super E ST125), and nanocrystalline soft magnetic material (FINEMET FT-3M). The iron losses of the reactor are measured by the experiments for different voltage supply frequencies and amplitudes. The measured data are compared with the material iron losses that are calculated from the manufacturer’s material datasheets. It is concluded that the air gap is responsible for a large part of the increase between the reactor and material iron losses and that the FT-3M has sensibly higher building factor compared with the other materials. [ABSTRACT FROM AUTHOR]

We describe a method to analyze the effects of shrink fitting and stamping on the mechanical stress distribution and iron loss in motor cores. Shrink fitting and stamping are important processes in manufacture of motor cores from electrical steel. The mechanical stress distribution is evaluated by a structural finite-element method, and the iron loss is evaluated by combined analysis of the electromagnetic field (by a finite-element method) and mechanical stress. The method clearly shows that the iron loss becomes larger as the width of the shrink fit increases, an effect borne out by experiment. In regard to the effect of stamping, calculation results again agree well with experimental data. [ABSTRACT FROM AUTHOR]