Challenges in high and low field AC magnetic measurements for material modelling and electrical machine performance prediction

2006 ◽  
Author(s):  
T. Moses
Keyword(s):  
Performance Prediction ◽  
Magnetic Measurements ◽  
Electrical Machine ◽  
Material Modelling ◽  
Machine Performance ◽  
Low Field

scholarly journals High-temperature thermomagnetic properties of vivianite nodules, Lake El'gygytgyn, Northeast Russia

2013 ◽  
Vol 9 (1) ◽  
pp. 433-446 ◽  
Author(s):  
P. S. Minyuk ◽  
T. V. Subbotnikova ◽  
L. L. Brown ◽  
K. J. Murdock
Keyword(s):  
Magnetic Susceptibility ◽  
High Temperature ◽  
Magnetic Measurements ◽  
Iron Phosphate ◽  
Northeastern Russia ◽  
Northeast Russia ◽  
Low Field ◽  
Lake El’Gygytgyn ◽  
Monoclinic Pyrrhotite ◽  
Thermomagnetic Properties

Abstract. Vivianite, a hydrated iron phosphate, is abundant in sediments of Lake El'gygytgyn, located in the Anadyr Mountains of central Chukotka, northeastern Russia (67°30′ N, 172°05′ E). Magnetic measurements, including mass-specific low-field AC magnetic susceptibility, field-dependent magnetic susceptibility, hysteresis parameters, temperature dependence of the induced magnetization, as well as susceptibility in different heating media, provide ample information on vivianite nodules. Electron microprobe analyses, electron microscopy and energy dispersive spectroscopy were used to identify diagnostic minerals. Vivianite nodules are abundant in both sediments of cold (anoxic) and warm (oxic) stages. Magnetic susceptibility of the nodules varies from 0.78 × 10−6 m3 kg−1 to 1.72 × 10−6 m3 kg−1 (average = 1.05 × 10−6 m3 kg−1) and is higher than the susceptibility of sediments from the cold intervals. Magnetic properties of vivianite are due to the respective product of oxidation as well as sediment and mineral inclusions. Three types of curves for high-temperature dependent susceptibility of vivianite indicate different degrees of oxidation and inclusions in the nodules. Vivianite acts as a reductant and reduces hematite to magnetite and masks the goethite–hematite transition during heating. Heating vivianite and sulfur mixtures stimulates the formation of monoclinic pyrrhotite. An additive of arsenic inhibits the formation of magnetite prior to its Curie temperature. Heating selective vivianite and pyrite mixtures leads to formation of several different minerals – magnetite, monoclinic pyrrhotite, and hexagonal pyrrhotite, and makes it difficult to interpret the thermomagnetic curves.

scholarly journals Efficiency Improvement of Switched Reluctance Generator Using Optimization Techniques

2017 ◽  
Vol 2 (1) ◽  
pp. 74 ◽  
Author(s):  
Márcio Rodrigues da Cunha Reis ◽  
Wanderson Rainer Hilário De Araújo ◽  
Wesley Pacheco Calixto
Keyword(s):  
Power Converter ◽  
Optimization Techniques ◽  
Electrical Machine ◽  
Efficiency Improvement ◽  
Switched Reluctance Machine ◽  
Switched Reluctance ◽  
Machine Performance ◽  
Reluctance Machine ◽  
Several Variables ◽  
Maximum Value

This article introduces the switched reluctance machine operating as a generator. This kind of electrical machine delivers CC power at the output and the energy generated can be controlled through several variables. In this work, the switching angles of the machine's power converter are optimized using deterministic and heuristic techniques so that the output power is kept constant via PI controller while guaranteeing maximum value for machine performance, even for different excitation values and mechanical power on the shaft.

scholarly journals Performance Assessment of Axial-Flux Permanent Magnet Motors from a Manual Manufacturing Process

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 2122
Author(s):  
Adrian Mlot ◽  
Juan González
Keyword(s):  
Permanent Magnet ◽  
Manufacturing Process ◽  
Permanent Magnet Synchronous Motor ◽  
Electrical Machine ◽  
Assembly Process ◽  
Permanent Magnet Motors ◽  
Axial Flux ◽  
Element Analysis ◽  
Machine Performance ◽  
Electric Traction

Implementation of a new design for the process of assembling an axial-flux permanent magnet synchronous motor (AF PMSM) may lead to unstable motor parameters during operation at low and high speeds. In this paper, experimental data related to the AFPMSM used in an electric traction motor was monitored. The paper presents tracing of machine performance in order to find quality-related issues and to evaluate the assembly process. To assess the manual manufacturing process (low-volume production) and electrical machine performance, several motors, characterized by the same size and topology, were extensively tested. Useful AF PMSM parameters such as continuous torque and continuous current were measured. The winding temperature of the stators was also monitored and carefully examined. An attempt to assess motor performance, based on measurements and aimed at the identification of the weakest parts of the electric motor design is presented. In this paper it can be seen how the subcomponents of the machine and its detailed assembly process and tolerances play key roles in achievement of the designed continuous performance with symmetrical temperature distribution in the stator winding. Selected conclusions drawn from the obtained measurements were explained by a rotor/stator misalignment study using 3-D finite element analysis.

Electrical- Magnetic Transport and Magnetoresistance in La 0.7 Ca 0.3 MnO3/BN Composites

2011 ◽  
Vol 228-229 ◽  
pp. 379-384
Author(s):  
Yong Dan Zhu ◽  
Hong Hua Liao ◽  
Jian Jun Tan ◽  
An You Zuo ◽  
Jin Qiao Yi ◽  
...  
Keyword(s):  
Magnetic Measurements ◽  
Solid State Reaction Method ◽  
Boundary Region ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Low Field ◽  
Maximum Value ◽  
Spin Polarized ◽  
Magnetic Transport ◽  
Lower Temperature

The electrical–magnetic transport properties of (La0.7Ca0.3MnO3)(1-x)/(BN)x composites has been investigated systemically by conventional solid-state reaction method. The results of X-ray diffraction (XRD) and scanning electronic microscopy (SEM) show that BN and LCMO coexist in the composites and BN mainly goes into the grain boundary region without any chemical reaction with La0.7Ca0.3MnO3, which are in accordance with the results of the magnetic measurements. It is very interesting that with increasing of BN content level (x < 0.25), the metal–insulator transition temperature (TP) remains constant (nearly at 275K), and the resistivity increases very slowly. But when x > 0.25, TP shifts to lower temperature and the resistivity increases dramatically. The resistivity threshold of the composites occurred at x = 0.25, and specially the magnetoresistance (MR) reaches a maximum value (about 26.32 %) at 100K in an applied magnetic field of 3kOe. The results also indicate that the doped BN has an important effect on the low field MR (LFMR), which results from spin-polarized tunneling.

Ultra-Low-Field Squid Magnetic Measurements on High Temperature Ceramic YBaCuO Superconductors

1987 ◽  
Vol 99 ◽  
Author(s):  
D. C. Cronemeyer ◽  
A. P. Malozemoff ◽  
T. R. Mcguire
Keyword(s):  
High Temperature ◽  
Transition Temperature ◽  
Ceramic Sample ◽  
Superconducting Transition Temperature ◽  
Magnetic Measurements ◽  
Zero Field ◽  
Superconducting Transition ◽  
Temperature Range ◽  
Low Field ◽  
The Difference

ABSTRACTWe report ultra-low-field (5 mOe - 1 Oe) magnetic measurements on a ceramic sample of YBaCuO. A positive remanent moment is observed which accurately equals the difference of the field-cooled and zero-field-cooled moments throughout the temperature range. At higher fields this relationship breaks down. A reversible region is observed near the superconducting transition temperature which is independent of field. These results are discussed in the context of recent models.

Introduction of an Integrated Turbo-Electrical Machine

2017 ◽  
Author(s):  
Sebastian Schuster ◽  
Christian Kreischer ◽  
Dieter Brillert
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Small Mass ◽  
High Mass ◽  
Electrical Machine ◽  
Flow Area ◽  
Machine Performance ◽  
High Fluid ◽  
Compact Design

Turbomachines are commonly designed for a high mass flow rate. However, because of new cycle concepts, turbomachines are also required to compress or expand at small mass flow rates. One example is the supercritical carbon dioxide Brayton cycle. The mass flow rate can be in the range of one kg/s at an almost high fluid density at the inlet to the compressor. This results in a small through flow area. In this paper, a turbomachine concept is presented that integrates the turbomachine parts into an electrical machine. Specifically, the turbomachine is located in the gap between the rotor and the stator of the electrical machine. In that way, a very compact design can be achieved. This paper aims to explain the basic concept. An aerodynamic design study is performed that demonstrates the important parameters for machine performance. Additionally, the design of the electrical machine is discussed based on a realistic application. Finally, conclusions for further development are drawn.

Low field magnetic measurements of high temperature superconductors

1989 ◽  
Author(s):  
G. Shaw ◽  
S.D. Murphy ◽  
Z.-Y. Li ◽  
A.M. Stewart ◽  
S.M. Bhagat
Keyword(s):  
High Temperature ◽  
Magnetic Measurements ◽  
High Temperature Superconductors ◽  
Low Field
Sign in / Sign up

Export Citation Format

Share Document