scholarly journals Saturated single phase magnetic circuit under sinusoidal voltage: Iron losses - definition of a new physical concept - equivalent schemes

2021 ◽  
Vol 125 ◽  
pp. 106381
Author(s):  
J.F. Brudny
Keyword(s):  
Single Phase ◽  
Magnetic Circuit ◽  
Sinusoidal Voltage ◽  
Physical Concept ◽  
Iron Losses ◽  
Definition Of

The Concept of the Individual and Its Scope

2018 ◽  
Author(s):  
Ursula Renz
Keyword(s):  
Strict Sense ◽  
Physical Concept ◽  
Individual Group ◽  
Group Minds ◽  
Definition Of ◽  
The Individual

This chapter discusses the implications of Spinoza’s concept of individual bodies, as introduced in the definition of individuum in the physical digression. It begins by showing that this definition allows for an extremely wide application of the term; accordingly, very different sorts of physical entities can be described as Spinozistic individuals. Given the quite distinct use of the terms divisibilis and indivisibilis in his metaphysics, however, the chapter argues that the physical concept of individuality is not universally applied in the Ethics but reserved for physical or natural-philosophical considerations. The chapter concludes with a discussion of the problem of collective individuals. It is argued that, while societies or states are described as individual bodies, they do not constitute individual group minds in the strict sense of the term for Spinoza. This in turn indicates that minds are not individuated in the same way as bodies.

scholarly journals Modular Rotor Single Phase Field Excited Flux Switching Machine with Non-Overlapped Windings

Energies ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1576 ◽  
Author(s):  
Lutf Ur Rahman ◽  
Faisal Khan ◽  
Muhammad Afzal Khan ◽  
Naseer Ahmad ◽  
Hamid Ali Khan ◽  
...  
Keyword(s):  
Phase Field ◽  
Single Phase ◽  
Dead Zone ◽  
Optimization Technique ◽  
Rotor Design ◽  
Iron Losses ◽  
Excitation Coil ◽  
Electromagnetic Performance ◽  
Copper Losses ◽  
Single Phase Field

This paper aims to propose and compare three new structures of single-phase field excited flux switching machine for pedestal fan application. Conventional six-slot/three-pole salient rotor design has better performance in terms of torque, whilst also having a higher back-EMF and unbalanced electromagnetic forces. Due to the alignment position of the rotor pole with stator teeth, the salient rotor design could not generate torque (called dead zone torque). A new structure having sub-part rotor design has the capability to eliminate dead zone torque. Both the conventional eight-slot/four-pole sub-part rotor design and six-slot/three-pole salient rotor design have an overlapped winding arrangement between armature coil and field excitation coil that depicts high copper losses as well as results in increased size of motor. Additionally, a field excited flux switching machine with a salient structure of the rotor has high flux strength in the stator-core that has considerable impact on high iron losses. Therefore, a novel topology in terms of modular rotor of single-phase field excited flux switching machine with eight-slot/six-pole configuration is proposed, which enable non-overlap arrangement between armature coil and FEC winding that facilitates reduction in the copper losses. The proposed modular rotor design acquires reduced iron losses as well as reduced active rotor mass comparatively to conventional rotor design. It is very persuasive to analyze the range of speed for these rotors to avoid cracks and deformation, the maximum tensile strength (can be measured with principal stress in research) of the rotor analysis is conducted using JMAG. A deterministic optimization technique is implemented to enhance the electromagnetic performance of eight-slot/six-pole modular rotor design. The electromagnetic performance of the conventional sub-part rotor design, doubly salient rotor design, and proposed novel-modular rotor design is analyzed by 3D-finite element analysis (3D-FEA), including flux linkage, flux distribution, flux strength, back-EMF, cogging torque, torque characteristics, iron losses, and efficiency.

scholarly journals Single-phase linear actuator with semi-closed magnetic circuit.

1988 ◽  
Vol 108 (8) ◽  
pp. 749-756 ◽  
Author(s):  
Tsutomu Maeda ◽  
Hiroshi Fujita ◽  
Hitoshi Hamazaki
Keyword(s):  
Single Phase ◽  
Magnetic Circuit ◽  
Linear Actuator ◽  
Closed Magnetic Circuit

The Poynting Vector and the New Theory of a Transformer. Part 11. Three-Phase Three-Core Transformers without a Neutral Wire

2021 ◽  
Vol 1 (1) ◽  
pp. 23-34
Author(s):  
Mansur A. SHAKIROV ◽  
Keyword(s):  
Equivalent Circuit ◽  
Single Phase ◽  
Poynting Vector ◽  
Magnetic Circuit ◽  
Phase Zone ◽  
Field Patterns ◽  
Three Phase ◽  
Short Circuits ◽  
The Difference ◽  
Mathematical Relations

A topological equivalent circuit for a three-phase three-core transformer reflecting the spatial structure of its magnetic system is developed. Owing to this approach, it became possible to represent the magnetic fluxes of the magnetic circuit’s all main sections and the apertures for each of three phases directly in the circuit in the absence of the windings’ neutral wires. The circuit is constructed by stitching together the anatomical circuit models of single-phase transformers obtained in the previous parts with taking into account the relationships between the fluxes at the junctions of the phase zones in iron. Its validity is confirmed by the rigor nature of the physical and mathematical relations for idealized transformers with infinite magnetic permeability of iron and simplified magnetic field patterns, which corresponds to the generally accepted approach with neglecting the magnetization currents. The difference lies in the fact that the developed model takes into account the heterogeneity of magnetization in different parts of the magnetic circuit with allocating more than 30 sections in the iron and apertures. The transition to the model of a real three-core transformer is carried out by adding four nonlinear transverse magnetization branches in each extreme phase zone and eight branches in the central phase zone to the idealized equivalent circuit. It is shown that in cases of winding connections without neutral wires, there is no flux of the Poynting vector in interphase zones in any unbalanced mode. In this case, the problems connected with the occurrence of fluxes exceeding the no-load fluxes under the conditions of symmetric and asymmetric short circuits, as well as the occurrence of buckling fluxes in these modes in the region outside the transformer iron, are solved.

Determination of Magnetic Losses in a Transformer by Wattmetric Method

2020 ◽  
Vol 63 (5) ◽  
pp. 27-31
Author(s):  
Sergey Plotnikov ◽  
Keyword(s):  
Single Phase ◽  
Magnetic Circuit ◽  
Dynamic Measurement ◽  
Frequency Error ◽  
Magnetic Losses ◽  
Empirical Knowledge ◽  
The Magnetic Field ◽  
Good Agreement ◽  
Three Components

The purpose of the article is to describe the methodology for determining the components of losses in the magnetic circuit of a transformer. Based on current empirical knowledge about the extent to which each of the three components of the losses in the steel of the magnetic circuit depends on the frequency of the magnetic field, a wattmetric method for determining these losses has been developed. The method consists in measuring the total losses in the magnetic circuit at three frequencies using the idle experience and calculating the three components of the losses. It does not matter to what extent each component depends on the amplitude of mag-netic induction or other parameters. It has been established that it is advisable to carry out idling experiments in the range of 50 ... 70 Hz, in which there is no dynamic measurement error, and the frequency error of the coefficients of the calculated matrix is negligible. The results obtained for a single-phase transformer are in good agreement with modern ideas about the ratio of the three components of the losses in the magnetic circuit.

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