Identification of the eddy current method features in the implementation of computer simulation algorithms for controlling the characteristics of the food production equipment parts

2019 ◽  
Vol 1 (97) ◽  
pp. 31-40
Author(s):  
N.M. Zashchepkina ◽  
V.G. Zdorenko ◽  
V. Sebko ◽  
O.M. Markina
Keyword(s):  
Magnetic Field ◽  
Computer Simulation ◽  
Eddy Current ◽  
Current Transformer ◽  
Geometrical Parameters ◽  
Parameter Control ◽  
Contact Method ◽  
Transformer Transducer ◽  
Simulation Algorithms ◽  
The Magnetic Field

Purpose: The purpose of this article is to study the theoretical provisions of the operation of a vortex device in the implementation of a non-contact method of controlling the details of brewing equipment using computer simulation algorithms. Design/methodology/approach: The theoretical positions of thermal ECT operation with a copper product are obtained, which is controlled while maintaining a constant value of the magnetic field frequency f1 = 70.0 Hz, with small values of the generalized parameter x≤1.1 and increasing the parameter x due to the increase in the frequency of thermal ECT, that is, at x≥3.5. Findings: On the basis of computer simulation algorithms the results of the joint measuring control of diameter d, electrical resistance ρ and temperature t of the sample made of copper (in the temperature range from 20-160°C) and the results of determination of thermally dependent thermal ECT signals with the sample of equipment details and the values of specific normalized values that relate the ECT signals to the physical and mechanical characteristics of the samples of the equipment being monitored. Research limitations/implications: Product diameters range is 5 mm to 50 mm. The lower boundary is limited by the frequency of the magnetic field f = 20 Hz and the upper boundary by the diameter of the frame of the thermal eddy current transformer transducer is 50 mm. Perspective positions of work require further development in the direction of extending the limits of control of geometrical parameters of the samples due to the use of automated control systems based on overhead eddy current transformer transducers. Practical implications: The practical value of the work is to increase the overall likelihood of control of the parameters of brewing equipment parts by increasing its instrumental component Di, due to the reduction of measurement errors due to instrumental techniques and on the basis of computer modelling algorithms for three-parameter control of parts of brewing equipment, electrical and temperature parameters, allows to obtain the value of the overall control probability Dz = 0.998. Originality/value: The originality of the article is the study of the theoretical provisions of the eddy current transformer transducer and the implementation of a non-contact method of controlling the details of brewing equipment using computer simulation algorithms that take into account the modes of joint three-parameter control: at high values of the generalized parameter x (with three-parameter surface control), at small values of x (while controlling the value of the average cross section geometry, electrical, temperature settings) at a fixed frequency magnetic field (get information on the diameter d, resistivity ρ and temperature t with a certain depth of penetration of the magnetic field in the sample Δ).

scholarly journals STUDY OF CONDUCTIVE MATERIALS BY MEANS OF A MULTI-FREQUENCY MEASUREMENT SYSTEM BASED ON MICROMINIATURE EDDY CURRENT TRANSFORMERS

Dependability ◽  
2017 ◽  
Vol 17 (4) ◽  
pp. 49-52
Author(s):  
S. F. Dmitriev ◽  
A. V. Ishkov ◽  
A. O. Katasonov ◽  
V. N. Malikov ◽  
A. M. Sagalakov
Keyword(s):  
Magnetic Field ◽  
Eddy Current ◽  
Measurement System ◽  
Distinctive Feature ◽  
Current Transformer ◽  
Eddy Current Method ◽  
The Core ◽  
Useful Signal ◽  
The Magnetic Field ◽  
Excitation Winding

A measurement system has been developed that is based on an eddy current transformer and allows evaluating the applicability of the eddy current method for detecting local defects of products made of an aluminium-magnesium alloy. The paper describes the design of a microminiature eddy current transformer (ECT) with an excitation, measurement and compensation windings that uses a pyramidal core that enables localization of the magnetic field within an area about 2500 square мm. The distinctive feature of the measurement system consists in the ability to detect deep defects (up to 5 mm). The paper sets forth the primary parameters of the transformer that enable the magnetic field localization (shape, material and size of the core, number of the windings and number of loops). It also describes the process of preparation and application of several ECTs with different core and winding parameters. That allowed the ETCs generating different electromagnetic fields and reacting to the changes in that field with varied efficiency. Optimal ECT size for identifying defects in aluminium-magnesium alloys was established (pyramidal shape of the core, base 400 мm in diagonal, edge 4 mm long, 20 loops of the excitation winding, 200 loops of the measurement winding, 200±40 loops of the compensation winding). The paper describes the design of the measurement system and the measurement method that allows finding defects with the linear size of 0.25 mm situated 5 mm below the surface or more depending on the signal received from the eddy current transformer. The measurement system includes two microminiature transformers controlled by special C++ software. Voltage to the excitation winding was applied by an integrated rectangular wave generator. This setup allowed creating a magnetic field with minimal noise. The voltage of the excitation winding varied from 2 to 3V. The transformers output signal was processed in a hardware filtering system described in this paper. The distinctive feature of the measurement system is the synchronous change of the measurement signal generation frequency and filtration frequency. That enables efficient extraction of the useful signal that carries information on the defects of the tested object. The paper sets forth data that demonstrate the dependence of the amplitude part of the signal from the defects of various sizes and experimentally establishes the limit defect sizes under which such measurements are possible. The research covered objects in the form of aluminium-magnesium plates (94% Al, 3% Mg). Amplitude changes due to the linear sizes of the defects and the depth of their situation. The nature of such changes allows identifying the defects’ parameters. Depending on the size and depth of the defects, the change of the amplitude associated with the transformer passing above the defect were from 2.5V (for a defect 0.25 mm wide situated 1 mm from the surface) to 0.1V (for a defect 0.25 mm wide situated 5 mm from the surface).

STUDY OF PHASE PROPAGATION IN SUPERCONDUCTING ALUMINUM BY ULTRASONIC ATTENUATION MEASUREMENTS

1959 ◽  
Vol 37 (5) ◽  
pp. 614-618 ◽  
Author(s):  
K. L. Chopra ◽  
T. S. Hutchison
Keyword(s):  
Magnetic Field ◽  
Eddy Current ◽  
Ultrasonic Attenuation ◽  
Cylindrical Specimen ◽  
Current Theory ◽  
Superconducting Phase ◽  
Rate Of Change ◽  
Time Rate ◽  
Phase Propagation ◽  
The Magnetic Field

The phase propagation in superconducting aluminum has been studied by measuring the time rate of change of ultrasonic attenuation. The time taken for the destruction of the superconducting phase in a cylindrical specimen, by means of a magnetic field, H, greater than the critical field, Hc, is approximately proportional to{H/(H–Hc)} in agreement with eddy-current theory. In the converse case, where the superconducting phase is restored by switching off the magnetic field H (>Hc), the total time taken is nearly independent of the temperature (or Hc) as well as H. The superconducting phase grows at a non-uniform volume rate which is considerably less than the uniform rate of collapse.

Quantitative Research on Cracks in Pipe Based on Magnetic Field Response Method of Eddy Current Testing

2021 ◽  
Vol 36 (1) ◽  
pp. 99-107
Author(s):  
Feng Jiang ◽  
Shulin Liu ◽  
Li Tao
Keyword(s):  
Magnetic Field ◽  
Eddy Current ◽  
Quantitative Research ◽  
Three Dimensional ◽  
Impedance Analysis ◽  
Eddy Current Testing ◽  
Element Analysis ◽  
Defect Parameter ◽  
Current Testing ◽  
The Magnetic Field

The quantitative evaluation of defects in eddy current testing is of great significance. Impedance analysis, as a traditional method, is adopted to determine defects in the conductor, however, it is not able to depict the shape, size and location of defects quantitatively. In order to obtain more obvious characteristic quantities and improve the ability of eddy current testing to detect defects, the study of cracks in metal pipes is carried out by utilizing the analysis method of three-dimensional magnetic field in present paper. The magnetic field components in the space near the crack are calculated numerically by using finite element analysis. The simulation results confirm that the monitoring of the crack change can be achieved by measuring the magnetic field at the arrangement positions. Besides, the quantitative relationships between the shape, length of the crack and the magnetic field components around the metal pipe are obtained. The results show that the axial and radial magnetic induction intensities are affected more significantly by the cross-section area of the crack. Bz demonstrates obvious advantages in analyzing quantitatively crack circumference length. Therefore, the response signal in the three-dimensional direction of the magnetic field gets to intuitively reflect the change of the defect parameter, which proves the effectiveness and practicability of this method.

Design of TSV-based Inductors for Internet of Things

2016 ◽  
Vol 2016 (DPC) ◽  
pp. 002111-002130 ◽  
Author(s):  
Bruce C Kim ◽  
Saikat Mondal
Keyword(s):  
Magnetic Field ◽  
Internet Of Things ◽  
Power Electronics ◽  
Eddy Current ◽  
Electronics Packaging ◽  
High Density ◽  
Metal Core ◽  
The Core ◽  
Iot Applications ◽  
The Magnetic Field

This paper describes the design of a Through Silicon Via based high density 3D inductors for Internet of Things (IoT) applications. We present some possible challenges for TSV-based inductors in IoT applications. The current trend towards Internet of Things (IOT), System in Package (SiP) and Package-on-Package (PoP) requires meeting the power requirements of heterogeneous technologies while maintaining minimum package size. 3-D chip stacking has emerged as one of the potential solutions due to its high density integration in a 3D power electronics packaging regime. As an integral part of many power electronics applications, TSV-based inductors are becoming a popular choice because of their high inductance density due to the reduced on-chip footprint compared to conventional planar inductors. Depending on the requirement, values of these inductors could range from a few nanohenries to hundreds of microhenries. Small inductors with a high quality factor are mainly used for RF filter applications, whereas large inductors are used in power electronics packaging. For high inductance it is necessary to use ferromagnetic materials. A conventional ferromagnetic metal core like nickel could offer high permeability, which can help to boost the inductance. However, the magnetic field lines within a metal core induce eddy current which can have multiple adverse effect in power electronics packaging. For example, it has long been known that the current can increase the resistance in transformer winding [1]. Eddy current can also heat up the core of the inductor which makes the heat sink process in 3D packaging even more challenging. One way to decrease the eddy current, is to pattern and laminate the core block into multiple segments orthogonal to the direction of the magnetic field line [2]. Another method is to increase the resistivity of the core material so that the eddy current is limited to a very small magnitude [3].

scholarly journals A fast forward solution with a boundary element method for eddy current nondestructive testing

2002 ◽  
Vol 15 (2) ◽  
pp. 205-216
Author(s):  
Hermann Uhlmann ◽  
Olaf Michelsson
Keyword(s):  
Magnetic Field ◽  
Boundary Element Method ◽  
Boundary Element ◽  
Eddy Current ◽  
Eddy Currents ◽  
Order Approximation ◽  
Approximation Schemes ◽  
Constant Field ◽  
The Magnetic Field ◽  
Element Method

Eddy current non-destructive testing is used to determine position and size of cracks or other defects in conducting materials. The presence of a crack normal to the excited eddy currents distorts the magnetic field; so for the identification of defects a very accurate and fast 3D-computation of the magnetic field is necessary. A computation scheme for 3D quasistatic electromagnetic fields by means of the Boundary Element Method is presented. Although the use of constant field approximations on boundary elements is the easiest way, it often provides an insufficient accuracy. This can be overcome by higher order approximation schemes. The numerical results are compared against some analytically solvable arrangements.

Analysis and Experimental Evaluation of Inherent Instability in Electromagnetic Eddy-Current Dampers Intended for Reducing Lateral Vibration of Rotating Machinery

1995 ◽  
Author(s):  
Yuri Kligerman ◽  
Asif Grushkevich ◽  
Mark S. Darlow ◽  
Adrian Zuckerberger
Keyword(s):  
Magnetic Field ◽  
Eddy Current ◽  
High Speed ◽  
Experimental Tests ◽  
Rotating Machinery ◽  
Lateral Vibration ◽  
Negative Effect ◽  
Eddy Current Damper ◽  
Analytical Approaches ◽  
The Magnetic Field

Abstract There have been a number of papers published that concern the design and operation of electromagnetic, eddy-current dampers for controlling lateral vibration of rotating machinery. Many of these papers have included analysis approaches and all have been generally effective for low-speed operations. There have been a few reports concerning high-speed (supercritical) operations and many of these have indicated instability problems, but none of these have provided a valid analysis to account for instability. That is, all of the analytical approaches have ignored the disk rotation, relative to the magnetic field, and no obvious sources of instability have been found. In this paper, we will present our work in which we have rederived the analyses of this system in which we have not made the common assumption of no rotation between the disk and the magnetic field. In this case, the potential of instability for supercritical speed operation is clear and, in fact, the equivalent negative damping contribution of the eddy-current damper, under these conditions, has a negative effect on the system even if not fully unstable. We have carefully performed a series of experimental tests which corroborate this analytical approach. Finally, we briefly discuss alternative eddy-current damper design approaches that could be considered to provide effective damping at all speeds and avoid these instability problems.

Zum normalen Skin-Effekt unter Berücksichtigung der magnetischen Widerstandsänderung

1964 ◽  
Vol 19 (11) ◽  
pp. 1273-1276
Author(s):  
Rudolf Klein
Keyword(s):  
Magnetic Field ◽  
Field Dependence ◽  
Eddy Current ◽  
Magnetic Field Dependence ◽  
Skin Effect ◽  
Normal Skin ◽  
Maximum Value ◽  
High Fields ◽  
The Magnetic Field ◽  
Normal Skin Effect

The penetration of a magnetic field into an infinite metallic half-space is altered due to the presence of the magnetoresistance of the medium. MAXWELL’S equations modified by the magnetic field dependence of the conductivity are solved for the case where the field at the surface is switched on immediately and is constant afterwards. It is shown that due to magnetoresistance the field runs into the medium quicker compared to the case of the pure normal skin effect. The induced eddy current has its maximum value no longer at the surface of the specimen. The results are discussed in connection with pulse methods for the measurement of magnetoresistance in high fields.

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