Abstract Based on the theory of electromagnetic field, Marine heavy oil induction heater uses principle to realize energy conversion and transfer, so as heat inlet temperature achieve purpose heating.By means induction, eddy currents are generated tubing wall under action a magnetic field. The heated pipe conducts in pipe. In this heating mode, coil is directly around supply unit pipeline ship ...

The purpose of this paper is to review recent research on the applications of existing non-destructive testing (NDT) techniques, especially radio frequency (RF) NDT, for carbon-fibre reinforced plastics (CFRP) composites. Electromagnetic properties of CFRP composites that are associated with RF NDT are discussed first. The anisotropic characteristic of the conductivity and the relationship betw...

A former radioactive waste disposal site is surveyed with two non-intrusive geophysical techniques, including magnetic gradiometry and electromagnetic induction. Data were gathered over the site by towing the geophysical equipment mounted to a non-electrically conductive and non-magnetic fibre-glass cart. Magnetic gradiometry, which detects the location of ferromagnetic material, including iron...

rom the detection of buried treasure to the detection of landmines and unexploded ordnance, the history of metal detectors is long and varied. This article reviews the basic technology for detecting metal objects using electromagnetic induction techniques. Working with the U.S. Army Night Vision and Electronic Sensors Directorate and other government agencies, APL has developed a number of adva...

A closed-form solution of the electromagnetic field equations for a three-phase squirrel-cage induction motor is presented. The analysis starts from the application of the Galilean transformation to Maxwell equations for moving media at constant speed. The induction motor is modelled as five concentric cylindrical layers representing the different construction components of the motor. By solvin...

Introduction Electromagnetic induction (EMI) sensors have a long history of success in finding visually obscured metal objects [1]. Over the past decade, metal detector technology has improved resulting in increased detection rates. These improvements have also increased detection of unwanted items such as nails, bullets, shrapnel and other conductive battlefield debris. Advanced EMI sensors ty...

In this paper the dynamic behavior of linear induction motor is described by a mathematical model taking into account the end effects and the core losses. The need for such a model rises due to the complexity of linear induction motors electromagnetic field theory. The end affects by introducing speed dependent scale factor to the magnetizing inductance and series resistance in the d-axis equiv...

Abstract Geo-electromagnetic forward modeling problems are ill-posed due to the low signal frequencies being used and electrically insulating air space. To overcome this numerical issue, $A - \phi $ formula using magnetic vector potentials ($\bf A$) electric scalar ($\phi $) was developed. At present, there two sets of formulae used: one has a curl–curl ($\nabla \times \nabla structure another ...

Analysis of broken rotor bars in large induction motors Projeto acadêmico sem fins lucrativos desenvolvido no âmbito da iniciativa Acesso Aberto Artigos 407 A new technique to detect broken rotor bars, in large squirrel-cage induction motors is presented. In order to avoid problems in industrial applications, the electromagnetic behavior of induction machines with rotor faults was examined, by ...

The paper deals with the application of the Extended Kalman Filter and the Extended Luenberger Observer algorithms for the stator and rotor fault detection of the induction motor fed by PWM inverter. The induction motor conditions are analyzed using estimated rotor and stator-winding resistance. Mathematical models of the extended state estimators are presented, in which the stator and rotor re...