greater magnetic field and increased amount shakes would improve the shake torches ability to light the LED faster by producing more voltage. This was what was hypothesised; from the collected data it is fair to say there is somewhat a relation between the length of the magnets and amount of shakes. The data does support the hypothesis. By doubling the magnets…
Note that all of these motors are entirely circumferential flux type. Motor M1 has a 3mm disk, while the thickness of the only disk of motor M7 is 6mm. Similarly, the thickness of both disks of motor M4 is 3mm, but motor M9 has two 3mm and 6mm disks. The results indicated that the input power, starting torque and power factor of motors with thin disk, i.e., M1 and M7, are greater than those of motors with thick disk, i.e., M4 and M9. In other words, increasing volume of hysteresis material by…
Design and implementation of an Electronic system for identification of rebars in reinforced concrete.
Abstract- In this paper non-destructive method is implemented in which magnetic self-designed sensor is used to detect position of rebar in reinforced concrete. During the renovation of old buildings it is necessary to locate rebar accurately to avoid damages in construction. This is achieved by Magnetic sensor which is made up of E-shaped core also primary and secondary windings. Due to…
When a magnet is in motion near a non-magnetic conductor such as copper and aluminium eddy currents are induced in the conductor, causing a dissipative force called magnetic braking force, or a change in magnetic flux (figure 2). This force is dependent on:
The size and shape of the conductor and magnet
The strength of the magnet (μ)
The conductors conductivity (σ_c)
The distance between the conductive surface and the magnet (d)
The velocity of the magnet (v)
According to Faraday’s law,…
In this part, a survey of existing work and literature relating to the project is covered.
The differences between PM machine and conventional AC machines
Induction machine is also called “asynchronies machine”. The rotor is placed in a rotating magnetic field and thus a rotating force can be attained.
The rotor is a rotating conductor and is mainly produced in cage shape. The stator generates the rotating magnetic field. The rotating of the magnetic field is not achieved…
maintains the magnetic flux and produces a particular value of the flux density B at that point in a magnetic field. Therefore the flux density is the cause while the flux density (B) is the effect. The flux density can be assumed proportionally to the field intensity in a magnetic field which comes in three parts. First part is:
Where U stands for the permeability of force (the measure of the degree to which the magnetic line of force can penetrate the material). The value of magnetic space…
plasma transport processes
5230CvMagnetohydrodynamics (including electron magnetohydrodynamics)
5272+vLaboratory studies of space- and astrophysical-plasma processes
There has been significant recent work on Vlasov-Maxwell (VM) equilibria that are consistent with nonlinear force-free1–8 and “nearly force-free”9 magnetic fields in Cartesian geometry. Therein, force-free refers to…
In essence, Tesla coils are a high-voltage, resonant transformer circuits. They consist of the six major components (Behrend 1), namely:
Figure 1: Tesla coil (diagram)
A primary transformer is a step-up transformer that takes the line voltage of the AC source and steps it up to a range between 12 kV and 50 kV at 60 Hz (Johnson 4). The efficiency of this transformer is largely dependable on the construction…
Motors transform electrical energy to mechanical energy, hence they are essential for energy conversions in electrical machines.
All types of electrical motors are made up of a stationary field referred to a stator and a rotating field referred to a rotor. According to Krishnan, (2010), DC motors operate through the interaction of an electric current with magnetic flux to generate a torque and rotational speed. D.C motors are of different types but they all operate…
there is a whole chapter on the nature of induced forces in magnetic fields. This struck great interest and lead to further research.
In the 1830’s, an English scientist named Michel Faraday was credited with the discovery of induced currents and the practical behind it. He first wrapped a copper wire around an iron ring. On one side of the ring, there was a battery with a switch. On the opposite side, there was a galvanometer. He noticed a strange pattern in variations in currents. This…