Rotating Magnetic Field


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Related to Rotating Magnetic Field: Nikola Tesla, Induction motor

Rotating Magnetic Field

 

a magnetic field that arises as a resultant field during the superimposition of two or more alternating magnetic fields of identical frequency but spatially displaced in phase with respect to one another. The phenomenon of a rotating magnetic field, which was first described in strict scientific form in 1888 independently and virtually simultaneously by the Italian physicist G. Ferraris and the Serbian engineer N. Tesla, is used in electric motors, measuring instruments, and various AC regulation and control equipment. In most cases the rotating magnetic field in an electrical machine is induced by a three-phase current that feeds three coils (1, 2, and 3 in Figure 1) whose axes are displaced 120° in space. A two-phase rotating magnetic field is used mainly in small induction motors and electrical measurement devices. The direction of rotation of a rotating magnetic field depends upon the phase order of a multiphase system and the relative orientation of the coil axes in space.

Figure 1. Formation of a rotating magnetic field upon superimposition of three sinusoidal magnetic fields that are displaced 120° spatially and with respect to phase: t denotes the pole pitch; B1,, B2, and B3 are magnetic inductions created by the currents of the first, second, and third phases; and B is the total magnetic induction of the rotating field.

REFERENCES

Kalantarov, P. L., and L. R. Neiman. Teoriia tsepei peremennogo toka, 4th ed. Moscow-Leningrad, 1954. (Teoreticheskie osnovy elektrotekhniki, part 2.)
Veselovskii, O. N. Mikhail Osipovich Dolivo-Dobrovol’skii [1862-1919]. Moscow-Leningrad, 1958.
References in periodicals archive ?
Here, to analyze a wide range of problems of the electromagnetic nature an effective base is the multiposition numerical calculations of rotating magnetic fields allowing to form temporal functions of the considered quantities.
In order to calculate the relative magnitudes of the asynchronous motor torques under different rotor slips, under current frequency [f.sub.1] i [not equal to] [f.sub.1n] and supply voltage [U.sub.1] i [not equal to] [not equal to] [U.sub.1] n, the i-th speed of the rotating magnetic field is determined at first
The modeling results are rotating magnetic field which the magnetic flux values depends on relative active zone diameter [D.sub.a]/D.
The requests to the rotating magnetic field inductor are different in the process activating units used for different purposes.
Zahn, "Heating in the MRI environment due to superparamagnetic fluid suspensions in a rotating magnetic field," Journal of Magnetism and Magnetic Materials, vol.
For example, the nano-rotor was able to spin a full 360 degrees in about one second with continuously controlled motion driven by a rotating magnetic field. The nano-hinge was able to be closed or opened in 0.4 seconds, or held at a specific angle with a precision of eight degrees.
Among the topics are oxidation induced copper coating on a steel surface, the influence of materials ratio on the hydration process of magnesium oxychloride cement, the effect of solute atoms on the thermal property of magnesium alloys, refining the grain of pure aluminum by inoculation and a rotating magnetic field, manufacturing aluminum foam without a thickening agent with melt foaming method and in compressive behavior, first-principles calculations of hydrogen isotope effects on uranium hydrides, and characterizing crack initiation life in ferromagnetic material by metal magnetic memory testing.
In this section we give the analytical solution of (13) for a rotating magnetic field. The first term, representing the Larmor torque, spoils the separation of Cartesian components, which has enabled the derivation of the solution, equation (11), found in Section 2 for the Debye relaxation equation.
Using a rotating magnetic field, the researchers were able to fabricate the ideal textured microstructure of the individual LiCoO2 grains making up the cathode: a perpendicular alignment of the c-plane (the vertical side) and a random orientation of the c-axis.
The flipping is said to produce a sheet of current that is a sprawling surface extending from the sun's equator where the rotating magnetic field induces an electrical current into the solar system.
A rotating magnetic field in the stator is created by the applied ac power.
They were found by suspending nasal cells in a solution and moving them using a rotating magnetic field. The cells were then separated off and examined in more detail.

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