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Split-ring resonator is a unit which enhances magnetic permeability and magnetic coupling for metamaterials. Split-ring connector is a ring shaped type of timber connector that is in inserted in routed grooves between timber members in order to reduce stresses to the timbers at the connection points. Commutator (electric), also called split rings.
The split ring resonator was a microstructure design featured in the paper by Pendry et al in 1999 called, "Magnetism from Conductors and Enhanced Nonlinear Phenomena". [11] It proposed that the split ring resonator design, built out of nonmagnetic material, could enhance the magnetic activity unseen in natural materials.
The resistance of the commutator contacts causes inefficiency in low-voltage, high-current machines such as this, requiring a huge elaborate commutator. This machine generated 7 volts at 310 amps. Although direct current motors and dynamos once dominated industry, the disadvantages of the commutator have caused a decline in the use of ...
The commutator is zero if and only if a and b commute. In linear algebra, if two endomorphisms of a space are represented by commuting matrices in terms of one basis, then they are so represented in terms of every basis. By using the commutator as a Lie bracket, every associative algebra can be turned into a Lie algebra.
Some other names used for slip ring are collector ring, rotary electrical contact and electrical slip ring. Some people also use the term commutator; however, commutators are somewhat different and are specialized for use on DC motors and generators. While commutators are segmented, slip rings are continuous, and the terms are not interchangeable.
Compared to a squirrel-cage rotor, the rotor of the slip ring motor has more winding turns; the induced voltage is then higher, and the current lower, than for a squirrel-cage rotor. During the start-up a typical rotor has 3 poles connected to the slip ring. Each pole is wired in series with a variable power resistor.
The commutator assembly on a large motor is a costly element, requiring precision assembly of many parts. On small motors, the commutator is usually permanently integrated into the rotor, so replacing it usually requires replacing the rotor. While most commutators are cylindrical, some are flat, segmented discs mounted on an insulator.
In a motor, the magnitude of this Lorentz force (a vector represented by the green arrow), and thus the output torque, is a function for rotor angle, leading to a phenomenon known as torque ripple) Since this is a two-pole motor, the commutator consists of a split ring, so that the current reverses each half turn ( 180 degrees).