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Currents due to shaft voltage causes deterioration of motor bearings, but can be prevented with a grounding brush on the shaft, grounding of the motor frame, insulation of the bearing supports, or shielding. Shaft voltage can be induced by non-symmetrical magnetic fields of the motor (or generator) itself.
In an electric power system, automatic generation control (AGC) is a system for adjusting the power output of multiple generators at different power plants, in response to changes in the load. Since a power grid requires that generation and load closely balance moment by moment, frequent adjustments to the output of generators are necessary.
These will absorb a part of the vibrations (and the noise) produced by the machines. To control the electromagnetic vibrations at the origin, skewing the electric motor or choosing a better slot/pole combination [3] will reduce electromagnetic force harmonics or avoid resonances between magnetic forces and structural modes of the electric motor.
Torsional vibration is a concern in the crankshafts of internal combustion engines because it could break the crankshaft itself; shear-off the flywheel; or cause driven belts, gears and attached components to fail, especially when the frequency of the vibration matches the torsional resonant frequency of the crankshaft. Causes of the torsional ...
Capability curve of an electrical generator describes the limits of the active and reactive power that the generator can provide. The curve represents a boundary of all operating points in the MW/MVAr plane; it is typically drawn with the real power on the horizontal axis, and, for the synchronous generator , resembles a letter D in shape, thus ...
Rotordynamics (or rotor dynamics) is a specialized branch of applied mechanics concerned with the behavior and diagnosis of rotating structures. It is commonly used to analyze the behavior of structures ranging from jet engines and steam turbines to auto engines and computer disk storage.
Simple hydraulic control valves are binary, they are either on or off. Servo valves are different in that they can continuously vary the flow they supply from zero up to their rated maximum flow, or until the output pressure reaches the supplied pressure. More complex servo valves can control other parameters.
The motor provides the power, turning the generator at a constant speed, and the signal to be amplified is applied to the generator's field winding. The higher the current applied to the winding, the stronger the magnetic field and thus the higher the output voltage of the generator. So the output voltage of the generator is an amplified copy ...