The stator electrical
unbalance fault is simulated through the insertion of resistors between the frequency converter and the PMSM input (Fig.
In order to verify the decoupling performance between the motor speed, rotor flux-linkage, and two displacement components, the influence of rotor
unbalance vibration is temporarily ignored; the given values of related variables are suddenly changed at different times: the given rotor flux-linkage is reduced from 0.95 Wb to 0.5 Wb at 0.5 s; the given motor speed is increased to 3000r/min from 1500r/min at 0.75 s; the given [alpha] displacement is increased to 0.03 mm from 0.0 mm at 1.0 s and recovered to 0.0 mm at 1.2 s; the given [beta] displacement is increased to 0.03 mm from 0.0 mm at 1.4 s and recovered to 0.0 mm at 1.6 s; a 10N.m load torque is suddenly added at 1.5 s.
In the paper, we focus on analyzing
unbalance compensation for Multi-Input Multi-Output (MIMO) AMB system using the frequency-domain approach based ILC controller.
As the spindle structure is compact, the noncontact exciting force and the additional
unbalance force are applied on the same position of the shaft end.
A generalized computer program would be in order for determining an optimal design by degree of
unbalance and further for dealing with user-created designs.
Forces that show up at the spindle frequency include
unbalance forces and the force of each tooth slicing away a "chip" of material.
* Monitor and detect voltage
unbalance. Three-phase motors operated on unbalanced voltages will overheat; many overload relays can't sense the overheating.
In the July 2005 "Tooling Around" column, we looked at the calculation of balance as applied to rotating tool assemblies using the balance standard ISO 1940-1, and the amount of force that results from just a small amount of
unbalance. (See the Archives link at Tooling & Production's website: www.toolingandproduction.com.) This month we'll look more closely at how the force from
unbalance compares to what happens during the cutting process.
Electrical performance offers typical insertion loss of 0.25 dB, isolation of 20 dB minimum, VSWR of 1.10 typical, phase
unbalance of 2[degrees] maximum and amplitude
unbalance of 0.2 dB maximum.
Frequency (or spectral) analysis is the most common method used for detecting machine faults such as rotor
unbalance, shaft misalignment, mechanical looseness, and bearing damage.
The huge unbalancing vibration of crankshaft system may be aroused by the
unbalance mass of crankshaft system, which can destroy the running stability of diesel engine and then deteriorate the wear condition among the movement units.
The asymmetry of the active-reactive load elements, both in symmetric and asymmetric under voltage leads to
unbalance current.
