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ELECTRICAL SPECIFICATIONS |
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1.
ALTERNATOR The auxiliary windings on the stator of the main machine G1, feeds brushless exciter machine's G2 stator via a control element of automatic voltage regulator G3. The generated voltage generated by the exciter rotor is rectified by silicon diode bridge and DC is supplied to the main machine's G1 rotor. In load changes, the voltage stabilization of the main machine is obtained automatically by voltage regulator by changing exciting current.
2.
VOLTAGE AND FREQUENCY Alternators
are produced up to 695V according to VDE 0530 and international
standards. Our standard application is 400 V-50 Hz. Different voltage
and frequency can be applied if it is required. 3.
VOLTAGE REGULATOR This
is the most important element of the synchronized alternator. At
unsymmetrical loads, the voltage regulator senses three phases as a
reference so maximum voltage asymmetry is 6%. Electrical and
thermical tests are applied before mounting the alternator. The output
voltage could be adjusted manually by a potentiometer within ±5% or ±10%
tolerance of rated voltage. To remotely regulate the voltage there are
terminals for potentiometer connection. 4.
STATIC VOLTAGE DROP Static
tolerance iş ±%1.5 of the nominal voltage under the following
conditions: -In
constant loads between no-load to nominal load At
cos phi=0.8 to 1 -irrespective
of temperature involved -at
a speed drop of 3% 5.
DYNAMIC VOLTAGE DROP The
magnetic circuit and windings are designed for minimum dynamic voltage
drop in sudden load changes. At sudden load changes, the time required
to regain the rated voltage is between 0.2 to 0.4 sec. When rated load
is applied at cos phi=0.8, the transient voltage drop is less than 15%. 6.
OVERLOAD The
alternators are designed to withstand a 110% load for one hour in 6 hour
work period to conform the overload capacity of internal combustion
engines. A load of 150% can be withstood for a period of 2 minutes
according to VDE 0530.. 7.
WAVEFORM The
waveform of the output voltage between phases is sinusoidal. In
accordance with VDE 0530, the maximum deviation from sine form is less
than 5% between unloaded phases. The distortion of the harmonic content
of the voltage is less than 3%. 8.
SHORT CIRCUIT CURRENT Sudden
short circuit current is kept as low as possible by selecting the
appropriate parameters. Sustained short circuit current is 2,5 - 4 times
of the rated current. 9.
RADIO INTERFERENCE SUPPRESSION Standard
alternators have grade N interference suppression according to VDE
0875. If requested, K degree is applicable. |
