Unitek TVD6.2-RS, Руководство пользователя

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Transistor-Servo-Drive TVD6.2-RS
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The transistor 3-phase current servo amplifier
SERVO-TVD6
.
2
forms toget-
her with the brushless direct current motor (synchro-servo (EC-) motor) a
propulsion unit distinguished by its rear-zero maintenance and by its high
dynamic control range.
The drive displays the wellknown good regulation characteristics of the
direct current drives without the disadvantages of the carbon brush wear
and of the communication limits.
The rotor intertia is notably lower and the power envelope is greater
than with equally constructed DC-motors. The result are up to 5 times
higher acceleration values. As the generated heat in the motor occurs in
the stator, the ec-motors are always designed to the protection standard IP
65.
The brushless direct current motor is electrically a synchro-motor with a
permanent magnet rotor and 3-phase stator.
The physical characteristics correspond to those of the direct current
motors, that is, the current is proportional to the torque and the voltage is
proportional to the speed. As both values can be measured precisely, the
servo-control unit can be mounted easily. It is possible to control the speed
from the motor voltage, but in order to achieve exact regulation it is prefe-
rable touse atways a tachometer regulation.
The tachometer actual value is generated from the sensor unit (resolver).
In the speed controller (P-I-controller) of the servo-drive is the differenz of
nominal value and actual value amplified. The result is the current nomi-
nal value, which is transferred by the resolver signal onto the three phase
current controllers such that the stator magnetic field leads ca. 90° electri-
cally the rotor magnetic field.
This field frequency is not a controlled variable, it adjusts istself automati-
cally. The motor currents, following the resolver interpretation, form a si-
ne-waved rotating field.
As occurs in all DC-, AC or ec-servo-amplifiers which are supplied by the
dc-bus, the feed-back of the energy must be observed when braking in the
dc-bus (especially where stroke or eccentric cycles are concerned). The
bleeder switch is set for a 3 % duty cycle. The ballast-resistors have to be
mounted externally.
Information:
For lower power >>> UNITEK Serie TVD3.2
100V upto 10/20A
For higher power >>> UNITEK Serie MODULA
400V upto 100/200A
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