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Transistor Servo-Drive TVD6-200bl, TVD6.2-400bl
General Information
The transistor 3-phase current servo amplifier SERVO-TVD6 and TVD6.2 in combination
with the brushless dc motor (synchro servo motor, CE motor) provide a drive solution
free of maintenance and with a wide dynamic control range. The drive displays the
well-known good control characteristics of dc drives without the disadvantages of the
carbon brushes’ wear and the commutation limits. The rotor moment of inertia is nota-
bly lower and the limit power is greater than with equally constructed dc motors. This
results in up to 5 times higher acceleration values. The generated heat in the motor
only occurs in the stator, therefore, the bl-motors always have the protection rating IP
65.
From the electrical view, the brushless dc motor is a synchro motor with a permanent
magnet rotor and a three-phase current stator.
The physical characteristics correspond to those of dc motors, i.e., the current is propor-
tional to the torque and the voltage is proportional to the speed. Current and voltage
are precisely measured, thus the analog circuits are simply constructed.
It is possible to control the speed via the motor voltage, however, in order to achieve
the best control precision, a tacho control is always used. The speed actual value is ge-
nerated in the encoder unit (rotor position encoder plus brushless tacho).
The difference of the command value and the actual value is amplified in the speed
control loop circuit (P-I-controller) of the servo drive. This results in the current com-
mand value, which is transferred to the three phase-current controllers by means of the
rotor position signal. In the course of this the stator magnetic field leads the rotor mag-
netic field by 90° electrically.
This field frequency is not controllable, it is automatically adjusted.
The motor currents are trapezoidal.
For dc, ac, or bl-servo amplifiers which are supplied by a dc bus, it must be checked
that the energy is fed back into the bus during brake operation (winding machines, lifts,
great centrifugal masses).
The ballast circuitry is rated for 3% duty cycle. An extended operating time can be
achieved by additional external resistors.
Information:
For motors with incremental encoder UNITEK TVD3-2-xx-IN
with resolver UNITEK TVD3-2-xx-RS
with bl-tacho UNITEK TVD3-2-xx-bl
For low-voltage applications UNITEK TVD3-230-xx-bl
UNITEK TVD3-230-xx-IN
UNITEK TVD3-230-xx-RS
For high power UNITEK TVD6-2 -bl,IN,RS
200V/400V up to 25/40A
For digital servo controllers UNITEK DS400
200V/400V up to 50/100A
General Information