General Product Information - Unitek BAMOCAR-PG-D3-400/400 Manual

Basic - Information
1.6

General product information

The digital three-phase servo amplifier BAMOCAR-PG-D3-400/400, 700/250, 700/400 forms a 4-quadrant drive
unit together with the motor, driving and braking with energy feedback in both directions of rotation. Depending
on the installed parameter set, the amplifier is suitable for EC synchronous motors, AC asynchronous motors or DC
motors.
The drive concepts are characterised by different advantages and disadvantages.
The EC drive (synchronous motor) has the highest efficiency and the highest power per weight and volume. It is
maintenance-free and has high control dynamics. The disadvantage is the field weakening range, which is difficult
to control, and the high braking torque in the event of a motor short circuit.
The EC synchronous motor (brushless DC motor) in its electrical version is a synchronous motor with permanent
magnet rotor and three-phase stator.
The physical properties correspond to those of the DC motor, i.e. the current is proportional to the torque and the
voltage is proportional to the speed. The speed is controlled stably up to the current limit (max. torque). In case of
overload, the speed decreases at constant current.
Rectangular speed-torque characteristic.
Current, speed and position are measured exactly.
The rotating field frequency is not a controlled variable, it adjusts itself independently.
The motor voltages and motor currents are sinusoidal.
The AC drive (asynchronous motor) has the highest speed range due to the simple field weakening and it does not
generate a braking torque in the event of a motor short circuit. The disadvantage is the size and the poorer
efficiency. The controlled variable is the rotating field frequency, taking into account the motor-specific
parameters (field-oriented control). The motor voltages and motor currents are sinusoidal.
With both three-phase systems, no motor movement takes place if the rotating field is switched off or there is
power stage damage. The heat loss occurs mainly in the motor stator.
The DC drive (direct current motor) has the best synchronisation and a high control range. Emergency operation
can be achieved by directly connecting the battery voltage. Disadvantages are the carbon brushes and the heat
generation in the armature. The drive can rotate at high speed in the event of a power stage failure.
The current is proportional to the torque and the voltage is proportional to the speed.
Current, speed and position (bearing) are measured exactly. The speed is controlled stably up to the current limit
(max. torque). In case of overload, the speed decreases at constant current.
Rectangular speed-torque characteristic.
Field weakening is possible with externally excited motors.
BAMOCAR-PG-D3-xxx can be used as a position controller, torque or speed amplifier. The actual speed value is
generated from the encoder unit (resolver or other) or internally (sensorless). A large control range and high
control dynamics require an encoder system.
Warning / Caution:
For DC, AC and BL servo amplifiers fed from the DC mains, the energy feedback into the DC
link during braking operation must be taken into account.
(External ballast circuit)
Version: 2021 / V2 Page: 5 BAMOCAR-PG-D3-700/250, 400