Unitek BAMOCAR-PG-D3-700-900, Manual

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Basic - information
Version: 2020 / V3 Seite: 5 BAMOCAR-PG-D3-700-900
1.6 General product information
The digital 3-phase current servo amplifiers BAMOCAR-PG-D3-700-900 in combination with the motor provide a 4-
quadrant drive which can be used in both rotation directions for drive operations and brake operations with
energy feed-back. According to the installed parameter components the amplifiers are suitable for EC synchronous
motors, ac asynchronous motors, or dc motors.
The individual drive versions have different advantages and disadvantages.
The EC drive (synchronous motors) has the highest efficiency and performance per weight and volume and
provides a drive solution free of maintenance and with a wide dynamic control range. However, the high braking
torque in case of motor short-circuits is a disadvantage and it is also difficult to control the field weakening range.
From the electrical view, the EC synchronous motor (brushless dc motor) is a synchronous 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 proportional to the torque and
the voltage is proportional to the speed. The speed is steadily controlled up to the current limit (max. torque). In
case of an overload the speed drops and the current remains constant.
The speed/torque characteristic is rectangular.
Current, speed, and position are precisely measured. The field frequency is not controllable, it is automatically
adjusted.
The motor voltages and the motor currents are sinusoidal.
The ac drive (asynchronous motors) has the widest speed range due to the single field weakening and there is no
braking torque in case of a motor circuit. However, the unit size and the worse efficiency is a disadvantage. The
rotating field frequency can be controlled in due consideration of the motor specific parameters (field-based
control). The motor voltages and motor currents are sinusoidal.
With both 3-phase current systems there will be no motor movement neither when the rotating field is switched
off nor in case of an output stage damage. Most of the heat losses are generated in the motor stator.
The dc drive (dc motor) has the most uniform running and a wide control range. It is possible to provide an
emergency operation by directly connecting the battery voltage. The carbon brushes and the heat development in
the armature are disadvantages. The drive may run at high speed in case of an output stage damage.
The current is proportional to the torque and the voltage is proportional to the speed.
Current, speed, and position are precisely measured. The speed is steadily controlled up to the current limit (max.
torque). In case of an overload the speed drops and the current remains constant. The speed/torque characteristic
is rectangular. Field weakening might occur with separately excited motors.
The BAMOCAR-PG-D3-700-900 can be used as position amplifier or torque or speed amplifier.
The speed actual value is generated in the encoder unit (resolver or others) or internally generated (without
sensors). It is necessary to provide an encoder system for wide control ranges and high control dynamics.
Warning/Attention:
For dc, ac, or bl-servo amplifiers which are supplied via the dc mains, it must be
checked that the energy is fed back into the bus during brake operation.
(External ballast circuit)