Unitek DS-400.2 Series, Руководство пользователя

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Basic information
5 04/2019 - V01 DS 400.2
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2.7 General product information
The digital 3-phase current servo amplifiers DS/DPC xxx as component (BDM) in combination with
the synchronous servo motor (EC motor) or the asynchronous servo motor (ac motor) provide a
drive solution (PDS) 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.
For synchronous motors the generated heat in the motor only occurs in the stator, the rotor
remains cold. The motors can easily be cooled via the surface (efficiency up to 96%).
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 rotor moment of inertia is notably smaller and the limiting performance is higher which
results in up to 5 times higher acceleration values.
Asynchronous servo motors are less expensive and do not require solenoids in the rotor.
The control characteristics are very good due to the space-vector control, the performance and
the efficiency are lower. Due to the heated rotor it is necessary to use a motor fan for large
control ranges.
The EC and ac motors have the protection rating IP65.
The motor voltages and the motor currents are sinusoidal. A maximum motor efficiency is
achieved by means of a compensating current control.
DS/DPCxx drives can be used as single-axis position amplifiers or torque or speed amplifiers.
The position and speed actual value is generated in the encoder unit (resolver, incremental, or
SIN/COS encoder). The encoder pulses are emitted from the amplifier for a superordinate
PLC/CNC control.
The control circuits of current, speed, and position are PID controllers which are easy to program.
They can be programmed by means of the PC Software NDrive2.
The communication with superordinate controls is effected by means of BUS systems (standard
CAN-BUS, RS232) or by analogue interfaces.
Note:
For dc, ac, or EC servo amplifiers which are supplied by a bus circuit, it must be checked that the
energy is fed back into the bus during brake operation (lift drives, winding machines, great
centrifugal masses).
An internal or possibly external ballast resistor is necessary.