abc 2000 Series User Manual page 116

limit
Acce l eration time
C0.07
Setting Range
Deceleration time
C0.08
Setting Range
In torque control, the difference between the motor output torque
and the load torque determines the speed change rate of the motor
and load. The motor rotational speed may change quickly and this
will result in noise or too large mechanical stress. The setting of
acceleration/deceleration time in torque control makes the motor
rotational speed change smoothly.
However, in applications requiring rapid torque response, set
the acceleration/deceleration time in torque control to O.OOs. For
example, two AC drives are connected to drive the same load. To
balance the load allocation, set one AC drive as master in speed
control and the other as slave in torque control. The slave receives
the master's output torque as the torque command and must follow
the master rapidly. In this case, the acceleration/deceleration time of
the slave in torque control is set to O.Os.
Group C5: Control Optimization Parameters
PWM sw1tchover
C5.00 frequency upper
Sett
This parameter is valid only for V/F control.
It is used to determine the wave modulation mode in V/F control of
a.synchronous motor.
If the frequency is lower than the value of this parameter, the
waveform is 7-segment continuous modulation. If the frequency is
higher than the value of this parameter, the waveform is 5-segment
intermittent modulation.
The 7-segment continuous modulation causes more loss to
switches of the AC drive but smaller current ripple. The 5-segment
intermittent modulation causes less loss to switches of the AC drive
but larger current ripple. This may lead to motor running instability at
high frequency. Do not modify this parameter generally.
For instability of V/F control, refer to parameter P4. 1 1 . For loss to
AC drive and temperature rise, refer to parameter P0.17.
torque control
in
in
limit
n
in g Ra ge
Detailed Function
Default
control Default
12.00Hz
Default
0.00Hz-15Hz
I
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