NOTICE
Motor identification must be carried out before activating the DC quantity control in the overmodulation range.
p3856[0...n]
Compound braking current / Compound I_brake
CUG120XA_USS
(Compound brake)
Access level: 3
Calculated: -
Data type: FloatingPoint32
Can be changed: T, U
Scaling: PERCENT
Dynamic index: DDS, p0180
Unit group: -
Unit selection: -
Function diagram: -
Min:
0.00 [%]
Max:
250.00 [%]
Factory setting:
0.00 [%]
Description:
Compound braking current is used to define the amount of DC current that is produced on stopping the motor during
U/f operation to further increase the DC braking function.
Compound braking is a superimposition of the DC braking function with regenerative braking (net braking along the
ramp) after OFF1 or OFF3. This permits braking with controlled motor frequency and minimum power input into the
motor.
Effective braking without using additional hardware components is obtained by optimizing the ramp down time and
compound braking.
Dependency:
The compound braking current is only activated if the DC link voltage exceeds the threshold value in r1282.
Compound braking does not operate in the following cases:
- DC braking activated (p1230, r1239).
- motor is still not magnetized (e.g. for flying restart).
- vector control parameterized (p1300 >= 20).
- synchronous motor used (p0300 = 2xx).
NOTICE
Generally, increasing the braking current improves the braking effect when stopping the motor. However, if the value
is set too high, then the drive can be tripped (shut down) as a result of overcurrent or ground fault.
Recommendation: p3856 < 100 % x (r0209 - r0331) / p0305 / 2
Compound braking generates a current in the motor with a ripple manifesting the rotational frequency. The higher the
braking current is set, the higher the resulting ripple, especially when the Vdc_max control is simultaneously active
(refer to p1280).
Note
The parameter value is entered relative to the rated motor current (p0305).
Compound braking is deactivated with p3856 = 0%.
p3857[0...n]
DC quantity controller P gain / DC_ctrl Kp
Access level: 3
Calculated: CALC_MOD_CON Data type: FloatingPoint32
Can be changed: T, U
Scaling: -
Dynamic index: DDS, p0180
Unit group: -
Unit selection: -
Function diagram: 6797
Min:
0.000
Max:
100000.000
Factory setting:
0.000
Description:
Sets the proportional gain of the DC quantity controller for the overmodulation range.
p3858[0...n]
DC quantity controller integral time / DC_ctrl Tn
Access level: 3
Calculated: CALC_MOD_CON Data type: FloatingPoint32
Can be changed: T, U
Scaling: -
Dynamic index: DDS, p0180
Unit group: -
Unit selection: -
Function diagram: 6797
Min:
0.00 [ms]
Max:
1000.00 [ms]
Factory setting:
2.00 [ms]
Description:
Sets the integral time for the DC quantity controller.
Parameters
7.3 Parameters
SINAMICS G120XA converter
652
Operating Instructions, 03/2019, FW V1.0, A5E44751205B AB
Summary of Contents for SINAMICS G120XA
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