Siemens SINAMICS PERFECT HARMONY GH180 Function Manual page 132

Parameter Assignment/Addressing
6.8 Options for Stability Menu (3) - first half
This process magnifies offsets and noise that are introduced by the measurements. In order to
limit the gain at extremely low frequencies, the transfer function is approximated by 1/(s + a),
where a is the S/W compensator pole. The pole introduced by a affects the motor flux phase
angle, and is chosen to be low enough such that the error introduced is small.
In typical applications that have short cables between the motor and the VFD the default value of
a, 2 rad/s, provides a good compromise between flux phase angle error and reduced gain at dc.
In long cable applications, the effect of compensating the cable voltage drop, resistive and
inductive, causes additional terms to be introduced in the motor flux calculation, i.e. V
– I*R
measurement errors. However, there is an adverse effect on the starting torque capability.
Typically for cables longer than 5000 m, a can be set in the range of 4 to 6 rad/s. With such a
setting, enable High starting torque mode (2960) to maintain good starting torque capability.
Table 6-54 Flux Control Menu (3100) Parameters
Parameter ID
Flux reg prop gain 3110
Flux reg integral 3120
gain
Flux filter time const 3130
Flux table menu 3131
Note: To be re‐
leased in a later
software version.
Flux demand 3150
Note: To be re‐
leased in a later
software version.
Flux ramp rate 3160
Note: To be re‐
leased in a later
software version.
Energy saver min 3170
flux
Flux droop 3195
130
– I*w*L . This requires that a be increased so as to avoid the sensitivity of offsets and
cable cable
Unit Default
1.72
1.0
sec 0.0667
Submenu
pu 1.0
sec 0.5
% 100.0
% 0
Min Max Description
0.0 10.0 Flux PI regulator proportional gain term.
0.0 1200.0 Flux PI regulator integral gain term.
0.0 10.0 Time constant of the low pass filter used on the
flux error.
Flux shaping table parameters
0.16 10.0 Set the flux demand, or desired V/Hz ratio. Use the
default setting to set the V/Hz ratio to nameplate
values.
0.0 5.0 Set the ramp time to go from zero to rated flux.
This time establishes the time to magnetize the
motor.
10.0 125.0 Set the lowest value of flux, as a percentage of
rated motor flux that the drive will apply to an
unloaded motor.
Energy Saver is enabled if you enter a value that is
less than the flux demand. The control establishes
the amount of flux or motor voltage that minimi‐
zes the losses in the motor.
0 200 Set flux droop for parallel drives, to keep the volt‐
age balanced between drives. This parameter is
used for fine adjustments on flux droop with the
main reference coming from an external PLC. Re‐
fer to Section Parallel Drive Control for a single IM.
= V
motor
NXGPro+ Control Manual
Operating Manual, A5E50491925A
vfd