Closed-loop thyristor current control
System- and communication configuring D7-SYS - SIMADYN D
5-55
Edition 06.2002
Connec-
tion
Significance
Value
Value
change
Type
CAV.XF2
Current-dependent inverter stability limit [1] {
≥
0.0
…
0.2
≤
}
Condition: 0.0
≤
XF2
≤
0.2,
> QSF\bit 12 = 1
0.0
Init
CAV.IAV
Correction for the inverter stability limit [1]
{
≥
0.7
…
1.3
≤
}
Condition: 0.7
≤
IAV
≤
1.3,
> QSF\bit 12 = 1
1.0
Init
CAV.AL1
Positive correction of the current actual value sensing
Condition: -0.1
≤
AL1
≤
0.1,
> QSF\bit 12 = 1
0.0
Init
CAV.AL2
Negative correction of the current actual value sensing
Condition: -0.1
≤
AL2
≤
0.1,
> QSF\bit 12 = 1
0.0
Init
CPI.PC
Inhibit integrator component
0
PC6.DZ
Mode: Double firing
0
FCS.IE
Option: Field present
0
5.3.3 Current sensing calibration
The following commissioning steps may only be carried-out when the
system is stationary and the closed-loop control is disabled:
Adjust (calibrate) the V/f converter frequency for the current actual value
sensing:
•
The closed-loop current control remains switched-out.
→
SOL.ION=0 or SOL.IOF=1
•
The offset frequency [kHz] should be read at CAV.YFO = calibration
value for CAV.XFO.
•
The calibration value should be entered at CAV.XFO with the inverse
polarity.
•
The value becomes effective (Initialization mode) after a restart.
The output CAV.YC must have a value which is approximately zero.
The circuit for sensing and frequency conversion has an offset and drifts
with temperature and time. This means that the offset must be checked
again when the system is in a warm operational condition and after a
longer operating time.
In the software there is an option at FB CAV to correct a gain error of the
current actual value sensing.
This adapts the normalization of the actual value.
The value for the correction in the software should be determined using a
separate check of the sensing in the drive converter and is only required
in special cases.
For a SITOR set (e.g. 6QG32x), a check always incurs some time.
The inputs CAV.AL1, .AL2 should be kept at the default value.
Options
Procedure
Note
Correcting gain
errors (optional)
