Power / kVA resp. kW
Time / s
S
lim
=100
P
lim
=80
P
fb
=60
WMaxLimPct =40
10
20
30
40
50
60
70
Gradient = -600 % S
lim
/min
Fig. 32:
Power gradient according to sample parameters and calculation
The following formulae are used to calculate the Q filter parameter and cos-phi gradient:
Fig. 33:
Formula for calculating the Q filter parameter
Fig. 34:
Formula for calculating the cos-phi gradient (internal power gradient)
10.2.2
Voltage-dependent power reduction P(U)
If it is not possible to compensate adequately for increase in voltage in the upstream distribution network by intake on re-
active power, it may be necessary to curtail the active power. In this case, P(U) control is available for making optimum
use of the capacity of the upstream grid.
P(U) control reduces the active power that is fed in as a function of the grid voltage using a prescribed characteristic curve
as a basis. P(U) control is implemented as an absolute power limit. The actual power of the inverter may vary freely below
this limit due to a possible fluctuation in the available power or the target value, but at no time increases above the abso-
lute power limit.
Page 58] and [See figure 36] [
Page 58] are two examples of configuration. In figure 1 without hys-
teresis, the function is activated as soon as the voltage exceeds the configured voltage of data point 1 (dp1). The power
limit follows the characteristic curve, a straight line between dp1 and dp2. The function is deactivated as soon as the
voltage falls below dp1. In [See figure 36] [
Page 58], the function is activated as soon as the voltage exceeds the con-
figured voltage of dp2. In this case, dp1 does not result in activation of the function because the power limit remains at
100%. The power limit follows the characteristic curve, a straight line between dp2 and dp3. However, because hysteresis
is activated, the power limit is not increased when the voltage drops. The function is deactivated as soon as the voltage
falls below dp1.
Voltage
P
/
Pref
dp
1
dp
2
Fig. 35:
Example characteristic curve without hysteresis
P
/
Pref
dp
1
dp
3
dp
2
Voltage
Fig. 36:
Example characteristic curve with hysteresis and a
deactivation threshold below the activation threshold
In the case of storage inverters, the function is only available in discharge/grid feed-in mode, not in battery charging
mode.
KACO blueplanet gridsave 50.0TL3-S
Page 58
EN
