ABB REG670 - Under Voltage Seal-In

The load angle ArgLd is same in forward and reverse direction, so it is suitable to begin
the calculation of the parameter setting. The parameter is set to the maximum possible
load angle at the maximum active load. A value larger than 20° must be used.
The blinder RLd can be calculated according to the equation
174
min
min
exp max
0.8
U
RLd U
P
= × ×
æ ö
ç ÷
è ø
GUID-AF9BD6F2-E64B-424D-B361-49448A1CF690 V2 EN (Equation 174)
Where,
Pexpmax is the maximum exporting active power
Umin is the minimum voltage for which Pexpmax occurs
0.8 is the security factor to ensure that the setting of RLd can be lesser than the calculated
minimal resistive load
Load encroachment characteristic
ArgLd
ArgLd
ArgLd
ArgLd
RLd-RLd
jX
R
IEC11000304_1_en
IEC11000304 V1 EN
Figure 167: Characteristics of load encroachment in R-X plane
8.9.3.3 Under voltage seal-in
Settings involved in under voltage seal-in are:
Section 8 1MRK 502 071-UEN -
Impedance protection
316 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual