Woodward HighPROtec MCDLV4, Manual

Page: 973 / 1275

Protective Elements
General application notes on setting the LVRT
The LVRT menu comprises among other things the following parameters:
•
By means of » Vstart«, the LVRT will be started (triggered).
•
By menas of » Vrecover« the LVRT will detect the end of the disturbance.
•
Please note, that the » Vrecover« should be greater than »Vstart«. If this is not the case, the internal
plausibility supervision will set » Vrecover« to 103% of »Vstart«.
•
»Vk«, »tk« are the set points for setting the LVRT-profile.
Special application notes on setting the LVRT-profile
•
In many cases not all available setpoints are needed in order to build up the
LVRT-profile.
•
In case that not all available setpoints are used, the unused setpoints can be set to the same values as the
last set point.
•
Set points should be selected in a manner of left-to-right with time begin at t=0 (tk+1>tk).
•
The voltage setpoints must be selected in a ascending manner (Vk+1>Vk).
•
The voltage value for last used set point should be set greater than the starting voltage. If this is not the
case, the starting voltage will be modified internally to the value of maximum voltage set value.
In general the factory default
LVRT-profile is preset based on the Type-I curve from Germany Grid Code 1)
(BDEW
2008) as shown in the following drawing:
LVRT-Default Profile (BDEW-TypI)
973 MCDLV4 DOK-HB-MCDLV4-2E
1

0.5

0 0.5 1 1.5 2 2.5 3
0
10
20
30
40
50
60
70
80
90
100
110
120
Default Voltage Profile (Germany Grid Code: BDEW-T ype I)
time [s]
V
ol
ta
ge
[
%
]
Vrecover>
Vstart<
V(t1)=0
t1 =0
V(t2)=0
t2 =0.15
V(t3)=0.70
t3 =0.15
V(t4)=0.70
t4 =0.70
V(t5)=0.90
t5 =1.50
V(t6)=0.90
t6 =3.00