Settings Of The Reverse Power Protection - Siemens Siprotec 7UM62 Manual

Pickup Seal-In Time
Time Delays

2.15.2.1 Settings of the Reverse Power Protection

Addr. Setting Title
3101 REVERSE POWER OFF
3102 P> REVERSE
3103 T-SV-OPEN
3104 T-SV-CLOSED
3105A T-HOLD
7UM62 Manual
C53000-G1176-C149-3
= √3 ⋅ U ⋅ I
S
Nsec Nsec Nsec
to secondary quantities using the following formula:
P
Setting -------------- -
=
S
Nsec
with P Secondary active power according to setting value
sec
Secondary rated power = √3 ⋅ U
S
Nsec
P Active power of machine according to setting value
mach
S Rated apparent power of machine
N mach
U Rated voltage of machine
N mach
Rated current of the machine
I
N mach
U Primary rated voltage of voltage transformers
N prim
I Primary rated current of current transformers
N prim
The 3105A T-HOLD pickup seal-in time serves to extend pulsed pickups to the
parameterized minimum duration.
If reverse power without emergency tripping is used, a corresponding time delay must
be considered to bridge short reverse power states after synchronization or power
swings subsequent to system faults (e.g. 3-pole short circuit). Usually, a time delay
3103 T-SV-OPEN = approx. 10 s is set.
Under emergency tripping conditions, the reverse power protection performs a short-
time delayed trip subsequent to the emergency tripping via an oil-pressure switch or a
position switch at the emergency trip valve. Before tripping, it must be ensured that the
reverse power is only caused by the missing drive power at the turbine side. A time
delay is necessary to bridge the active power swing in case of sudden valve closing,
until a stationary active-power value is set. A 3104 T-SV-CLOSED time delay of about
1 to 3 s is sufficient for this purpose, whereas a time delay of about 0.5 s is
recommended for gas turbine sets. The set times are additional time delays not
including the operating times (measuring time, drop-out time) of the protective
function.
Setting Options
ON
Block relay for trip com-
mands
-30.00..-0.50 %
0.00..60.00 sec; ∞
0.00..60.00 sec; ∞
0.00..60.00 sec; ∞
. If the primary motoring energy is known, it must be converted
P U
sec mach N mach
⋅
------------------- - -------------------- -
=
S U
N mach N prim
Default Setting
OFF
-1.93 %
10.00 sec
1.00 sec
0.00 sec
Reverse Power Protection (ANSI 32R)
I
N mach
⋅
----------------- -
I
N prim
⋅ I
Nsec Nsec
Comments
Reverse Power Protection
P> Reverse Pickup
Time Delay Long (without Stop
Valve)
Time Delay Short (with Stop
Valve)
Pickup Holding Time
117