Siemens SIPROTEC 7UM62, Manual

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Reverse Power Protection (ANSI 32R)
117
7UM62 Manual
C53000-G1176-C149-3
S
Nsec
=
√
3
⋅
U
Nsec
⋅
I
Nsec
. If the primary motoring energy is known, it must be converted
to secondary quantities using the following formula:
with P
sec
Secondary active power according to setting value
S
Nsec
Secondary rated power =
√3 ⋅
U
Nsec
⋅
I
Nsec
P
mach
Active power of machine according to setting value
S
N mach
Rated apparent power of machine
U
N mach
Rated voltage of machine
I
N mach
Rated current of the machine
U
N prim
Primary rated voltage of voltage transformers
I
N prim
Primary rated current of current transformers
Pickup Seal-In Time The
3105A T-HOLD
pickup seal-in time serves to extend pulsed pickups to the
parameterized minimum duration.
Time Delays 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.
2.15.2.1 Settings of the Reverse Power Protection
Setting
P
sec
S
Nsec
---------------
P
mach
S
N mach
--------------------
U
N mach
U
N prim
---------------------
I
N mach
I
N prim
------------------
⋅ ⋅
= =
Addr. Setting Title Setting Options Default Setting Comments
3101 REVERSE POWER OFF
ON
Block relay for trip com-
mands OFF Reverse Power Protection
3102 P> REVERSE -30.00..-0.50 % -1.93 % P> Reverse Pickup
3103 T-SV-OPEN 0.00..60.00 sec;
∞
10.00 sec Time Delay Long (without Stop
Valve)
3104 T-SV-CLOSED 0.00..60.00 sec;
∞
1.00 sec Time Delay Short (with Stop
Valve)
3105A T-HOLD 0.00..60.00 sec;
∞
0.00 sec Pickup Holding Time