difference frequency for sychronization
difference frequency for sychronization
(OP)
IEEE C50.12 – 2005 define Synchronizing limits:
4.2.2 Synchronizing
Generators shall be designed to be fit for service without inspection or repair after synchronizing that is
within the limits listed in Table 2.
—Synchronizing limits
Breaker closing angle ±10º
Generator side voltage relative to system 0% to +5%
Frequency difference ±0.067 Hz.
Additional information on synchronizing practices can be found in IEEE Std C37.102™-1995 [B8].
We have seen 0.1 or 0.2 Hz as frequency difference. Have you seen another limit?
4.2.2 Synchronizing
Generators shall be designed to be fit for service without inspection or repair after synchronizing that is
within the limits listed in Table 2.
—Synchronizing limits
Breaker closing angle ±10º
Generator side voltage relative to system 0% to +5%
Frequency difference ±0.067 Hz.
Additional information on synchronizing practices can be found in IEEE Std C37.102™-1995 [B8].
We have seen 0.1 or 0.2 Hz as frequency difference. Have you seen another limit?






RE: difference frequency for sychronization
xnuke
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RE: difference frequency for sychronization
The 0.067 limit is endorsed by the standard C37.102-1995-item 5.
Interestingly, generator could be fit for service without inspection or repair after synchronizing.
RE: difference frequency for sychronization
measuring 60Hz wee have an error of 0.18Hz.
How can I measure 0.067Hz ?
RE: difference frequency for sychronization
Regards
Marmite
RE: difference frequency for sychronization
We measure Frequency by PT, that means we convert voltage TPs value in Hz. (Hz= k * Vpt). All error in PT will be transfered to measuring.
RE: difference frequency for sychronization
for a o.o67 hertz error, that would be 15 second "sweep" on the synch scope.
the 0.2 hertz error would be a 5 second clock. While I'm not an operator, that seems pretty fast to be closing in
RE: difference frequency for sychronization
RE: difference frequency for sychronization
- I know of no electric utility that adopts 0.067 Hz limit.
-The national electric system operations in Brazil (ONS) suggests values of 0.1 or 0.2Hz.
Do you know any colleague or concessionary questioning the viability of this limit (0.067)?
RE: difference frequency for sychronization
.."IEEE Standard 67.................. However , in practice, wider limits are often applied because the prime mover control is not fine enough to reliably achieve a 0.067 slip.