ABB RELION REF615R, Technical Manual

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Dead line or bus value
Live line or bus value
Difference angle
V_Bus
V_Line
Difference voltage
f
V_Bus
f
V_Line
Frequency[Hz]
f
=
f
V_Bus
-
f
V_Line
Rated frequency
Frequency deviation
=
V_Bus
-
V_Line
Difference frequency
GUID-72527DBF-2FC1-4E3B-BE9D-E5978DB3BDA4 V2 EN
Figure 260: Conditions to be fulfilled when detecting synchronism between systems
When the frequency, phase angle and voltage conditions are fulfilled, the duration of the
synchronism conditions is checked so as to ensure that they are still met when the
condition is determined on the basis of the measured frequency and phase difference.
Depending on the circuit breaker and the closing system, the delay from the moment the
closing signal is given until the circuit breaker finally closes is about 50...250 ms. The
selected
Closing time of CB informs the function how long the conditions have to persist.
The Synchro check function compensates for the measured slip frequency and the circuit
breaker closing delay. The phase angle advance is calculated continuously with the
formula.
Closing angle V V f f T T
Bus Line Bus line CB PL
= ∠ − ∠
( )
° + −
( )
× +
( )
× °
( ) 360
GUID-1B5A128E-E351-4847-93C8-6664FF822FE9 V1 EN
(Equation 30)
∠V
Bus
Measured bus voltage phase angle
∠V
Line
Measured line voltage phase angle
f
Bus
Measured bus frequency
f
line
Measured line frequency
T
CB
Total circuit breaker closing delay, including the delay of the protection relay output contacts defined
with the
Closing time of CB setting parameter value
The closing angle is the estimated angle difference after the breaker closing delay.
The Minimum Syn time setting time can be set, if required, to demand the minimum time
within which conditions must be simultaneously fulfilled before the SYNC_OK output is
activated.
The measured voltage, frequency and phase angle difference values between the two sides
of the circuit breaker are available as monitored data values V_DIFF_MEAS,
Section 9
1MRS240050-IB C
Control functions
500 REF615R
Technical Manual