ABB RELION Series Technical Manual page 626

Section 9
Control functions
620
• The measured line and bus voltages are higher than the set values of Live bus
value and Live line value (ENERG_STATE equals to "Both Live").
• The measured bus and line frequency are both within the range of 95 to 105
percent of the value of f
• The measured voltages for the line and bus are less than the set value of Max
energizing V.
In case Syncro check mode is set to "Syncronous", the additional conditions must be
fulfilled.
• In the synchronous mode, the closing is attempted so that the phase difference at
closing is close to zero.
• The synchronous mode is only possible when the frequency slip is below 0.1
percent of the value of f
• The voltage difference must not exceed the 1 percent of the value of U
In case Syncro check mode is set to "Asyncronous", the additional conditions must be
fulfilled.
• The measured difference of the voltages is less than the set value of Difference
voltage.
• The measured difference of the phase angles is less than the set value of
Difference angle.
• The measured difference in frequency is less than the set value of Frequency
difference.
• The estimated breaker closing angle is decided to be less than the set value of
Difference angle.
Difference angle
U_Bus
GUID-191F6C44-7A67-4277-8AD1-9711B535F1E1 V2 EN
Figure 316: 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
.
n
.
n
= -
U_Bus U_Line
Difference voltage
U_Line
Live line or bus value
Dead line or bus value
Frequency deviation
1MRS758755 A
.
n
Difference frequency
f f f
= abs( - )
U_Bus U_Line
f
f
U_Line
U_Bus
Frequency[Hz]
Rated frequency
REC615 and RER615
Technical Manual