ABB Remote I/O RIO600 Installation And Commissioning Manual page 163

1MRS757488 H
RIO600
Installation and Commissioning Manual
First condition for detection of fault passage is based on evaluation simultaneously the
phase angles of three ratios of changes in phase current phasors (fundamental
frequency) due to the earth fault:
 
1
∆
I
FPI_AtoB =
  A  
angle
∆ 1
I
 
B
GUID-D515DEC4-C291-4B9B-8F72-923551F553A5 V1 EN

∆ 1
I
FPI_BtoC =
  B
angle
∆ 1
I

C
GUID-5D1B6E80-64DB-4DF1-BA3C-C031DA278C57 V1 EN

∆ 1
I
FPI_CtoA =
C
 
angle
∆ 1
I

A
GUID-B3F99130-AEB9-4E9C-A0CF-3BFDE75A3CA2 V1 EN
where
ΔI = I (t ) - I (t
A A FLT A PRE_FLT
ΔI = I (t ) – I (t
B B FLT B PRE_FLT
ΔI = I (t ) – I (t
C C FLT C PRE_FLT
Actual implementation uses CPS calculation. Accumulation of phasors is started
when the presence of earth fault in the network is confirmed and accumulation of
phasors is reset when fault condition is over, and after Reset Delay Time has elapsed.
The indication of fault passage is declared when:
• the maximum phase angle is above setting Angle Sector AND
• the minimum phase angle is below setting -Angle Sector
Additionally, the absolute values of maximum and minimum phase angles of
Equations 23 - 25 in the faulted feeder should be equal. Their difference, that is, the
phase angle offset (= maximum – minimum phase angle) must not exceed setting
threshold Angle Offset Sector.

 


 

) = change of phase A current phasor due to earth fault
) = change of phase B current phasor due to earth fault
) = change of phase C current phasor due to earth fault
Section 6
Commissioning
(Equation 23)
(Equation 24)
(Equation 25)
155