ABB RELION REX640 Technical Manual page 455

1MRS759142 F
In the phasor diagrams representing the operation of DEFxPDEF, the polarity of
the polarizing quantity (Uo or U2) is reversed, that is, the polarizing quantity in the
phasor diagrams is either -Uo or -U2. Reversing is done by switching the polarity of
the residual current measuring channel (see the connection in the Protection relay's
physical connections section). Similarly the polarity of the calculated Io and I
switched.
For defining the operation sector, there are five modes available through the
Operation mode setting.
Table 530: Operation modes
Operation mode
Phase angle
IoSin
IoCos
Phase angle 80
Phase angle 88
The directional operation can be selected with the
alternatives are "Non-directional", "Forward" and "Reverse" operation. The operation
criterion is selected with the
to "True", non-directional operation is allowed when the directional information is
invalid, that is, when the magnitude of the polarizing quantity is less than the value
of the
Typically, the network rotating direction is counter-clockwise and defined as "ABC".
If the network rotating direction is reversed, meaning clockwise, that is, "ACB",
the equation for calculating the negative sequence voltage component need to be
changed. The network rotating direction is defined with a system parameter
rotation . The calculation of the component is affected but the angle difference
calculation remains the same. When the residual voltage is used as the polarizing
method, the network rotating direction change has no effect on the direction
calculation.
REX640
Technical Manual
Description
The operating sectors for forward and reverse are defined with
the settings
angle and Max reverse angle .
The operating sectors are defined as "forward" when |Io| x sin
(ANGLE) has a positive value and "reverse" when the value is neg-
ative. ANGLE is the angle difference between -Uo and Io.
As "IoSin" mode. Only cosine is used for calculating the operation
current.
The sector maximum values are frozen to 80 degrees respectively.
Only
The sector maximum values are frozen to 88 degrees. Otherwise
as "Phase angle 80" mode.
Polarizing quantity selection "Neg. seq. volt." is available only in the
"Phase angle" operation mode.
Min operate voltage setting.
The network rotating direction is set in the protection relay using the
parameter in the HMI menu: Configuration > System > Phase rotation.
The default parameter value is "ABC".
Enable voltage limit setting is set to "True", the magnitude of
If the
the polarizing quantity is checked even if
Allow Non Dir to "True".
directional" or
Min forward angle , Max forward angle , Min reverse
Min forward angle and Min reverse angle are settable.
Operation mode setting. By setting Allow Non Dir
Protection functions
Directional mode setting. The
Directional mode is set to "Non-
is also
2
Phase
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