Woodward HighPROtec MCDLV4, Руководство пользователя, Страница: 607 / 1275

Protective Elements
Phasor Compensation
Please note: This section applies only if a step up transformer is part of the protected differential zone.
Please note: The reference side for the phasor compensation is assigned fixed to current measuring card W1.
The phase current phasor compensations are performed automatically and involve amplitude and phase
adjustments based on the system parameters, voltage ratings, tap position (assuming the tap changer is on the
winding 1 side), winding connections and groundings, and the secondary winding phase shift (n) relative to the
primary.
The compensated secondary current phasor on the transformer winding side W2 with winding side W1 as reference
winding can be expressed as follows:
⃗
I
W2
'
=
V
LL,W2
V
LL,W1
⋅
(
1
+
Tap Changer
)
⋅
CT
pri , W2
CT
pri , W1
⋅
⃗
I
W2
for magnitude compensation,
and
⃗
I
W2
' '
=
T
Phase Shift
(
n
)
⋅
⃗
I
W2
'
for angle compensation.
Note:
T
Phase Shift

n

is a complex factor due to transformer vector group setting.
607 MCDLV4 DOK-HB-MCDLV4-2E