DOC. MIE91093 Rev. 1.34
Page 112 of 145
1.15
T
RANSFORMER DIFFERENTIAL RELAY TESTING WITH
D1000
OR
TD1000
PLUS
1.15.1 Introduction
This test is performed taking advantage of the option D1000
or of the model TD1000 PLUS, that allow performing the
following tests of differential relays:
Characteristic curve test;
Harmonic restraint.
Before proceeding with the test description, we give some
basic hints on differential transformer protections.
1.15.2 The transformer
There are many ways for connecting the transformer
primary and secondary windings; they are classified as
vectorial group.
I
A
is the primary current phase 1
I
a
is the secondary current phase 1
Depending on the connections of winding 1 and 2 and the
polarity, the vectorial groups are as follows:
Yy0 – Yy6
Dy1 – Dy5 – Dy7 – Dy11
Yd1 – Yd5 – Yd7 – Yd11
Dd0 – Dd2 – Dd4 – Dd6 – Dd8 – Dd10
CONNECTION DAB
CONNECTION DAC
