ABB Relion 670 Series Technical Reference Manual page 287

Line differential protection ansi

Hide thumbs Also See for Relion 670 Series:

Table of Contents

1MRK505222-UUS C

Technical reference manual

ANSI06000417 V1 EN

Principle for zero-sequence voltage polarized additional directional

Negative-sequence voltage polarization is utilizing the phase relation between the

negative-sequence voltage and the negative-sequence current at the location of the

Zero-sequence current polarization is utilizing the phase relation between the zero-

sequence current at the location of the protection and some reference zero-sequence

current, for example, the current in the neutral of a power transformer.

The principle of zero-sequence voltage polarization with zero-sequence current

compensation is described in figure 144. The same also applies for the negative-

sequence function.

ANSI06000418 V1 EN

Principle for zero sequence compensation

Note that the sequence based additional directional element cannot give per phase

information about direction to fault. This is why it is an AND-function with the normal

en06000417_ansi.vsd

Impedance protection

Characteristic

en06000418_ansi.vsd

Relion red670