ABB RELION REX640 Technical Manual page 912

Section 4
Protection functions
906
GUID-F6347695-8117-4B59-8FC0-AF3BFDC9076E V1 EN
Figure 497: Application scope of DSTPDIS
Typically these networks are operated in ring or meshed type configurations. The
switching state of these networks is changed frequently due to daily operation and load
flow considerations. The networks also include varying capacities of distributed
generation which makes it impossible to apply simple overcurrent-based schemes. In
these networks, DSTPDIS is used to provide a fast and selective protection for
overhead lines and power cables. It can also be applied for radial feeders to increase
the sensitivity of the protection, especially if the short circuit power of the source is
low or it changes due to network operation.
From the selectivity point of view, it is advantageous that in the protection chain all
functions in different positions operate according to the same measuring principle.
Therefore, DSTPDIS can also be applied for the backup protection of main
transformers and buses. This way, selectivity in the distance protection of the
outgoing lines is easier to achieve.
GUID-D57C40AC-C100-4143-B14F-8D5F81CCFCC4 V1 EN
Figure 498: Typical network configurations for DSTPDIS application
1MRS759142 C
REX640
Technical Manual