NG TS 3.24.25 PDF

PURPOSE AND SCOPE

This document defines the requirements for configuring National Grid substations to the IEC61850 standard. By following this specification interoperability between devices from different suppliers will be possible and to some extent interchangeability of devices can be achieved.

The IEC61850 standard is used for communication between the Substation Control System (SCS) and Intelligent Electronic devices (IEDs) over the Substation Bus, herein referred as the Station Bus, and for communication between IEDs and Merging Units (MUs) over the so called Process Bus.

The standard also uses a Substation Configuration Language (SCL) that standardises the information modelling and communication configuration, which is crucial for interoperability.

The Architecture for Substation Secondary Systems (AS3) mandated in this specification is based on the process bus topology and communication functions defined in IEC61850-7-1, as well as the “Golden Rules” mentioned in Section 1.

The scope of this specification will allow for process bus redundancy to ensure improved reliability for the standard bay solutions developed for the UK National Grid. This leads to a topology and communication function requirements as shown in the example in Figure 1. The numbers refer to standard communication functions and data flow as shown below:

1. Sampled value exchange for CTs and VTs

2. Fast exchange of I/O data for protection and control ,

3. Control and trip signals

4. Engineering

5. Monitoring and supervision

6. Control-Centre communication (not part of the scope of this specification