NG TS 3.24.85 PDF

PURPOSE AND SCOPE

This specification defines the generic technical requirements for Automation Schemes for the management of power system constraints

Automation Schemes operate primary equipment to automatically reconfigure the primary network to prevent abnormal system conditions occurring which could lead to thermal overloading, system instability, the potential to temporarily overstress switchgear, voltage transgression or loss of supply 

To accomplish this, Automation Schemes are configured to perform pre-determined switching sequences that will result in the sequenced opening and/or closing of combinations of circuit breakers and occasionally disconnectors. This functionality is used to overcome power system constraints that limit the ability to:-

• Utilise the circuit capacity available to supply local distribution networks.

• Provide transmission export capacity to local Generation following a fault.

Auto Close schemes are normally used to automatically undertake simple network re-configuration sequences but may be specified to provide more complex operations i.e. the operation of disconnectors and circuit breakers to re-configure substation busbars or circuit connectivity.

To facilitate use of this specification, Appendix D shows an informative example of a comprehensive generic Automation Scheme for an Auto Close application. This example illustrates a system designed to perform complex sequences, operating disconnectors and circuit breakers while obtaining information from a number of substation locations. Simple systems may be reduced in complexity to avoid providing unwanted and unnecessary equipment. Other scheme specific technical requirements will be defined by separate specifications which should be read in conjunction with this specification. These separate specifications are detailed in Appendix A

The purpose of this specification is to define the complete set of functionality required by an Automation Scheme for Auto Close sequences. An Automation Scheme Functional Requirements Specification (ASFRS) shall define which features are required

Specific application technical requirements shall be defined separately within a unique functional specification for each Automation Scheme. Each scheme specific functional specification should be read in conjunction with this Technical Specification. Unless specified otherwise in the scheme specific functional specification, all requirements of this Technical Specification shall apply.

This specification makes reference to or should be read in conjunction with the documents listed in the references section of this specification