National Grid
Engineering Critical UK Infrastructure
Discover TES Limited’s extensive portfolio of National Grid projects. From protection system upgrades and SPAR programmes to complex substation engineering, we deliver resilient high-voltage solutions across the UK transmission network.
Detail Projects
Case Studies
Thorpe Marsh 400kV MESH Corner Feeder, MESH Corner, and MESH DAR Protection Replacement
This 400kV substation was constructed with Air Insulated Switchgear and consisted of a four-switch mesh with 400/275kV SGT’s on mesh corners 1 & 3, a 400kV Shunt Reactor on Mesh Corner 2, and an additional 400kV Circuit Breaker on Mesh Corner 3.
The TES scope of work consisted of the replacement of the entire protection systems on 3 Mesh Corners and replacement of the MESH DAR protection using an overlay scheme that required complex interface engineering. This overlay methodology was implemented to help assist with stringent network constraints.
The detailed scope of work that was carried out by TES was as follows:
- Site specific scheme design utilising NICAP type registered standard bay solutions for the hub site and remote end substations
- Interfacing of new protection equipment into already installed equipment that is not being made redundant
- Red and Green multicore cable schedules and core sheets
- Removal of redundant line trap equipment
- Design of new protection front sheets for installation on site
- Protection settings calculations from given power system data
- Preparation of control system I/O information to facilitate multiple control system data base updates.
- Modification of existing protection and DAR schedules
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection panels
- Marking up of existing and production of new drawings
- Site scanning of hub site and remote end drawings
- Site filing of as-built drawings
- Project management, Temporary Works Coordination and SHEQ management
Case Studies
South Shields 275kV Substation Protection and Control Replacement
The scope of works was to install new protection and control for the following: Feeder Protection (Blyth-Tynemouth & West Boldon circuits), SGT HV/LV Protection, Mesh Corner Protection, S10 Circuit Breaker Protection, Mesh DAR and SCS at South Shields 275kV Substation. This also included the remote end works at Blyth, Tynemouth, West Boldon 275kV Substations.
The Scope of work that was carried out by TES was as follows:
- Project management, Temporary Works Coordination and SHEQ management
- Document Control and CAD
- Design Intent Document
- Bill of Materials
- Site specific scheme design utilising Siemens PLC type registered standard bay solution
- New Panel General Arrangements and Wiring Diagrams
- Interfacing of new equipment into already installed equipment. Including wiring diagrams, core sheets, cable schedules and block cable diagrams
- IO and GEMs
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection panels
- Construction Boxes
- Site filing of as built drawings
Case Studies
Elstree 400/132kV Clean Gas & SF₆ GIS Bay Extension
This project involved the extension of an existing 132kV GIS substation to accommodate two new customer circuits (UKPN Feeder 1 & 2) and an additional 400/132kV SGT bay to increase power capacity. New Protection & Control (P&C) engineering works were required across the existing 400kV GIS substation, the existing 132kV GIS substation, and the new 6‑bay 132kV clean‑gas extension building.
Transmission Engineering Services delivered the full protection engineering scope, including:
- Kit‑out of 2 skeleton bays in the existing 132kV GIS building for future feeders
- Conversion of a spare 400kV GIS bay into an SGT HV bay
- Engineering for 6 new bays at the clean‑gas extension:
- 2 × Feeder bays
- 1 × SGT LV bay
- 1 × Bus Coupler bay
- 2 × Bus Section bays
- Replacement and relocation of GIS earth switches
- 400/132kV new SGT and 275/132kV SGT replacement works
Protection & Control Engineering
- Site‑specific scheme design using NICAP type‑registered standard bay solutions
- Interfacing with existing electrical interlocking schemes and extending busbar protection to new bays
- Integration with the existing gas leakage monitoring system and development of a new system for extension bays
- Preparation of wiring diagrams and interfacing of new protection equipment with new plant
- Interfacing new protection equipment with existing non‑redundant systems
- Design and integration of PQM & HAM metering
LVAC and DC load calculations, cable sizing, and trip/close coil voltage‑drop calculations.
- Preparation of BOM and review of relay panel, control panel, and LCC General Arrangement drawings
- Preparation and modification of cable schedules (multicore, fibre optic, patch cords, Harting plugs), cable block diagrams, and core sheets
- Preparation of control system I/O information to support multiple control system database updates
- Mark‑up of existing drawings and production of new drawings
- Removal of redundant equipment
- Support for DID preparation, key line diagrams, design review meetings, and site queries
- Site scanning of hub‑site drawings
132kV Manually Switched Capacitor Protection Replacement
Transmission Engineering Services.
At this 132kV substation our scope of work included the replacement of existing Mechanically Switched Capacitor main and back-up and tertiary protections on MSC3 Banks A, B & C. The existing Reyrolle DAD, DCD314A, RH03, ABB SPAJ160C and Alstom KCGG142 protections were replaced with new in-situ NICAP protection solutions.
The detailed scope of work that was carried out by TES was as follows:
- Site specific scheme design utilising NICAP type registered standard bay solutions.
- Interfacing of new protection equipment into already installed equipment that is not being made redundant
- Red and Green multicore cable schedules and core sheets
- Design of new protection front sheets for installation on site
- Protection settings calculations from given power system data
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection tiers
- Marking up of existing and production of new drawings
- Site scanning of existing site drawings
- Site filing of as-built drawings
- Project management, CDM, Temporary Works Coordination and SHEQ management
- Preparation and submission of the Commissioning Switching Programme
Technical Compliance & Type Registration
Navigating National Grid’s rigorous technical standards requires precision and experience. TES Limited supports manufacturers and the Grid by managing the Type Registration process, ensuring new technologies are approved for use on the network.
- Static Synchronous Series Compensation: Equipment protection type registration for various sites.
- SGT LV Connections: Circuit Breaker Control and BUP Protection Type Registration.