Blackhillock 275kV AC Power Flow Control

About the Project

The East Coast 400kV Upgrade, comprises of works at Blackhillock, Kintore, Fetteresso and Alyth substations including the re-insulation of overhead lines (OHLs) between Kintore, Fetteresso, Alyth and Kincardine (in SPTs area). Corresponding works will be undertaken in a coordinated manner by Scottish Power Transmission in their licence area.


The system requires the installation of two Phase Shifting Transformers, on the 275 kV double-circuit overhead lines (OHLs) between Knocknagael, Berryburn, Dallas and Blackhillock (CA1-AH1/CU2-UH2) and are to be situated at Blackhillock 275 kV substation. It has been identified that the Phase Shifting Transformers must be installed on the network pre-2030 in preparation for the ASTI construction period, or there will be a significant reduction in B4 transfer capability.


The scope of works for this project will involve the supply and installation of two Phase Shifting Transformers 275/275kV 785/935 MVA at Blackhillock 275 kV Substation with the approximate grid reference of NJ 43311 48632, 343311 Easting, 848632 Northing. Modifications to the existing layouts shall take cognisance of the requirement for installation of bypass circuits on each feeder. The design shall focus on the PSTs being installed, and modifications to the circuits with the allowance of possible relocation of the PSTs in the future. The bypass arrangements shall require 3 x AIS disconnectors and AIS connections for the AH1 and UH2 circuits.

Community Engagement

Throughout the life of our projects, we aim to work positively with local communities and keep people informed about what we are doing. This is particularly important when we are developing a proposal and we want to understand what local people think about our plans.

We endeavour to take the time to discuss proposals with local community councils, encourage engagement from the wider community and listen to the feedback we receive.

We will do our best to answer any questions and address issues or concerns that are raised with us.

When our project progresses into construction, we will continue working closely with the local community to ensure that our work has as little impact on the lives of those living and working in the area and as many long term positive effects as possible.

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