During this project Scottish and Southern Energy Power Distribution (SSEPD) propose to carry out the development of a 33/11kV power transformer using IEC 60076-14 limits to allow for using an ester-based fluid as an insulating medium at higher running temperatures.Completion of this project should provide us with a solution which can be used in situations where there are high safety and environmental concerns whilst providing a unit which can be reduced in size and cost.

The project will include the following stages;

• Business representatives liaising with the manufacturer to investigate a range of potential designs
• We will undertake a process of assessing and selecting the most suitable designs for a Continuous Maximum Rated (CMR) unit and a Continuous Emergency
• Rated (CER) unit based on potential operational and financial requirements
• The selected supplier will then be tasked with the manufacture of selected designs
• A complete unit will then be subject to enhanced transformer type testing processes before being deemed suitable
• Once testing is complete we will re-assess the potential impact on the business and re-visit initial cost benefit analysis
• Online dissolved gas analysis and fibre optic monitoring of winding temperatures will be installed for a period of 3 years
• The new design, if suitable, will be proposed to relevant departments for use in business as usual

The project management methodology followed in the project, included regular project reviews in order to assess progress and review the benefits case. Following a detailed project review, it has been found that the cost benefit analysis has changed in comparison to the original one. The changes constituted of reduced base cost (due to updates in internal company frameworks) and increased method cost (due to cost of additional materials required). As a result, the updated cost benefit analyses demonstrated that the investigated innovative technology will not offer financial benefits to the company and the customers. Considering the cost of stopping the project at an early stage, as compared to progressing with a project that will not deliver financial savings, it was decided that it is on the best interest of the company and the customers to stop the project prematurely and re-focus the efforts in other innovation projects with higher potential of delivering benefits.

Benefits

Phase 1 will seek to investigate the cost and operational implications of re-design and use of transformers built to IEC 60076-14 limits for use of ester-based fluids as an insulating medium.

Phase 2 will seek to investigate any detrimental affects on transformer performance over a 3 year monitoring period.

The success of the project will be to understand the implications of transformer re-design to allow for running at higher temperature limits.