Dielectric solutions for solid insulating components in eco-efficient medium-voltage switchgear

ABB will, in collaboration with SINTEF Energy Research and NTNU, use direct numerical simulations and ultrafast imaging experiments to optimize the design of solid insulating parts in new SF₆-free 12/24 kV F-panel switchgear modules. The F-panel concept design will be prototyped and tested in the project. This project addresses thematic priority area 2 - renewable energy, area 3 - the energy system and markets and area 4 - energy consumption and conversion in the ENERGIX work programme by pushing the development of the SF₆-free technology for MV switchgears forward.

Compact gas insulated switchgears contain live, high voltage conductors and switches. Electrical insulation between these parts is typically provided by sulphur hexafluoride (SF₆) gas. SF₆ is an excellent electrical insulator, but unfortunately a strong greenhouse gas. Replacing SF₆ over the entire medium-voltage portfolio with eco-friendly gases requires elaborate dielectric design.

This project aims to improve the dielectric performance by implementing optimal surface profiles on internal insulating parts in MV switchgear. This will be addressed through experimental and numerical modelling in a collaboration between ABB Electrification, SINTEF Energy and NTNU.

Background:

ABB Electrification Norway AS in Skien manufactures 12, 24 and 36 kV gas insulated compact switchgears for the world market. These switchgears have traditionally used sulphur hexafluoride (SF₆) as the main electrical insulation, which is a highly potent greenhouse gas (23 000 times stronger than CO₂). Restrictions on the use of SF₆ gas are in a planning phase by the EU commission and currently undergoing a public consultation process.

Through earlier collaborative research, ABB has brought an SF₆-free switchgear portfolio to the market, replacing SF₆ with air (for 12 kV) and mixtures of air and C5-fluoroketone (for 24 kV) under the trade name AirPlus™.

In order to meet future market demands and to comply with upcoming EU regulations, ABB must extend its SF₆-free portfolio with 12 & 24 kV switchgear modules with fuses (referred to as F-panels) and also future SF₆-free 12/24/36 kV models with enhanced ratings and lower costs. The less efficient insulation properties of air and AirPlus™ compared to SF₆ creates a major challenge for the development of the new SF₆-free switchgear modules.

Project lead: ABB Electrification Norway AS v/Elham Attar