ABB is partnering with UK Power Networks in the NIC-funded PowerFul-CB (Power Electronic Fault Limiting Circuit Breaker) project that is intended as a forerunner for the connection of more distributed generation (including combined heat and power schemes) on London’s electrical distribution networks. The project will see deployment of the world’s first fault current limiting solution based on compact power electronics. It will be able to will respond to a fault current within 0.35 milliseconds with the added benefit that it can be reset as soon as the fault current is cleared.
For decarbonisation of heating, for which a key element is the growth of district heating and distributed generation, to be successful there will be an increase in the number of DG connections to the network. Constraints such as ‘fault level headroom’ may then become a factor for connecting new DG in urban areas. In one scenario, London will see a greater than six-fold increase in connecting CHP by 2031, which would drive much higher DG integration costs.
Traditional solutions such as network reinforcement will make new DG financially unattractive, and in London in particular with its strict limits on available space. To get around this objection the PowerFul-CB project has been created to test an innovative fault current limiting technology on 11 kV distribution networks, and evaluate its effectiveness for connecting more DG customers.  If successful, it is estimated that by 2050 this new technology could be saving UK customers millions of pounds.
In the first two years of the project, which starts in January 2017, ABB will use its existing 2000A power electronic fault current limiter technology to build a full prototype for a trial installation at a primary substation. The aim is to demonstrate its suitability as a smart, cost-effective long term solution for multiple DG connections.
Suleman Alli, director of Safety, Strategy and Support Services at UK Power Networks, commented: “We are setting out to meet the demand from developers and businesses who want to generate environmentally-friendly, cost-efficient energy. By reducing the cost of connecting smaller-scale energy generation to the network, we will enable more CHP devices to connect to the network and provide low-carbon energy for Londoners.”
Peter Jones, ABB Technology Strategy manager, commented: “Fault currents can be a major barrier to the connection of DG. But while a number of smart solutions are already available they do not meet London’s unique physical and operational constraints in terms of lack of space for new substation equipment and the need to ensure security of supply. The PowerFul-CB project will enable us to demonstrate an innovative approach that offers a compact option to achieve a quicker and more cost-effective connection to fault-level-constrained networks.”