Windmills and solar panels are only the visible part of the energy transition. The power grid itself, already one of the most complex systems ever designed by humankind, is undergoing its own transition to ensure a high enough reliability in a future with up to 100% distributed power generation.

System inertia

The green energy transition increases the risk of power failures, if not accompanied by a grid technology transition. Traditional large coal and gas power plants, with the high inertia of their heavy rotating generators, secure network stability. They ensure a minimal deviation from the desired 50 Hz output frequency even under a relatively large, temporary imbalance between mechanical power supplied and electrical power demanded. Smaller generators, such as windmills, are less stable and may need to be disconnected from the grid promptly after occurrence of a fault, as they may possibly affect system stability, which in turn might result in a cascading outage effect, ultimately leading to a blackout.

Split second decisions

Faults will always happen within a power grid and there is not one single best solution to deal with them. The challenges are to keep these faults localized to minimize the number of consumers affected, and to ensure a speedy recovery. Whereas the original 100-year-old power grid design allowed for hard-wired mechanical solutions following simple rules, the ever-increasing complexity of the current grid demands smart(er) solutions. Protection relays need to monitor the relevant parameters - such as voltage, frequency and current – at the proper sampling frequency. Algorithms will have only a short time interval (several milliseconds up to tens of milliseconds depending on the system nature) to autonomously make the correct decision based on these data. 

Leading institute

International connections increase network stability, making protection and governance of future power systems an international subject. The group of Intelligent Electrical Power Grids of the TU Delft decided to be the leading institute for this topic in Europe. They initiated the Power System Protection Centre in cooperation with the Dutch Transmission System Operator, Distribution System Operators, GE and Siemens to combine and promote the knowledge of power system protection among utilities companies, grid operators, manufacturers and academia. For their inaugural event they organized an international workshop with a top-notch speaker's lineup where the latest insights and solutions will be shared.

International workshop 21-2

The workshop ‘Protection of Future Power Systems - Challenges of the Future’ will be held on Wednesday 21 February 2018 at the Delft Science Center in Delft. More information can be found here.

Photo: Tennet