Simulate local disturbances
Click on a node on the map to perturb its position and speed by these values.
What do I see?
This is a simulation of the Scandinavian high-voltage power transmission network. The links are transmission lines, they change their width proportional to their usage. The nodes are sites of power producers or consumers.
The nodes produce or consume AC power and behave as so-called oscillators.
Think of them as fast-running clocks which exchange their current time via the links. In stable operation of the power grid, all clocks are required to run at the same global speed, i.e. no clock is overturning another one. Speed deviations are visualised in the changing size of the nodes.
When the clock speed is the same at all nodes, the time differences between them are constant. Each of the nodes is its own time zone, with some being in advance and some being behind of the others. After each clock cycle, the positions are identified. Nodes that are behind draw power from advanced nodes. This determines the direction of power transmission.
Synchronization
The normal operation at the global clock speed with constant time differences is called synchronisation. In Europe, the nodes are synchronised at a global speed of 50Hz, i.e. clock cycles per minute. The larger the “time difference” between two nodes, the more power is being transmitted between them.
At a base speed of 50hz the clocks appear to stand still. By reducing the base speed, you reduce the slow-motion effect until you observe the real-time simulation.
Each clock is subject to a certain amount of friction when it deviates from the global speed. By increasing the friction multiplier, the power grid becomes more stable.
Experiments with disturbances
You can manually perturb the clock position and speed of any node by clicking on it. The size of the perturbation can be selected with the sliders on the left.
Alternatively, you can observe predefined perturbations at special nodes
node in appendices Here, it should be comparably easy to desynchronise a small group of nodes from the rest. A disturbance in an appendix is typically confined there.
hub (a node with many neighbours) The more neighbours a node has, the more likely are large speed deviations after a disturbance.
detour node (a node parallel to a direct connection) Here, it should be difficult to destabilise the power grid.
dense sprout (an end node connected to node with many neighbours) Perturbing a dense sprout can cause an interesting effect: A single node running at its own speed while the remaining network is in synchronisation. It is an effect predominantly affecting dense sprouts.