Physics-based Models for Cascading Failures of Power Grids Flashcards
What are the main steps of a physics-based model for
cascading failure analyses of a power system?
1.Initial system state: generation = demand
2. Run Montecarlo to generate Contingencies
3. Island Identification
4. Evaluate Frequency Deviaition
-> re-establish load balance
5,. Evaluate Voltage
5.. Check if Branch Flow exceeds limitation
Why do we introduce contingencies (failures)?
We want to test the system failure behaviour under unforseen circumstances to identify the limits and vulnerabilites of the system
How do we generate the contingencies?
We use Mote Carlo Simulations.
What does the frequency control do?
Frequency control ensures that the generator units do not run at underspeed and overheat or overspeed and self-destruct from rotational forces
What does the under-frequency load shedding do?
By shedding load, the load balence can be re-established. Here Loads with low priority are dropped first, such as pumped storage
What does the under-voltage load shedding?
Undervolt-Schedding drops loads so that the voltage between generation and demand can recover
What type of results a cascading failure model provides?
It provides continguncies that lead to cascading failures. This can be used to improve control and adapt the grid accordingly to improve reliability.
It also simultes the expected power losses and shows island formation.
What are the main difference between topological and
physics-based models for cascading failure analyses?
Mention some advantages and disadvantages?
Topological models provide quantitative analysis, that is easy to implement with little data. Such as how much additional load can my system handle or how robust is it against cascading failures on an abstract level.
Physics based model allow for in-depth analysis for but also need much more data and are more complicated to conduct
