I intend to do a few essays about electric power system stability. I aim to share some concepts about power generation and grids, and in particular how electrical stability is achieved.
Some types of generation provide grid stability, other types undermine it. Grid stability is an essential requirement for a power supply reliability and security. However there is insufficient understanding of what grid stability is and the risk that exists if stability is undermined to the point of collapse. Increasing grid instability will lead to power outages. The stakes are very high.
I will discuss various engineering concepts with readers, and I’ll try to do it in a way that is accessible. I’ll do my best to keep the discussion reasonably simple, sticking mainly to mechanical analogies rather than maths.
Here are some of the topics that I’ll be covering:
- There is no storage in the grid. Correcting an erroneous concept; what the grid is not.
- Energy balance and a definition of stability.
- Generator types; synchronous versus asynchronous machines: What goes on inside the machines?
- Frequency stability and energy balance. A description of the interaction between frequency and grid energy flow.
- Control of the prime mover, governors, how it is done and why it matters:
- A closer view of an under frequency event, showing the effects of inertia, load control and governor action.
I aim to do one of these a week.