The science · model, assumptions & equations
1 · Wind turbine power
ρ is air density (kg/m³), A is swept area (m²), Cp is a dimensionless power coefficient, v is wind speed (m/s), and N is the number of turbines. The result is converted from watts to megawatts.
2 · Grid frequency response
Frequency f is in hertz; power is in megawatts; H is an approximate inertia constant in seconds; D is a damping coefficient in s⁻¹. A single-bus first-order model is used to make the response understandable.
3 · Battery energy
Positive battery power means discharge. Negative power means charging. The controller applies a simple frequency-droop rule and respects minimum and maximum state-of-charge limits.
Solver & assumptions
State updates use a fixed 1/120-second semi-implicit Euler step with an accumulator. The dashed analytic curve assumes today's net power imbalance stays constant; it is an approximate short-horizon reference, not a second simulation. Wind density is fixed, turbines are aggregated, and the battery uses an idealised energy balance. Weather and demand changes are scripted educational events.
What this model leaves out
- No AC power-flow, voltage, reactive power or transmission-line constraints.
- No blade pitch, wake interaction, generator transients or cell-level battery effects.
- Demand response is a simplified temporary load reduction.
Use: educational exploration only; not for operating a real electricity network.