Lab 5 — Stability and CCT

Goals¶

Create reference labels and CCT brackets on classical SMIB (Lab 1 tooling), then evaluate a learned surrogate or forward PINN near the boundary. Report signed and absolute CCT errors, false-safe decisions, and one case where trajectory ranking and CCT ranking disagree.

Prerequisites¶

• Lab 1

• Prefer also Lab 2

• Chapters: CCT, surrogate stability, optional direct methods

Reference CCT (no ML yet)¶

Using simulate_smib / angle_stable:

1. Fix prefault state and fault inception

2. Sweep or bisect clearing time until the operational label flips

3. Record bracket width and tolerance

4. Optional: if the case matches equal-area assumptions, compare search CCT to the classical estimate (direct methods)

Learned CCT (after Lab 2)¶

Replace the inner trajectory call with a surrogate; keep the same stability rule. Compare $\hat{t}_{\mathrm{CCT}}$ to the reference CCT.

Deliverables¶

• Reference CCT table for ≥3 operating / fault settings

• Signed CCT errors for the learned method

• False-safe count on a boundary-focused set

• One disagreement case write-up

Materials (launch paths)¶

• Assessed SMIB path: use Lab 1 tooling locally until the dedicated SMIB CCT notebook is added; then Binder/Colab badges will match Labs 1 and 3

• ANDES network extension is local only (not on Binder / Colab)

Optional network extension (after this lab)¶

Assessed Lab 5 stays on classical SMIB. When SMIB CCT works, the preferred network follow-on is Kundur via ANDES (not a sixth assessed lab):

• Notebook: lab05_network_cct_andes.ipynb — one-bus CCT sweep + signed error / false-safe metrics (local / envs/course_andes.yml only)

• Helper: sciml_ps.andes_cct (requires envs/course_andes.yml, andes==2.0.0)

• Bridge page: ANDES as network reference

• Official full map (link only): Critical Clearing Time Mapping

Status¶

Narrative and protocol ready; full SMIB surrogate CCT notebook follows Lab 2. Network extension notebook + ANDES pin (2.0.0) are in place.