Files
EVOLV/wiki/findings/pump-switching-stability.md
znetsixe 6d19038784 docs: initialize project wiki from production hardening session
12 pages covering architecture, findings, and metrics from the
rotatingMachine + machineGroupControl hardening work:

- Overview: node inventory, what works/doesn't, current scale
- Architecture: 3D pump curves, group optimization algorithm
- Findings: BEP-Gravitation proof (0.1% of optimum), NCog behavior,
  curve non-convexity, pump switching stability
- Metrics: test counts, power comparison table, performance numbers
- Knowledge graph: structured YAML with all data points and provenance
- Session log: 2026-04-07 production hardening
- Tools: query.py, search.sh, lint.sh

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-07 16:36:08 +02:00

1.1 KiB

title, created, updated, status, tags, sources
title created updated status tags sources
Pump Switching Stability 2026-04-07 2026-04-07 proven
machineGroupControl
stability
switching
nodes/machineGroupControl/test/integration/ncog-distribution.integration.test.js

Pump Switching Stability

Concern

Frequent pump on/off cycling causes mechanical wear, water hammer, and process disturbance.

Test Method

Sweep demand from 5% to 95% in 2% steps, count combination changes. Repeat in reverse to check for hysteresis.

Results — Mixed Station (2x H05K + 1x C5)

Rising 5→95%: 1 switch at 27% (H05K-1+C5 → all 3) Falling 95→5%: 1 switch at 25% (all 3 → H05K-1+C5)

Same transition zone, no hysteresis.

Results — Equal Station (3x H05K)

Rising 5→95%: 2 switches

  • 19%: 1 pump → 2 pumps
  • 37%: 2 pumps → 3 pumps

Clean monotonic transitions, no flickering.

Why It's Stable

The marginal-cost refinement only adjusts flow distribution WITHIN a combination — it never changes which pumps are selected. Combination selection is driven by total power comparison, which changes smoothly with demand.