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
---
title: Pump Switching Stability
created: 2026-04-07
updated: 2026-04-07
status: proven
tags: [machineGroupControl, stability, switching]
sources: [nodes/machineGroupControl/test/integration/ncog-distribution.integration.test.js]
---
wiki: crisp overhaul — no decoration emoji, all 9 master pages refactored
Source-tree mirror of EVOLV.wiki.git refactor (27a42ee on wiki.git):
- 7 master pages rewritten with clean design (Home, Architecture,
Topology-Patterns, Topic-Conventions, Telemetry, Getting-Started,
Glossary). Tables and Mermaid for visuals, gitea alert callouts for
warnings, shields badges for metadata only. No emoji as decoration.
- Archive.md becomes a removal-changelog pointing readers to git
history and to the successor pages.
- _Sidebar.md updated to navigate the new flat-name layout.
- Concept / finding / manual pages: uniform mini-header (badges +
"reference page" callout) added without rewriting domain content.
- Every internal link now uses the flat naming that resolves on the
live gitea wiki (Concept-ASM-Models, Finding-BEP-..., etc.).
On wiki.git: 29 Archive-* pages hard-deleted (the git history
preserves them; Archive.md documents the removal).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-11 22:24:51 +02:00
 
> [!NOTE]
> Reference page. Maintained for context; not regenerated by code. See [Home](Home) for current top-level navigation.
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
# 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.
