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Use Case Main Bend Quench
ML - Notes following presentation by Reiner Denz.
Sequence (see diagram below)
- One magnet quench - quench detector sees > 100 mV
- 10.5 ms later triggers the quench
- Current loop opens
- Quench loop controller dumps PM buffers & signal Energy extraction, PIC
and Main bus bar
- PIC throws a fast power abort
- All 600A circuits could produce 2 PM buffers (EE & QPS)
- During current decay - other main circuits could quench
- 4-5 other MB around 20 s after first quench, will immediately trigger
other systems (EE, bus bars...)
- DS could see signals - interpreted as quench
- Need to track current for 5 minutes after quench to zero A. 2 Hz logging
would do it - have to get this data into PM system, or PC have to cover it in
their PM buffers.
- Timestamps to 1 ms precision
So stress on PM system
- 50 to 100 PM events with the QPS and EE systems. Burst of 45, say followed
by a dribble.
- Up to 6 gateways involved
- Acquired data visible at logging sample rate while filling PM buffers.
Important for 13 kA systems.
- 61 kbytes binaries coming up at 480 bytes/s per controller
- Lets say 50 buffers - 3 megabytes (which @ 48 kbytes/s will take 3
minutes)
- 9 different types of buffer - tag with agent (DDAQm...
/timestamp)
PIC
All digital, 36 PICs in ring. Each change of input/output recorded as record
(UTC/who/etc.) Circular oversized buffer. Push to PM system and/or logging.
Similarly for BIC
