D - Michigan State University

FRIB MPS Fast Protection System
Yihua Wu
Controls Engineer
This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
Michigan State University designs and establishes FRIB as a DOE Office of Science National User Facility in support of the mission of the Office of Nuclear Physics.
Outline
 Requirement and architecture
 FPS response time analysis
Y. Wu, March 2014 MPS Workshop - 05D, Slide 2
MPS/GTS Overview
 MPS — Machine Protection System
 RPS — Run Permit System
 FPS — Fast Protection System
 GTS — Global Timing System
Y. Wu, March 2014 MPS Workshop - 05D, Slide 3
FPS Response Time Requirement
 MPS response time requirement
• 35 μs for Linac Segment (LS) 2
• 45 μs for Linac Segments 1 and 3, Folding Segments 1 and 2, and the Beam Delivery System
(BDS)
• >45 μs for other zones
 MPS response time sharing
15 μs
FPS Response Time
10 μs
Sensing and indicating
an error condition
From input OK/NOK to output
signal to mitigation device
Shutting down machine
by mitigation device
 FPS response time requirement
• 10 μs for Linac Segment (LS) 2
• 20 μs for Linac Segments 1 and 3, Folding Segments 1 and
2, and the Beam Delivery System (BDS)
• >20 μs for other zones
 Design objective
<10 μs for All
Y. Wu, March 2014 MPS Workshop - 05D, Slide 4
FPS Architecture
To mitigation Device
RF 80.5MHz input
UDP
GTS
GTS
UDP
FPS Master
Big-head
signal wires
Run Permit
System
UDP
Management
Computer
CAT5 cable
Fiber for FPS
Fiber for GTS
Hardwire
Parallel process
Daisy Chain
FPS Slave
Node
Cryomodule
#1
...
Daisy Chain
FPS Slave
Node
...
FPS Slave
Node
Cryomodule
Cryomodule
#8
#49
...
FPS Slave
Node
Cryomodule
#56
Y. Wu, March 2014 MPS Workshop - 05D, Slide 5
FPS Delay Time Definition
FPS MASTER
FPS SLAVE #1
FPS SLAVE #2
FPS SLAVE #3
RX
RX
RX
TX
... RX
... RX
...
... RX
...
TX
RX
IO Status
TX
RX
IO Status
TX
RX
IO Status
...
N
PROCESS
To Mitigation Device
 𝑇𝐿 — The delay time from IO changed to generating
Answer package. IO status could be changed at any
𝑇𝑀𝑆 — The transmission delay on the fiber from master time during the two Queries. The worst case is
to the first Slave node, 0.6 µs for 120 m
𝑇𝑄 +delay from IO port to answer package generate
time; the best case is delay from IO port to answer
𝑇𝑆𝐷 — The delay time for transceiver on FPGA, 0.3 µs
package generate time. So 𝑇𝐿 is from 0.3-4.3 µs
𝑇𝑆𝑆 — The transmission delay on the fiber between two  𝑇 — Master Processing time, 1 µs
𝑀𝑃
adjacent nodes, 75 ns for 15 m
 N— The number of slave nodes in one group,
𝑇𝑃 — Package length time, 0.25 µs for 40 bytes
maximum is 8
 𝑇𝑄 — Query Command Period, 4 µs




Y. Wu, March 2014 MPS Workshop - 05D, Slide 6
FPS Response Time Calculate
Slave 2#
Slave 1#
Master
...
IO change
IO change
N...
...
PROCESS
Output to
Mitigation Device
𝑅𝑒𝑠𝑝𝑜𝑛𝑠𝑒 𝑇𝑖𝑚𝑒 = 𝑇𝐿 + 𝑇𝑀𝑆 + 𝑇𝑆𝐷 + 𝑇𝑃 + 𝑁 − 1 2𝑇𝑆𝑆 + 𝑇𝑆𝐷 + 𝑇𝑀𝑃
The worst case is 9.6 µs
The best case is 5.6 µs
The average is 7.6µs < 10 µs
Y. Wu, March 2014 MPS Workshop - 05D, Slide 7
Reference
 [1] T31201-SP-000040-FRIB Accelerator Machine Protection System
Requirements
 [2] T30401-TD-000227-FRIB Machine Protection System Architecture
and Interfaces
Y. Wu, March 2014 MPS Workshop - 05D, Slide 8
Questions?
Y. Wu, March 2014 MPS Workshop - 05D, Slide 9