| Title |
FRIB Beam Power Ramp Process Checker at Chopper Monitor |
| Authors |
- Z. Li, E. Bernal, J. Hartford, M. Ikegami
FRIB, East Lansing, Michigan, USA
|
| Abstract |
Chopper in the low energy beam line is a key ele-ment to control beam power in FRIB. As appropriate functioning of chopper is critical for machine protec-tion for FRIB, an FPGA-based chopper monitoring system was developed to monitor the beam gated pulse at logic level, deflection high voltage level, and in-duced charge/discharge current levels, and shut off beam promptly at detection of a deviation outside tolerance. Once FRIB beam power reaches a certain level, a cold start beam ramp mode in which the pulse repetition frequency and pulse width are linearly ramped up becomes required to mitigate heat shock to the target at beam restart. Chopper also needs to gen-erate a notch in every machine cycle of 10 ms that is used for beam diagnostics. To overcome the challeng-es of monitoring such a ramping process and meeting the response time requirement of shutting off beam, two types of process checkers, namely, monitoring at the pulse level and monitoring at the machine cycle level, have been implemented. A pulse look ahead algorithm to calculate the expected range of frequency dips and rises was developed, and a simplified mathe-matical model suitable for multiple ramp stages was built to calculate expected time parameters of accumu-lated pulse on time within a given machine cycle. Both will be discussed in detail in this paper, followed by simulation results with FPGA test bench and actual instrument test results with the beam ramp process.
|
| Funding |
Work supporting the U.S. Dept. of Energy Office of Science under Cooperative Agreement DE-SC0023633 |
| Paper |
download THMBCMO26.PDF [0.813 MB / 5 pages] |
| Slides |
download THMBCMO26_TALK.PDF [0.384 MB] |
| Poster |
download THMBCMO26_POSTER.PDF [3.024 MB] |
| Cite |
download ※ BibTeX
※ LaTeX
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※ EndNote |
| Conference |
ICALEPCS2023 |
| Series |
International Conference on Accelerator and Large Experimental Physics Control Systems (19th) |
| Location |
Cape Town, South Africa |
| Date |
09-13 October 2023 |
| Publisher |
JACoW Publishing, Geneva, Switzerland |
| Editorial Board |
Volker RW Schaa (GSI, Darmstadt, Germany); Andy Götz (ESRF, Grenoble, France); Johan Venter (SARAO, Cape Town, South Africa); Karen White (SNS, Oak Ridge, TN, USA); Marie Robichon (ESRF, Grenoble, France); Vivienne Rowland (SARAO, Cape Town, South Africa) |
| Online ISBN |
978-3-95450-238-7 |
| Online ISSN |
2226-0358 |
| Received |
04 October 2023 |
| Revised |
10 October 2023 |
| Accepted |
13 October 2023 |
| Issued/td>
| 24 October 2023 |
| DOI |
doi:10.18429/JACoW-ICALEPCS2023-THMBCMO26 |
| Pages |
1256-1260 |
| Copyright |
 Published by JACoW Publishing under the terms of the Creative Commons Attribution 4.0 International license. Any further distribution of this work must maintain attribution to the author(s), the published article's title, publisher, and DOI. |
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