Design and Metrological Characterization of a Digitizer for the Highest Precision Magnet Powering in the High Luminosity Large Hadron Collider

authored by
Nikolai Beev, Miguel Cerqueira Bastos, Michele Martino, Daniel Valuch, Luis Palafox, Ralf Behr
Abstract

A new digitizer, the HPM7177, which is a fundamental component of the signal chain for high precision measurement of particle accelerator magnet currents, is presented. It was designed to meet the unprecedented performance requirements for new 14 kA and 18 kA power converters (PCs) for the High Luminosity Large Hadron Collider (HL-LHC) project at CERN, particularly in terms of low-frequency noise and stability. To determine accurately the performance of the digitizer, which is on a similar level as state-of-the-art classical metrological equipment, we carried out a thorough characterization using the programmable Josephson voltage standard (PJVS) at PTB-Braunschweig. At its nominal full scale of 10 V , the digitizer has a white noise level of < 175 n V Hz-1/2 , 1/f noise floor ≈ 7e-8 V , and a 12-h peak-to-peak stability better than 2 μ V or 0.2 parts per million (ppm). The static non-linearity from 0 V to +10 V is < 1 ppm and remains stable to ≈ e-7 l evel in 12. The digitizer operates at a fixed rate of 10 k Samples s and can be synchronized externally. Besides qualifying HPM7177 for its application, the characterization reveals important aspects of its operation, as well as some performance limitations.

External Organisation(s)
CERN
Slovak University of Technology in Bratislava
National Metrology Institute of Germany (PTB)
Type
Article
Journal
IEEE Transactions on Instrumentation and Measurement
Volume
73
Pages
1-10
No. of pages
10
ISSN
0018-9456
Publication date
2024
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Instrumentation, Electrical and Electronic Engineering
Electronic version(s)
https://doi.org/10.1109/TIM.2023.3343809 (Access: Open)