LANSCE Digital Low Level RF Upgrade

TL;DR

This paper discusses the deployment, performance, and challenges of the digital low level RF upgrade at LANSCE, highlighting its adaptability for future enhancements and multi-beam operations in a legacy system environment.

Contribution

It presents the implementation and operational experience of a digital LLRF system in a legacy accelerator, demonstrating its adaptability and performance improvements.

Findings

30 of 53 digital systems deployed as of 2022

Successful multi-beam and multi-energy operations achieved

Demonstrated adaptability with recent high-power RF upgrade

Abstract

Incremental upgrades of the legacy low level RF (LLRF) equipment-50 years for the Los Alamos Neutron Science Center (LANSCE)-involves challenges and problems not seen with new and total replacement opportunities. The digital LLRF upgrade at LANSCE has deployed 30 of the 53 required systems as of September 2022. This paper describes the performance of the digital upgrade, current status, and future installations along with the technical challenges, including unexpected challenges, associated with deploying new digital systems in conjunction with legacy analog equipment. In addition, this paper discusses the operational details of simultaneous multi-energy beam operations using high energy re-bunching, beam-type specific set points and simultaneous multi-beam operations at LANSCE. The adaptability of the digital LLRF systems is essential as the design is able to accommodate new control and beam parameters associated with future systems without significant hardware modifications such as the expected LANSCE Modernization Program. This adaptability of the digital LLRF technology was recently demonstrated with the Module 1, 201.25-MHz high-power RF upgrade completed in 2021.