A HYBRID APPROACH TO UPGRADE HARDWAREFOR THE PROTON STORAGE RING FAST KICKER
T.Ramakrishnan, J.Duran, H.Watkins - Los Alamos National Laboratory, Los Alamos, NM 87545, USAAbstract

The Los Alamos Neutron Science Center (LANSCE) Pro-ton
Storage Ring (PSR) needs precise timing to ensure successful
extraction of the bunched protons. The current control system’s
hardware is obsolete and unmaintainable. The task was to replace
the 1980’s era CAMAC control and timing system for the PSR
extraction kickers. This included a system which halts charging ofthe kickers after a duration without firing to prevent equipment
damage. A hybrid approach was taken to integrate a Berkeley
Nucleonics Corporation (BNC) pulse generator that was controlled
by a soft input/output controller (IOC) and National Instrument (NI)compact Reconfigurable Input/Output (cRIO) IOC. This allowed forflexibility and modularity of the software and hardware
development. This approach built the framework to streamline
robust deployment of hybrid systems and develop a solution for
upgrades of other LANSCE kickers.

Proton Storage Ring

The LANSCE proton storage ring (PSR), Fig. 1, is used to collectand bunch protons. The alignment and frequency of the protons
are changed continuously to keep them inside the ring for multiple
cycles which are then ejected to the Lujan Mark IV target toproduce neutrons which are used in several experiments.

Figure 2: Software and Hardware Architecture for SRFK upgrade

Fast Kicker Purpose & Controls Upgrade

The storage fast kicker (SRFK) system consists of a DC power supply,
a Blumelein that acts as a capacitor, and two plates (SRFK71 andSRFK81), Figure 2, as well as a control system that directs andmonitors certain functionality. The fast kicker system is responsible forextracting the bunched protons from the PSR and sending them down
the beam line towards the neutron producing target.
The control system that was upgraded used an obsolete, 1980’s,
CAMAC form factor. It is worth mentioning that it had no safetymechanisms in place for over charging the fast kicker Blumlein which
is holding the charge that is being provided in a pulsed fashion by a
DC power supply. The newly deployed and functionality advanced
control system utilizes a hybrid approach by using two commercial of
the shelf systems (a) BNC 577 pulse generator, Fig.3, for generating
delayed pulses and (b) NI cRIO, Fig.4, for reading back the status ofan RF switch and keeps track of charging pulses to the Blumlein. The
hybrid approach also extends to the controls software implementing (a)soft IOC to control the BNC 577 and (b) NI cRIO based IOC that has afield programable gate architecture (FPGA)backplane interacting withthe modules for high-speed data acquisition.

Figure 1: Proton Storage Ring with SRFK71 and SRFK81 locations

HYBRID APPROACH

The hybrid approach that was undertaken for this project focusedon establishing versatility for system design by having two simple
approaches to hardware and soft-ware architectures that were both
integrated in the larger LCS framework. The ability to create PVs
using soft IOCs on virtual machines for the BNC 577 pulse
generator and physical IOCs using NI cRIO’s FPGA backplane.
This effort flows well with our long term LANSCE modernization
project that is focused on reducing the number of disparate control
systems to a more unified approach. We used this homogenousapproach principle to incorporate a soft IOC to handle the stream
device input/output control PVs and use an existing deployed cRIO
to handle the readbacks, counters, and set time delays for thepulses.
A hybrid approach by incorporating stream device protocol for BNC
pulse generator accompanied by a soft IOC and an industrial input
output (IIO) using cRIO with a self-contained IOC helped us easily
upgrade the legacy CAMAC system that was used to control theSRFKs for over a decade. The flexibility this approach offers without introducing additional complexity to providing solutions will be
useful moving forward with upgrading control systems at LANSCE
and at other accelerator facilities that rely on the EPICS
architecture.

Figure 3: BNC Pulse Generator

LA-UR-23-30143
Managed by Triad National Security, LLC, for the U.S. Department of Energy’s NNSA.

Figure 4: 8 card NI cRIO