Abstract:
At the Duke FEL Lab, we have developed and implemented a new
storage ring control system based upon physical quantities.
Most other operational accelerator control systems are base
on direct controls of various hardware systems, e.g. setting
a power supply current to control a magnet. Such systems
present a raw interface to a very complex accelerator and
need to be supplemented by a high level physics control to
perform sophisticated operations. The new control system at
Duke uses an integrated approach to optimize the overall
system performance, moving many critical high level
functions to the low level realtime system. This system is
designed around physical quantities experienced by the beam,
e.g. magnetic multipole strengths such as the bending angle,
normalized focusing strength (K1), and sextupole strength
(K2), all based upon measured magnetic field data. With this
system, energy ramping and transition between different
operation modes becomes a trivial task. It also allows us to
focus on developing high level controls regardless of the
beam energy. Furthermore, with better understanding of the
storage ring, we can fine tune our control in the low level
to present an invariant virtual machine to the operator,
independent of the beam energy.