1 / 8

Prediction of hysteresis with different squeeze scenarios

Prediction of hysteresis with different squeeze scenarios. P. Hagen November 2010. Hysteresis during squeeze. There are 3 components in the FiDeL model which contribute to hysteresis: PEN - current penetration in the cable filaments ( low currents )

aldona
Download Presentation

Prediction of hysteresis with different squeeze scenarios

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Prediction of hysteresis with different squeeze scenarios P. Hagen November 2010

  2. Hysteresis during squeeze • There are 3 components in the FiDeL model which contribute to hysteresis: • PEN - current penetration in the cable filaments (low currents) • DCMAG - persistent currents in SC magnets • RESMAG – residual magnetisation of materials • DCMAG depends upon the sign of the dI/dt (ramp up or down)We do not know the exact conditions (Δt, ΔI) causing a switch of branch • During the squeeze many magnets around the collision IPs change ramp direction • We assume DCMAG is the dominant source of hysteresis, and for RESMAG, FiDeL gives us in any case only 1 branch; ramp-up (see next slide) • We assume the de-composition of the transfer function is correct (the split between DCMAG and RESMAG is physical and not just a fit!)

  3. Example of TF with hysteresis h not given by FiDeL • Example MQWA, warm magnet with full operational cycle • In FiDeL we model TF only for the ramp-up • The different path for ramp-down is not present in FiDeL • The size of the hysteresis depends upon Imin and Imax

  4. Data sources for following tables • Optics from /afs/cern.ch/eng/lhc/optics/V6.503/IPn • FiDeL TF by circuit • WISE with 3.5 TeV ramp

More Related