SPS Partial Economy 1 J. Wenninger BE-OP-SPS April 2009 The partial economy team: S. Page, M. Jonker, S. Cetour Cave, L. Pereira, J.C. Bau, I. Kozsar, E. Carlier

What is the aim partial economy? 2 Switch dynamically from a nominal to a reduced pulse on SFT cycles (for the moment) in the absence of beam after the first injection to save power.

EDF Energy Prices 3 During FT period ~ 20 Euro/MWh Cost of 1 minute of SPS running (summer):  SPS main dipoles at their limit of 39 MW :13 Euro.  SPS total consumption of ~ 80 MV :26 Euro.

SPS power consumption 4 CycleLength (s)Dipoles (MW) Quadrupoles (MW) Energy consumption (kWh) SFTLONG SFTLONG eco CNGS LHCFAST LHC Note : total SPS consumption ~ 80 MW When we switch to partial economy we save ~230 kWh, i.e ~ 5 Euro/cycle.

5 SIS BIC CIB.BA1.S1 Set SW interlock Emergency Dump Trigger emergency dump SPS Mains Switch to economy SPS partial economy event flow SX.APECO t = inj ms t = inj ms

SIS economy tree 6 SIS triggers economy mode when SPS_ECONOMY_MODE = RED = FALSE

SIS economy conditions 7  The SIS tree involves 4 tests that are OR-ed:  Test 1 : TRUE if the BCT intensity is larger than 5 x10^10 p.  Test 2 : TRUE if the BCT acquisition time field is larger than 150 ms (wrt first injection).  Test 3 : TRUE if the main dipoles are NOT pulsing.  Test 4 : TRUE if the main quadrupoles are NOT pulsing.  All 4 conditions must be FALSE to go to economy, i.e.: The BCT intensity is smaller than 5 x10^10 p. The BCT acquisition time is less than 150 ms (wrt first injection). The main dipoles are pulsing. The main quadrupoles are pulsing.  The conditions are evaluated 400 ms after the start of the SFT cycle (200 ms after injection). If SIS decides to switch to economy it:  Sends a SW interlock to the BIC in BA1, waits 10 ms, resets the SW interlock.  Triggers the LTIM which in turn triggers the economy event generation.

Protections 8  If any data is missing  NO ECONOMY.  SIS triggers economy only on SFT* cycles.  Delay protections: o The ROCS system does not accept a economy request after 1200 ms. o The economy event can only be triggered:  During the first BP (1.2 s) of a cycle – in place.  From the two SPS SIS servers and one test server.  Due to the fact that SIS is based on JAVA and that JAVA is not ‘real-time’, there is no guarantee on the time when the actions are triggered.  We have observed additional delays of up to ~800 ms due to the JAVA Garbage Collectors (GC) – in the process of being optimized (GC parameters).  There may also be occasional delays due to CMW (set commends). The timing issues are under investigations.

Diagnostics 9  SIS tree.  SIS alarm.  XTIM “XTS.APECO-XTIM” can be used to monitor to event SX.APECO  used to log the economy cycles.  SPS ring interlock monitor program was upgraded to monitor the economy and indicate it on the main panel. Sw interlock economy Economy detected

Timing details 10 SW permit to FALSE during economy (ms in the cycle)

Help 11 This presentation can be opened from the help menu.