FGC Upgrades in the SPS

1. FGC Upgrades in the SPS V. Kain, S. Cettour Cave, S. Page, J.C. Bau, OP/SPS

2. Introduction – FGC for the SPS During LS1 the SPS power converter controls framework ROCS was replaced by the more powerful FGCD framework ROCS was relying on obsolete products such as SL_Equipand LynxOS FGC: new standard across the CERN accelerator complex FGCD follows the FGC power converter state model. Function generation and state are coupled together. FGCs will be used by the power converters and RF. RF will have additional RFFG card for more resolution (FGC limited to 1 kHz).

3. FGCD state model

4. FGC states for the main operation of SPS power converters During the main operation of the SPS as a multi-cycling machine, the power converters will be in state CYCLING

5. Other aspects… • Power converters that are connected to the interlock system will remove the permit if not in an operational state: • on_standby or to_cycling e.g. are not operational states. • Automatic polarity switching is supported • Dynamic switching between dipole chain in TI 8 and TT41 not for the time being.

6. FGCD opened the door to significant improvements The new SPS COAST Improvements to SPS Economy All the changes were only possible with some significant upgrade of the injector timing system and LSA for the SPS

7. Concept of the new SPS coast

8. The main features of the new SPS COAST - 1 • A cycle with the same timing user can be “cycling" or in COAST. • The difference is made with the introduction of machine modes in the timing system: CYCLE, COASTPRE, COAST, COASTREC • A single timing table exists for all machine modes for a given timing user. • But the sending of an event is conditioned with machine mode • E.g. if in mode COAST, the beam dump events do not come out • In mode COASTPRE the timing event SX.S-COAST-CTM is sent out. • It is configured in the timing table at the time of a coast plateau. • Upon reception of this event the FGCs and RF freeze their functions.

9. The main features of the new SPS COAST - 2 FGC states in COAST • The FGCs are then in state IDLE. • From then on operation à la LHC. • Trims no more on function, but “actual beam process” • Generated when entering COAST • “Actual beam process”= time slice of function containing single point. • During COAST use NON-PPM property of the FGCs. • In mode COASTREC (= Coast Recover) • Beam dump events are sent out and then the event SX.E-COAST.CTM • SX.E-COAST.CTM sends FGCs to TO_CYCLING • All changes from “Actual beam process” are incorporated into the function For all the different steps we will make heavy use of the SPS sequencer.

10. Improvements to SPS Economy

11. 3 Types of Economy Goal: SPS should not pulse if there is no beam; can be disabled for testing • Full Economy • EDF demand for power consumption reduction or external condition • Will be set on the telegram and FGCs react to it • FGCs will stay on last point of last cycle (=13.5 GeV) • Dynamic Economy • No beam detected by BCTs: generation of timing event • Check implemented in FESA class by OP/SPS • FGCs play special dynamic economy function upon reception of event • Different for different power converters and different cycles • Pulsing on correct dynamic destination only • Concerns power converters associated with the fast extractions and transfer lines for LHC and HiRadMat

12. Full Economy vs. Dynamic Economy Full Economy Dynamic Economy t1 FGC builds dynamic economy function with parameter t1. Corresponds to the time when the economy function should join the original one again.

13. First test results - COAST

14. First Tests & Status of Upgrades • All new timing features are available since March • All power converters in the SPS are now FGC • Almost all features are available • Can test power converter controls in SIMULATION • Still missing: • Upgrade to new timing events • Economy on dynamic destination • Increase of number of points for function to 5000 • Allow dynamic economy if dI/dt != 0, within limits • All missing FGC features will be finished during May • RFFG still under implementation • OP testing not started

15. Sequence Manager – Set cycle “coastable" Rule: only one cycle in supercycle, spare uncoupled “coastable = true” in generation for cycle type

16. Test of COAST – 1 • Request coast on sequence manager: software button

17. Test of COAST – 2

18. Test of COAST – 3

19. COAST – still to be tested/prepared • Concept of “actual beam processes” from LSA • Trim during COAST via LSA and execution of trim with timing event • Incorporation • Sequence to enter and exit COAST

20. First test results - ECONOMY

21. Dynamic Economy - 1 • FESA class: BCTECO running • Triggers timing event SX.APECO-CT if BCT4 or 3 below threshold

22. Dynamic Economy - 2 • Trigger comes fast enough even for the shortest cycles • E.g. LHCPILOT(max time allowed 60 ms after injection) @ 36 ms LHCPILOT SFTPRO @ 36 ms

23. Full Economy Still to come for FGCs: reaction to telegram

24. Other stuff to come • New application to look after FEI interlocks for power converters for fast extraction to LHC and HiRadMat • Sequences • SIS interlock update for FGCs • New application to manage economy

25. Summary • During LS1 the SPS power converter control with ROCS has been replaced with the FGCD framework • This upgrade opened the door for wide ranging improvements and modifications. The most significant changes: • New SPS COAST • Improvements for SPS Economy • To fully exploit the flexibility with the FGCs, new features were necessary in the timing system and LSA • Many of the new features are already available and test results look very promising. • All timing features are available since March and fully functional. • Details are being finalized and testing continues until end of the summer.