LS1 Report: injectors 2.0

Launched in 2009, the Accelerator Controls Renovation Project (ACCOR) will come to an end this year. It was brought in to replace the approximately 450 real-time control systems of the LHC injector complex, some of which were based on technology more than 20 years old.


One of the approximately 450 real-time systems that have been modified in the ACCOR project.

These systems, which use special software and thousands of electronics boards, control devices that are essential to the proper functioning of the injectors – the radiofrequency system, the instrumentation, the injection kicker system, the magnets, etc. – and some of them were no longer capable of keeping pace with the LHC. As a result, they urgently needed to be upgraded.

"In 2009, after assessing the new technology available on the market, we signed contracts with Europe's most cutting-edge electronics manufacturers," explains Marc Vanden Eynden, ACCOR Project Leader. We then quickly moved on to the integration phase: DAQ boards, microprocessors and electronic crates. We had to integrate these new solutions into the injector environment and then redesign the new software and hardware architectures for each system we were renovating."

It took 14 months of hard work to replace all the control systems, during which a team of 10 people assisted by a host of engineers disconnected and dismantled 450 systems and then re-assembled and reconnected them all again. "There were no manuals for some of the critical systems," says Marc Vanden Eynden, "and the people responsible for designing these systems were obviously not around any more… So it was hard to tell which cable was for what! As a result, we had to do some 'reverse-engineering' to work out how the system had been built. Because once we had dismantled it there was no turning back."

Staff from the BE-CO and TE-EPC groups carrying out the integration tests on the control system for the Antiproton Decelerator (AD).

The teams tested the new systems as they were being installed, but without a full restart of the machines it was impossible to get an overall view. But replacing these systems has affected all levels of control, from the equipment in the tunnel to the high-level programmes used in the Control Room. Consequently, it is essential to carry out full integration tests to check every link in the chain.

So this year, with more and more injectors having been restarted, the teams have been able to carry out more comprehensive testing. In Linac 2, the control systems for the source and power converters have already been successfully tested. "The testing will become more critical from April onwards, because we'll be testing dozens of systems on several injectors in parallel. All tests are due to be completed by the end of August. Then, from the point of view of the control system, we'll have 'new machines' that are ready for the forthcoming LHC runs," concludes Marc Vanden Eynden.

Meanwhile, elsewhere

At the LHC, the consolidation of the high-current splices between the superconducting cables of the electrical feed boxes (DFBAs), which is part of the SMACC project, has been completed. The teams are currently busy closing and connecting the DFBAO and DFBAN shuffling modules. The installation of the shunts in the arcs is also practically complete.

The electrical quality assurance testing (ELQA) carried out after the flushing of Sector 6-7 has not brought to light any new non-conformities, which is very good news. The cooling of this sector should therefore start at the beginning of May.

At the PS and the PS Booster, the hardware tests have started - they will finish in May. We would like to congratulate the teams for all their hard work in keeping the work on schedule.
At the SPS, the campaign to replace the irradiated cables has been completed this week. The reinstallation of the line will begin next week. The start of the machine closure phase is still scheduled for 27 June.


by Anaïs Schaeffer