Advanced Light Source control system

The Advanced Light Source (ALS) is a third-generation 1-2-GeV synchrotron radiation source designed to provide ports for 60 beamlines. It uses a 50-MeV electron linac and a 1.5-GeV, 1-Hz, booster synchrotron for injection into a 1-2-GeV storage ring. Interesting control problems are created because of the need for dynamic closed beam orbit control to eliminate interaction between the ring tuning requirements and to minimize orbit shifts due to ground vibrations. The extremely signal-sensitive nature of the experiments requires special attention to the sources of electrical noise. These requirements have led to a control system design which emphasizes connectivity at the accelerator equipment end and a large I/O bandwidth for the closed-loop system response. Not overlooked are user friendliness, operator response time, modeling, and expert system provisions. Portable consoles are used for local operation of machine equipment. The solution is a massively parallel system with >120 Mb/s I/O bandwidth and >1500 MIPS computing power. At the equipment level connections are made using over 600 powerful intelligent local controllers mounted in 3U size Eurocard slots using fiber-optic cables between rack locations. In the control room, personal computers control and display all machine variables at a 10-Hz rate including the scope signals which are collected through the control system. Commercially available software and industry standards are used extensively