Pulsing the Zero Gradient Synchrotron Directly from the Utility Line

The history of extended periods of lost experimental time, due to mechanical and electrical failures in the flywheel motor-generator (M-G) sets used by pulsed synchrotron magnets, indicates a necessity for standby facilities. The idea of pulsing synchrotron magnets directly off the utility lines without interposing a flywheel M-G set has become very active in recent years. Investigations have shown this to be an extremely attractive alternative for the Zero Gradient Synchrotron (ZGS). The switchover, in the event of an M-G set failure, can be made within a matter of hours; the first costs are lowest, operating costs are reduced and reliability is increased; and it can be built in stages from partial energy to full energy capability. The first phase will be to install a 35 MVA transformer capable of pulsing the ZGS to an energy of 9 GeV with a line voltage fluctuation of less than 1%. Low voltage taps will be available for low energy pulsing to study the effects on the utility system. The second phase will provide for bypassing one-half of the rectifier supplies during flattop. This limits the voltage fluctuation to a value consistent with continuous operation. In the full energy phase, a second transformer will be added and the system kVARs will be reduced by switching precharged capacitors.