• V. Popov, M. D. Busch, S. M. Hartman, S. F. Mikhailov, O. Oakeley, P. W. Wallace, Y. K. Wu
  FEL/Duke University, Durham, North Carolina

A booster synchrotron has been recently commissioned at Duke University as part of the High Intensity Gamma-ray Source (HIGS) upgrade. All dipole and quadrupole magnets are fed by the same power supply in order to facilitate synchronization. A 500kW retired thyristor controlled power supply has been completely rebuilt to provide high accuracy ramping of current in the range between 150A and 700A in a 1.3 sec repetition cycle. Reproducibility of current at extraction energy is better than 0.1% for entire operational range of energy. Conflict of a fast ramping operation and a magnet protection in the case of emergency shutdown was resolved using additional thyristor switches. All trim power supplies involved in ramp have been matched with the main power supply for the time response and voltage range. The injection and extraction schemes require rapidly ramping Y-correctors. The required peak power about 4 kW in these correctors is provided by a combining a low voltage DC power supply and a pulse boosting circuit. We present the challenges of designing and developing booster power supply system. And also we report measured performance and operational experience in this paper.