Trim Power Supplies for the Duke Booster and Storage Ring

The on-going Duke storage ring upgrades and the development of a new booster synchrotron injector require more than 100 units of high performance unipolar and bipolar trim power supplies in the current range of - 15 A to + 15 A. However, most of the trim power supplies on the market do not deliver two critical performance features simultaneously: a high current stability and a low current noise. An in-house trim power supply development program has been put in force to design, fabricate, and test low cost linear power supplies with current stability about 100 ppm and current ripples less than 100 ppm in a broad band. A set of unipolar power supplies (0-12 A) have been designed, fabricated and successfully tested. Since August, 2004 they have been used in storage ring operation with excellent performance. The prototype of bipolar power supplies (±15 A) has been designed and tested as well. The main design principles and the performance results of both unipolar and bipolar supplies have been presented in this paper.