Performance of switched mode AC power supply

In order to enhance the injection performance, the AC power supplies of the booster synchrotron of SRRC must output high quality current waveform. To ensure smooth and efficient injection of the booster ring, the phase jitter of the AC power supplies current must be small than +/-4ns. A new AC power supplies are constructed and employ IGBT modules operating at higher switching frequency than the old GTO-based system. This will not only improve the phase jitter produced but also increase the operating efficiency of the power supplies. The measured dynamic range of the 10 Hz sine wave current output of the new AC power supplies is better than 75dB; and phase jitter is less than +/-4ns. The improved performance is illustrated in the paper.