TRISTAN MR klystron power source

Two types of klystron power sources, Type A and Type B, are in use for the Tristan electron-positron collision ring (main ring). Type A is used to supply power to two klystrons while Type B for a single klystron. A power source consists of separate power supply components for the cathode, anode-heater and focusing/pre-focusing coils of each klystron. For the crowbar switch, an equivalent circuit is used to determine the inflow current and estimates are compared with data. The comparison reveals that the crowbar switch satisfactorily meets the requirements for the protection of the klystrons. The actuation of a crowbar switch will have a rather large effect on other power sources, resulting in various noises. Thus improvements and modifications are required against these noises. Discussion is also made on the control of klystron beam current. Signals obtained through detection of the drive power and the pattern signals (Vc-loop reference signals) are used for controlling the anode voltage. The final part of the report describes an actual case where the actuation of a crowbar switch had a large effect on power sources installed along the Tristan main ring. (Nogami, K.)