P.83. A.N.Dovbnya, V.V.Zakutin, N.G.Reshetnyak, V.P.Romasko, I.A.Chertishchev (Kharkov Institute of Physics and Technology, Kharkov, Ukraine)
A PULSED MODULATOR TO ENERGIZE THE SECONDARY- EMISSION ELECTRON SOURCE OF THE TECHNOLOGICAL ACCELERATOR
Experiments were made to investigate a pulsed modulator intended to energize the elec- tron accelerator based on the secondary-emission electron source. The accelerator with a great pulse length (8 - 40 mks) and a pulse repetition rate up to 10 Hz is designed for ma- terial-surface treatment. To form long pulses in the modulator (with reservoir capacitor discharge through a step-up transformer), the nonlinear properties of the pulse-transformer core material are used, while the top of the pulse is formed through summation of a short spike and a flat-topped long-duration pulse. At a load resistance of 4300 Ohm; a voltage pulse with a spike amplitude of ~ 150 kV and a flat-topped pulse with an amplitude of ~ 130 kV of ~ 16 mks duration and a repetition frequency of 3 Hz were obtained. During formation of the beam with a current of ~ 100A the amplitude of the flat part of cathode voltage made ~ 100 kV.
Dr. Valeriy Zakutin: email@example.com
P.84. A.A.Pachkov, P.A.Bak (Budker Institute of Nuclear Physics, Novosibirsk, Russia) HIGH VOLTAGE DECOUPLED HIGH-CURRENT POWER SUPPLY
10 kW power supply (PS) with smooth adjustment of a load current from zero up to 2 is described. Depending on the load requirements operating modes with stability of a load current from 5% to 0.1% and long-term instability of 0.01% are possible. Power mains isolation is up to 35 kV. PS includes the high-frequency inverter, transformer-rectifier module and the control block. The high-frequency inverter is performed on progressive ZCZVS-PS-FB (Zero Cur-rent Zero Voltage Switching - Phase Shifted - Full Bridge) to- pology. It provides a full range load regulation with the minimal power losses. Dynamic losses of the inverter switching do not exceed 6%. The step-down transformer secondary winding has the form of a solid turn that allows to receive low leakage inductance and high working frequency. Rectifier block is based on the current symmetric doubler circuit. Total power losses of the transformer-rectifier module is about 15%. Thus, the high- frequency conversion and doubling of a load current allow to reach high power and low weight parameters of the device. The power supply control circuit is realized on an CPLD base by "ALTERA" firm. The intellectual algorithm of inverter management provides soft switching in a full range of load variations and precision stabilization of a load current. The remote control is carried out through the CAN-interface. Oscillograms of a power supply operating modes are presented, the received results are discussed.
Aleksey Aleksandrovich Pachkov: A.A.Pachkov@inp.nsk.su