Study on pulse power supply by using pulse forming network modules toward intense X-ray source

Summary form only given. For observing interior of dense plasmas, intense, point-spot X-ray source is generated by X-pinch technique¹. Required parameter of the pulse generator is the rate of current rise 10¹² A/s, i.e. 100 kA of current and 100 ns of current rising time².To generate X-ray source by using X-pinch system, PFN module3 was used, having the advantages of holding high peak current, simple fabrication, and so on. The circuit topology of the PFN module through circuit simulations has been optimized, and three-stage LC-ladder of PFN is suitable for the table-top power supply for X-pinch. The inductance component included in the generator is strongly affected to the rate of current rise. In order to reduce the inductance of the X-pinch system, we evaluate the inductance and the rate of rise, experimentally. The PFN modules were coaxially arranged in octagon plates, and 48 PFN modules can be connected to drive the X-pinch. The PFN module consists of a three-stage LC-ladder circuit, which 73 nH of the inductance and 2700 pF of the capacitance. The discharge device has a coaxial configuration to reduce the inductance. The load current flowing through the inductance measured using a Rogowski coil, contained in the device was determined by comparison between the calculated results with Alternative Transients Program-Electromagnetic Transients Program (ATP-EMTP)4. The rate of current rise obtained was 1.7 x 1011 A/s. From these experiments, the electrode inductance of 65 nH was estimated from the results calculated by the ATP-EMTP. The charging voltage to achieve the target rate of current rise is evaluated to be about 60 - 80 kV.