Bachelor of Science

This thesis reports the first ever construction of X-pinch machine at Plasma Radiation Sources Laboratory of NSSE, NIE. The machine consists of three main components: a High Voltage Pulsed Power Supply (HVPPS), a Pulse Forming Line (PFL) and the X-pinch chamber. The major part of this project was to develop a water spark gap based PFL to compress the 2 PS, 200 kV pulse of HVPS system down to 40 ns, 40 kA, 200 kV pulse. This is required as X-pinch are normally operated with 1 W n s pulses.

Dimensions of the PFL were determined after considering the desired electrical parameters of the voltagelcurrent pulse for X-pinch. To cut cost, we designed a novel water based spark gap switch integrated with in the PFL. To do this the breakdown potential of de-ionized water was investigated experimentally by a series of "glass capacitor" based breakdown tests. A PFL was successfully developed with pulse rise time of approximately 35-40 ns.

For electrical diagnostics, a capacitive voltage probe was made for initial measurements of the HVPS. A V-dot probe was later constructed so as to allow us to measure the voltage across the spark gap in the PFL. Calibration against the Tektronix probe shows a calibration factor of 115.8 kVN. A Rogowski groove was also made to allow measurement of the current flowing through the wires in the X-pinch chamber.

Firing at 12kV on the power supply yields an output voltage of 180 kV with pulse duration of approximately 2 PS. Current recorded was 17 kA, implying that impedance higher than the intended 5 D impedance. The setup in the X-pinch chamber was hence modified to reduce the impedance contribution from load. The X-pinch was operated with 15pm gold and 5pm tungsten wires. The time integrated optical imaging confirms the X-pinch formation. The X-ray emissions from the device are investigated using photo-conducting diamond and photodiodes. The signal so far confirms the presence of extremely ultra violet radiations. Investigations to use X-pinch device as a radiography source are undergoing at present.