Short circuit test - complete analysis for the dense plasma focus

The static impedance of the capacitor bank and external connections of the dense plasma focus has a great importance in the device performance 1,2 . Previous works used approach formulas to find the machine static parameters 3 . In this paper a complete RLC circuit analysis was performed to find exact formulas for the static impedance of the machine 4,5 . Rogowski coil was used to measure the current waveform in a short circuit test for KSU-DPF. A nonlinear base shift of the integrated signal that expresses the current was noticed to deform the current waveform 6 . This error was corrected by introducing three methods; digital filters, peak averaging method, and baseshift extrapolation. The three methods succeeded in removing the baseshift with different precisions. The RLC analysis used also to find an accurate calibration factor for Rogowski coil. A MathCAD program was developed to calculate the required parameters from the current waveform. The program treated the current as sinusoidal waveform modulated by decaying exponential function. The program was applied to find the impedance for the KSU-DPF. The static inductance for the machine was found to be 124.83nH, the static resistance 14.4mΩ, and Rogowski calibration factor 4.76×10 4 .