Characterization of the Balcones 60 MJ Pulsed Power Supply Circuit Parameters

The Center for Electromechanics at The University of Texas at Austin is presently working to complete the start-up testing of the 60 Megajoule (MJ) Balcones Homopolar Generator (HPG) Power Supply. Six identical homopolar generators ( HPG' s) are utilized to produce megamp current pulses for use in industrial welding and electromagnetic launch technologies (900 MW generators a lone; 10 GW generators with power conditioning). An integral part of the start-up is the determination of each generators' electrical circuit impedance. The theoretical premise, test procedures and equipment used to determine the HPG and connecting copper bus circuit parameters of equivalent capacitance (C), inductance (L), and resistance (R) are presented. Consideration is given to the aspects of equivalent capacitance modeling of the HPG. Also discussed are the effects of armature reaction and current magnetic diffusion skin depth on the determination of the values of R, L, and C.