Conceptual Design of a Marxipeaker, Direct-Drive, Inductive Voltage Adder (IVA) for Radiography Applications

We have performed a conceptual design of a 6 MV IVA with cells that are directly driven from individual Marx/peaker circuits. The present design assumes use of the RITS IVA cell parameters, driving a negative polarity vacuum coax, and a load impedance of 40-60 ohms. However, the approach scales to at least 16 MV, and is adaptable to positive polarity systems over a range of cell designs and load impedances. In contrast to the more familiar PFL-driven IVAs, this system topology close-couples a compact Marx, coaxial water peaking capacitor and output switch with a single IVA cell. The peaking circuit effectively isolates the Marx series inductance from the load for the first 50-100 ns of the output pulse, thereby providing the desired pulse characteristics for the application. This is accomplished while utilizing COTS components, easily serviceable configurations and mature technologies throughout.