A modular PFN Marx with a unique charging system and feedthrough

We have developed a reliable, high power Marx generator system capable of operation at up to 550 kV/11 kA with an output flat top of 1 ¿S nominal. The unit can operate at up to 5 Hz for 2 seconds (>30 kW output) from a power supply with a ¿built-in¿ HV section. The Marx section consists of 14 series type C PFNs each with an impedance of approximately 3.5 ohms. The individual PFNs are built so that they are easily removed and modified. With this flexibility, the unit can be adapted to changes in the load such as those due to diode impedance collapse. The HV section of the HV power supply is not only in the Marx oil bath but it is ¿connected¿ to the semiconductor portion of the power supply using ¿air core magnetic flux coupling¿. This technique is as far as we know unique, and it eliminates the requirement for a high voltage or high current wired feedthrough in the system. It also dramatically reduces EMI coupling from the Marx to the semiconductor power supply modulator and the control system. The efficiency of this supply is approximately 80%. In the paper we will discuss the theory of the coupling and the experimental results of operation of the power supply and Marx.