## 1 Introduction  
For the pulsed electric field treatment of plant cells, pulses with voltages in the range of several 10 kV and currents in the order of at least several 100 A are required. Thereby, the Marx circuit is one of the common configurations for the pulse generator [1]. A basic pulse circuit for one stage of a Marx-type solid-state pulse generator for the generation of unipolar pulses comprises a capacitor, a solid-state switch, and a free-wheeling diode. After closing the switch, the capacitor delivers its stored energy into the connected load. The energy transfer ends if either the complete stored energy has been transferred to the load or the switch has been opened. In the case of an inductive component of the impedance of the attached load, the current may commutate to the current path through the free-wheeling diode. If the switch has previously opened, this prevents the occurrence of an over-voltage across the switch. This basic circuit can be stacked. The charging path can be set up using solid-state switches comprising additional active switches [2]. When charging the stage capacitors in a parallel configuration, the power supply needs to have the characteristic of a current source in order to provide direct control of the charging current. The Marx generator features voltage multiplication according to the number of stages and the voltage stress of each component to be limited to the stage voltage only [3]. Both advantages are achieved by the combination of charging the capacitors in a parallel configuration and discharging them in a series configuration, and, moreover, by adding circuit elements, i.e., inductors or resistors, in between the stages providing a DC current flow during charging and transient insulation during pulse generation. This concept has been varied, in particular with respect to the arrangement of the current path for charging. In [4, 5], pulse circuits with voltage multiplication and resonant charging are described. Both circuits feature circuit elements, i.e., diodes and transformers, providing the required insulation between stages during pulse generation, which are stressed with a pulse voltage which is significantly higher than the stage voltage. Article [6] describes a charging circuit featuring a voltage source with a series resistor and some diodes, which bridge several stages and, hence, need to block more than only the stage voltage. In [7], a pulse transformer is used for distributing the gate signals to the generator's IGBT switches, which needs to be designed to insulate the peak pulse voltage. According to [8], a boost converter configuration acting as a current source and delivering a bipolar output voltage delivers current to the charging path, which is equipped with diodes and MOSFET switches designed to block the stage voltage only. The goal of the investigations described in this paper is to set up a Marx generator with resonant charging and a design with only one actively controlled switch per stage in order to reduce the effort for control circuitry with respect to designs having more active switches per stage. Moreover, this combination allows advantageously for a fine-tuning of the charging voltage using only the single switch per stage in addition to its original use as a pulse switch. The pulse shape can be determined by means of appropriate control of the pulse switches allowing for the generation of arbitrary voltage shapes. Such an operation requires stage capacitors, which are sufficiently large to keep the voltage droop during pulse generation small and, hence, allow the generation of almost rectangular voltage shapes. If the controlled variation of the pulse shape is not important, the pulse shape can be determined by the passive circuit elements of the pulse circuit. In the case of the classic Marx generator, this would be an RLC circuit. The pulse circuit of such an electroporation device comprises the Marx generator, the treatment chamber, and the circuit inductance. The Marx generator serves as capacitance.