A modular multilevel generic pulse-waveform generator for pulsed electric field applications

摘要

High voltage (HV) pulses are used in pulsed electric field (PEF) applications to provide an effective electroporation process, a process in which harmful microorganisms are disinfected when subjected to a PEF. Depending on the PEF application, different HV pulse specifications are required such as: the pulse-waveform shape, the voltage magnitude, the pulse duration, and the pulse repetition rate. In this paper, a generic pulse-waveform generator (GPG) is proposed, the GPG topology is based on half-bridge modular multilevel converter (HB-MMC) cells. The GPG topology is formed of four identical arms of series connected HB-MMC cells forming an H-bridge. Unlike the conventional HB-MMC based converters in HVDC transmission, the GPG load power flow is not continuous which leads to smaller size cell capacitors utilization, hence smaller footprint of the GPG is achieved. The GPG topology flexibility allows the controller software to generate a basic multilevel waveform which can be manipulated to generate the commonly used PEF pulse-wave forms. Therefore, the proposed topology offers modularity, redundancy and scalability. The viability of the proposed GPG converter is validated by MATLAB/Simulink simulation and experimentation.