Abstract

This paper presents a simple Modular Multiphase Multilevel Converter (MMPMC) especially
for the usage in Power Hardware-in-the-Loop Emulation systems. Standard half-bridges connected
to flux compensated chokes are used to build up an inductive voltage divider to form the
multilevel voltage waveform. A modulator with a sorting algorithm is employed to calculate the
switching signals of the particular branches. The selection of the switching states is depending
on the instantaneous branch currents to ensure a symmetrical distribution of the load current
to the branches. A modular and scalable converter system has been engineered, which allows
the generation of a six level voltage waveform with a PWM-frequency up to 100 kHz. The prototype
is controlled by a specifically designed high-performance signal processing system and
offers an output current of more than 100 A. Measurements were performed to evaluate the
proper functionality of the converter.