Harmonic Modeling of a Diode-Clamped Multilevel Voltage Source Converter for Predicting Uncharacteristic Harmonics

Abstract EN

In response to the growing demand for medium- and high-power trends, multilevel voltage source converters (VSCs) have been attracting growing considerations.

One of the widely used VSCs are the diode-clamped multilevel VSC (DCM-VSC).

As these converters proliferate, their harmonic impact may become significant.

Nevertheless, a harmonic model for the DCM-VSC is currently lacking in the literature.

In this paper, the ABCD matrix, mapping the input harmonics to the output harmonics of DCM-VSC, is derived.

As the matrix is formulated in the time-domain, the output harmonics are exact and do not suffer from harmonic truncation errors.

As the paper will demonstrate, the derived ABCD matrix can be easily applied to a microgrid system and users can easily predict all the uncharacteristic harmonics when a microgrid is subjected to various conditions of imbalance.

In addition to all the results being validated with those of PSCAD/EMTDC, the computation time of the proposed method is in contrast much shorter.