Asymptotic time domain evaluation of a single-phase multilevel PWM inverter current quality

Boris Reznikov, Milan Srndovic, Gabriele Grandi, Bexultan Rakhim, Yakov L. Familiant, Alex Ruderman

2015

Closed access Metadata (CSL-JSON)
DOI 10.1109/edpe.2015.7325267
Data confidence 70 medium
How this score is calculated

It is built from checkable properties of the record itself: whether the article has a DOI, how many independent sources confirmed its data, whether the required fields are filled in, and how recent the latest confirmation is. Disagreement between sources and a missing identifier lower it. A value of 80 or above means the record was published without further checking; 60 to 79 means it is published at reduced confidence, with a manual check advisable. A record verified by an editor by hand is never pushed below 90 by a recalculation. This scores our data about the article, not the article itself.

Abstract

This paper addresses theoretical calculation of a single-phase multilevel PWM inverter current Total Harmonic Distortion (THD). Analytical approach introduced in late 1980s for a 2-level inverter is generalized for an arbitrary level count for a single-phase inverter. Though the obtained closed-form piece-wise analytical solutions assume (infinitely) large ratio of switching and fundamental frequencies and pure inductive load, they are practically very accurate for the ratios of (apparent) switching and fundamental frequencies larger than 25-30 and inductance dominated loads. Along with strict mathematical solutions suggested are simple accurate Bessel function approximation and hyperbolic average trend one. The formulas clearly reveal a single-phase PWM inverter current THD dependence on modulation index for an arbitrary voltage level count and are easily modified to cover grid-connected cases.