Comparison of Modulation Techniques for a Single-Phase Full-Bridge Photovoltaic Micro-Inverter Considering Reactive Power Capability

authored by

Tobias Brinker, Lennart Hoffmann, Jens Friebe

Abstract

In single-phase photovoltaic (PV) power systems, parasitic module capacitances are a well-known issue, as these create a path for high-frequency leakage currents, which can cause electromagnetic interference (EMI) problems. A common method to achieve a limitation of these currents is the harmonization of the common-mode (cm) voltages generated by the modulation of the inverter. The objective of this paper is to provide an overview of the switching states and corresponding cm-voltage waveforms of unipolar modulation techniques for full-bridge (FB) inverters and to identify advantageous modulation schemes. The reactive power switching states are also considered. For the investigations, a modified output filter is used. Further optimization using symmetric half-bridges and asymmetric half-bridges, utilizing two different types of wide bandgap transistors, are discussed in terms of thermal performance and parasitic switching node capacitances. Inverter prototypes of both variants are used for verification and performance analysis.

Organisation(s)

Institute of Drive Systems and Power Electronics

Type

Conference contribution

Pages

841-846

No. of pages

6

Publication date

2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Renewable Energy, Sustainability and the Environment, Energy Engineering and Power Technology, Electrical and Electronic Engineering

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1109/ecce47101.2021.9595845 (Access: Closed)