Harmonic power and loss distribution in an inverter-fed permanent magnet synchronous machine drive : identification of harmonic power components and their relationship with distortion indicators from measured waveforms
Szafraniec, Szymon (2026)
Diplomityö
2026
School of Energy Systems, Sähkötekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2026061167151
https://urn.fi/URN:NBN:fi-fe2026061167151
Tiivistelmä
This thesis investigates harmonic power and loss distribution in an inverter-fed permanent magnet synchronous machine drive. The objective was to segregate harmonic power components from measured voltage and current waveforms and to evaluate the relationship between harmonic power content and commonly used waveform distortion indicators.
The study is based on frequency domain analysis of measured waveforms obtained from silicon-carbide based inverter-fed PMSM operating under no-load conditions. Fundamental and harmonic power components were separated, and the resulting harmonic power content was compared with several distortion indicators, including total harmonic distortion (THD), weighted THD (WTHD), crest factor, and harmonic current RMS.
The results showed that harmonic power can be successfully identified from measured waveforms and separated from the fundamental power component. The harmonic power content remained relatively constant across the investigated operating range, indicating that it is primarily determined by inverter switching behaviour and the resulting harmonic voltage spectrum. Among the investigated distortion indicators voltage WTHD and harmonic current RMS showed the strongest correlation with harmonic power during the no-load measurements. When considering full operating range of the PMSM, harmonic current RMS exhibited the most consistent relationship with harmonic power content.
The findings suggest that harmonic current RMS can be used as a practical indicator for estimating harmonic power content in inverter-fed electrical drives. The proposed approach provides a basis for future harmonic loss assessment and efficiency analysis of converter-fed drive systems.
The study is based on frequency domain analysis of measured waveforms obtained from silicon-carbide based inverter-fed PMSM operating under no-load conditions. Fundamental and harmonic power components were separated, and the resulting harmonic power content was compared with several distortion indicators, including total harmonic distortion (THD), weighted THD (WTHD), crest factor, and harmonic current RMS.
The results showed that harmonic power can be successfully identified from measured waveforms and separated from the fundamental power component. The harmonic power content remained relatively constant across the investigated operating range, indicating that it is primarily determined by inverter switching behaviour and the resulting harmonic voltage spectrum. Among the investigated distortion indicators voltage WTHD and harmonic current RMS showed the strongest correlation with harmonic power during the no-load measurements. When considering full operating range of the PMSM, harmonic current RMS exhibited the most consistent relationship with harmonic power content.
The findings suggest that harmonic current RMS can be used as a practical indicator for estimating harmonic power content in inverter-fed electrical drives. The proposed approach provides a basis for future harmonic loss assessment and efficiency analysis of converter-fed drive systems.