A Novel Analytical Time-Domain Calculation Method for the Weighted Total Harmonic Distortion (WTHD) in PWM Inverters

Inhalt:
In pulse width modulated inverter systems, a low waveform quality of the inverter output voltages can result in increased losses and/or mechanical vibrations in the electrical machine. To assess the harmonic distortions present in the line-to-line output voltages, the weighted total harmonic distortion (WTHD) is commonly applied in literature. This paper presents a fast analytical calculation method in the time-domain for this quality factor. In addition, the impact of important parameters on the WTHD is investigated for various modulation methods by using the proposed calculation method.