Title: Optimisation of switching frequency of three-phase four-wire inverter under different dead time

Authors: Fuzhuan Wu; Mengna Chen; Sheng Peng; Shengjun Wen

Addresses: Department of Electric and Information Engineering, Zhongyuan University of Technology, No. 41 Zhongyuan Road, Zhengzhou, Henan Province, 450007, China ' Department of Electric and Information Engineering, Zhongyuan University of Technology, No. 41 Zhongyuan Road, Zhengzhou, Henan Province, 450007, China ' Department of Electric and Information Engineering, Zhongyuan University of Technology, No. 41 Zhongyuan Road, Zhengzhou, Henan Province, 450007, China ' Department of Electric and Information Engineering, Zhongyuan University of Technology, No. 41 Zhongyuan Road, Zhengzhou, Henan Province, 450007, China

Abstract: Aiming at the selection of inverter switching frequency and the harmonic problem of the dead time in reality, an optimal method for switching frequency of three-phase four-wire inverters considering the dead time to reduce the total harmonic distortion (THD) was proposed. Firstly, the output sinusoidal pulse width modulation (SPWM) wave was analysed by using double Fourier transform and Bessel function, and the spectrum of SPWM with dead time was obtained. Secondly, the relationship between the THD of the output voltage and the switching frequency was analysed. The study found that there is an optimal switching frequency to minimise the output voltage THD. Thirdly, the linear Lagrangian interpolation method was used to fit the formula for selecting the optimal switching frequency with different dead time. Finally, a three-phase four-wire inverter test prototype based on the TMS320F28335 control chip was built, and the effectiveness of the proposed method was verified through experiments.

Keywords: switching frequency; dead time; three-phase four-wire inverter; total harmonic distortion; THD.

DOI: 10.1504/IJAMECHS.2022.10046463

International Journal of Advanced Mechatronic Systems, 2022 Vol.9 No.4, pp.219 - 226

Received: 11 Aug 2021
Accepted: 20 Jan 2022
Published online: 31 May 2022 *