Harmonic Spectrum of Output Voltage for Space Vector-Modulated Matrix Converter Based on Triple Fourier Series

The output voltage of matrix converter (MC) is related to the frequency of input, output, and carrier signals, and these three frequencies are independent of each other. This makes it difficult to give a precise description of the harmonic spectrum with the commonly used methods such as fast Fourier transform (FFT) and the double Fourier analysis. Based on triple Fourier series, this paper proposes an analytical method to determine harmonic components of MC under space vector modulation (SVM). First, combined with the SVM strategy of MC, the expressions of output voltage harmonics are derived. Then the analytical solutions are obtained on the basis of the calculated expressions. From the analytical solutions, the harmonic amplitudes can be determined precisely, and the values of index variables
k
,
p
, and
q
of harmonic frequency
${kf}_{\rm c} \;\pm\; pf_{{\rm{out}}}\pm qf_{{\rm{in}}}$
are confirmed. According to the results, the harmonic distribution characteristics as well as main harmonic components are analyzed. Finally, the feasibility and accuracy of the proposed analysis method is verified by comparative analysis against the FFT results of measured output voltage waveform.