“…[3], i.e., for frequency changer with M=2 and main supply frequency of 50 Hz the output frequency of frequency changer will be 25 Hz, the frequency spectrum of the output shown only the odd harmonics with different amplitudes and different phases [4] while the even harmonics had zero magnitude due to even wave symmetry, and harmonic distortion result by the odd harmonics only [5]. One of the important parameters that used to measure the performance in power electronic converters is nth harmonic distortion [6] caused by the each harmonic which can be estimated using where A n represent the amplitude of corresponding harmonic while A 1 represent the magnitude of fundamental, for divide by two frequency changer described above the n th harmonic distortion resulted by apparent harmonics are subjected in Table 1.…”