Table 5 Test results of 5th-order total harmonic distortion of customized signal (256 points)
Fundamental frequency (Hz) | Peak to peak (mVpp) | Custom distortion (%) | FFT harmonic analysis method (%) | Error (%) | Digital quadrature detection method (%) | Error (%) | Method error comparison (%) |
|---|---|---|---|---|---|---|---|
150 | 2688 | 7.14 | 7.11 | 0.46 | 7.17 | 0.34 | − 0.12 |
350 | 2432 | 30.28 | 30.19 | 0.28 | 30.30 | 0.07 | − 0.21 |
750 | 2377 | 15.38 | 15.34 | 0.30 | 15.43 | 0.32 | 0.02 |
1150 | 1662 | 35.76 | 35.61 | 0.44 | 35.93 | 0.46 | 0.02 |
1550 | 2688 | 10.97 | 11.02 | 0.45 | 11.03 | 0.52 | 0.07 |
1950 | 2759 | 15.43 | 15.50 | 0.42 | 15.48 | 0.33 | − 0.09 |