High Accuracy Frequency Detection Method Using 1 to mthHarmonics

This paper proposes the high Accuracy frequency detection method by using 1 to mthharmonics. In the proposed method, frequencies of harmonics are detected, and the sum of them is divided by the sum of these orders. The proposed method improves the frequency detection accuracy by $(\mathrm{m}+1)/(2\sqrt{\mathrm{m}})$ as compared with the conventional method using only the mthharmonic. The improvement of the frequency detection accuracy is derived from formulation and is confirmed by simulation and measurement results.