A new harmonics/inter-harmonics detection approach based on leakage estimation

A separation approach for harmonics and inter-harmonics detection and measurement in power system which complies with the recommendations of the IEC standard is proposed in this paper. The separation technique is based on the estimation of leakage values at harmonic frequencies caused by all the main inter-harmonics. By subtracting the estimated leakage values from the original spectrum, harmonic components can be obtained without the leakage effect due to the main inter-harmonics. Then the inter-harmonics can be detected by subtracting the harmonics from the original sampled points. Based on the analysis results of simulations and the real world case, it shows that the proposed method is effective to eliminate the calculation errors caused by the spectral interference between harmonics and inter-harmonics even when their frequency differences are less than one frequency resolution.