System harmonic impedance measurement method based on rotating current phasor

The invention discloses a system harmonic impedance measurement method based on rotating current phasor. The method includes 1) successively injecting each harmonic current to the system with a three-phase harmonic current generator; 2) changing the phase angle of the injected harmonic current with the step length of 0.1 degrees to obtain a certain amount of harmonic current samples correspondingto the harmonic currents at different phase angles, screening the maximum and minimum values, and calculating the system harmonic impedance; 3) changing the amplitude of the injected harmonic currents, and repeating step 1) and 2) to obtain a sample of the harmonic impedance; and 4) based on the harmonic impedance sample, obtaining the average value of the harmonic impedance, removing the point where the error is too large in the sample, and repeating step 4) until the error meets the precision requirement. The method can adapt to the variation of the harmonic impedance caused by the variationof the load and suppress