HARMONIC MEASURING APPARATUS AND INDIVIDUAL OPERATION DETECTING METHOD USING THE SAME, INDIVIDUAL OPERATION DETECTING APPARATUS AND DISTRIBUTED POWER SUPPLY SYSTEM

摘要

To accurately measure a harmonic voltage with simple and inexpensive circuit configuration.SOLUTION: An inverter part 41 outputs a second AC voltage having a low relative harmonic content. An amplitude of Kth cosine and an amplitude of Kth sine of a corrected harmonic voltage are acquired in advance. When the inverter part 41 is interconnected to an electric power system 32, an amplitude of Kth cosine and an amplitude of Kth sine of a harmonic voltage are acquired from a first AC voltage of the electric power system 32. The amplitude of Kth cosine and the amplitude of Kth sine of the corrected harmonic voltage are respectively subtracted from the amplitude of Kth cosine and the amplitude of Kth sine of the harmonic voltage to calculate an actual value of a Kth harmonic voltage after the correction. Step injection is determined using the actual value of the Kth harmonic voltage after the correction.SELECTED DRAWING: Figure 1