Since the device can effectively improve the power factor of the power load, reduce the line loss, improve the actual load capacity of the transformer, and have significant energy-saving effect, at the same time, the use of specific reactors in the system can also effectively prevent harmonic amplification, effectively absorb most of the harmonic current, so that the total harmonic voltage anomaly rate limit and each harmonic current content limit meet the national standard. To achieve the purpose of harmonic control.