A near magnetic field 3D imaging system is developed in this paper. The distance from magnetic field source and the frequency dependency of the magnetic field strength distribution are investigated. As a result, the performance of the proposed system is verified and the specific technique of the effective magnetic field source is examined.電力技術/電力系統技術/半導体電力変換技術合同研究会, 3月8日-9日, 2016年, 九州工業大学 戸畑キャンパス, 福岡県