In the power electronics field, the movement that the EMI noise standard is revised is being carried out by IEC. This revision also affects electronic equipments using switching power supplies, and there is a possibility that they can not respond to conventional electronic equipments. In the frequency range of the new standard (below150 kHz), it is essential to take measures against noise from the fundamental wave with the highest noise level. In this paper, we will investigate measures to apply frequency spreading to the frequency range and measurement condition of the new standard, and to minimize the size and increase in cost of electronic equipment.
