When systems are tested using these techniques, make sure the latest version of EN61000-3-2 is used, incorporating Ammendment 14.
Previously, simple techniques could be used to modify the input current waveform, and distort it outside the 'special waveform' envelope shown in figure 1 of the standard. This enabled you to use the less-stringent Class A limits. With the incorporation of Ammendment 14, there is no evaluation of the input current waveform to determine the test limit. The application alone will determine the test limit used. ---- Patrick Lawler [email protected] On Tue, 12 Dec 2000 10:03:50 +1100, Jon Keeble <[email protected]> wrote: >You may be interested in a paper > >Power Factor Correction for AC-DC Converters with Cost Effective Inductive >Filtering > >by > >W.Wölfle Convertec Ltd., Wexford, IRELAND >W.G.Hurley National University of Ireland Galway, IRELAND >S.Arnold Enserb Bordeaux, FRANCE > >To quote the conclusion: > >This paper presents a new, simple and cost effective solution >for the power factor correction of the input current of a >switch mode power supply, which meets the IEC limits on >harmonic distortion. A sloped air-gap inductor, which adapts >its inductance values to the input current conditions of the >power supply, is used to shape the current to comply with the >limits for harmonic distortions as defined in EN61000-3-2. > >It is shown that using a classical inductor design, the filter >inductor is too bulky, whereas the volume of the sloped air-gap >choke is as small as the switching transformer of the >power (e.g.100 kHz) supply. In fact, the volume required is >not bigger then that required for an active PFC circuit, but at >a fraction of the cost. > >The .pdf is too large to post, but I'll mail a copy to the first ten >callers ... > >Seasonal Greetings > >----------------------------- >Jon Keeble >Fairlight >Hardware Engineering Manager >8977 9931 >[email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
