Mark Nave presented a paper on the topic of optimizing (as opposed to minimizing) cm inductor windings for the desired amount of dm (leakage) inductance at the 1991 EMC Symposium in Cherry Hill. NJ.
”On Modeling the Common Mode Inductor,” pages 452 – 457. He shows dm inductance as a percentage of.cm inductance as a function of angular coverage of windings over the core, among other parameters. -- Ken Javor Ph: (256) 650-5261 From: "James Pawson (U3C)" <[email protected]> Reply-To: "James Pawson (U3C)" <[email protected]> Date: Wednesday, January 8, 2025 at 6:47 AM To: <[email protected]> Subject: Re: [PSES] SV: CM choke / DM inductor Hi Amund, Yes. Flux in the core adds rather than cancelling so there is inductance = 2 x that of a single winding. You already get about 0.5% to 2% of the primary inductance available as DM “leakage inductance” But. The core is ungapped so will saturate with relatively small currents meaning it’s inductance value will change. Google “inductor saturation” All the best James James Pawson Managing Director & EMC Problem Solver Unit 3 Compliance Ltd EMC : Environmental & Vibration : Electrical Safety : CE & UKCA : Consultancy www.unit3compliance.co.uk | [email protected] +44(0)1274 911747 | +44(0)7811 139957 2 Wellington Business Park, New Lane, Bradford, BD4 8AL Registered in England and Wales # 10574298 For inquiries, bookings, and testing updates please send us an email on [email protected] or call 01274 911747. Our lead times for testing and consultancy are typically 4-5 weeks. From: [email protected] <[email protected]> Sent: 08 January 2025 10:34 To: [email protected] Subject: [PSES] SV: CM choke / DM inductor Will this function? … A CM choke were Line2 is coupled the opposite way, and then we have a DM inductor? BR Amund Fra: [email protected] Sendt: 8. januar 2025 10:07 Til: '[email protected]' <[email protected]> Emne: CM choke / DM inductor Just a though …. Is it possible to use a CM choke as a DM inductor? BR Amund This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to [email protected] All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/[email protected]/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: [email protected] Rick Linford at: [email protected] For policy questions, send mail to: Jim Bacher at: [email protected] To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 Virus-free.www.avg.com This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to [email protected] All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/[email protected]/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: [email protected] Rick Linford at: [email protected] For policy questions, send mail to: Jim Bacher at: [email protected] To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1 - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to [email protected] All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/[email protected]/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: [email protected] Rick Linford at: [email protected] For policy questions, send mail to: Jim Bacher: <[email protected]> _________________________________________________ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
