A well designed rotary converter can help some with providing usable 3 phase to a VFD, but a static converter is useless because, unlike an actual motor, the VFD has no inductance to work with for phase shifting.
Steve Stallings > -----Original Message----- > From: Kirk Wallace [mailto:kwall...@wallacecompany.com] > Sent: Tuesday, November 20, 2012 11:00 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] VFD input > > On Tue, 2012-11-20 at 17:28 -0500, Przemek Klosowski wrote: > ... snip > > I can see that, while equalizing the load across the > rectifiers, this > > scheme doesn't help with power variation within the 50/60Hz > cycle, so some > > derating is still called for, I think. > ... snip > > I've given this some thought too. I believe the biggest problem, as > Peter mentions, is the current load on the DC bus capacitors > while there > is no voltage from the single phase. My thinking has been to have a > separate rectifier and capacitors to get DC, then feed that > into the VFD > input, but it's probably cheaper just to buy a larger VFD. > > A rotary or static phase converter should help too, but then > again, it's > cheaper to buy a bigger VFD than build or buy a converter. > > -- > Kirk Wallace > http://www.wallacecompany.com/machine_shop/ > http://www.wallacecompany.com/E45/index.html > California, USA > > > -------------------------------------------------------------- > ---------------- > Monitor your physical, virtual and cloud infrastructure from a single > web console. Get in-depth insight into apps, servers, > databases, vmware, > SAP, cloud infrastructure, etc. Download 30-day Free Trial. > Pricing starts from $795 for 25 servers or applications! > http://p.sf.net/sfu/zoho_dev2dev_nov > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Monitor your physical, virtual and cloud infrastructure from a single web console. Get in-depth insight into apps, servers, databases, vmware, SAP, cloud infrastructure, etc. Download 30-day Free Trial. Pricing starts from $795 for 25 servers or applications! http://p.sf.net/sfu/zoho_dev2dev_nov _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
