X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 1 [X] Return-Path: Sender: To: lml Date: Sat, 09 Dec 2006 00:09:22 -0500 Message-ID: X-Original-Return-Path: Received: from smtp104.sbc.mail.mud.yahoo.com ([68.142.198.203] verified) by logan.com (CommuniGate Pro SMTP 5.1.3) with SMTP id 1655820 for lml@lancaironline.net; Fri, 08 Dec 2006 16:08:51 -0500 Received-SPF: none receiver=logan.com; client-ip=68.142.198.203; envelope-from=elippse@sbcglobal.net Received: (qmail 97707 invoked from network); 8 Dec 2006 21:08:29 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=sbcglobal.net; h=Received:X-YMail-OSG:Message-ID:From:To:Subject:Date:MIME-Version:Content-Type:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE; b=jX0+Jr8YcbnhVRCivKcSFXk46QtsiHIBla2zp5KPTcfRsL69WH6VM5AlBX9fShzwxbZ/jssB4sx9LUbP72iNqgYAfBCa9LgSGpW+k4cHk0ZgPW0+YqGFNTnL/CbqhyYNMnKUwgPkyBI4AsC4qtyedB9cRKvb3x5H1u2JOomuDfA= ; Received: from unknown (HELO Computerroom) (elippse@sbcglobal.net@75.5.198.107 with login) by smtp104.sbc.mail.mud.yahoo.com with SMTP; 8 Dec 2006 21:08:29 -0000 X-YMail-OSG: Uc4T7IsVM1lmHDxECw8lUrsw._zfhrWSe7gyaxfSJVgWsXZclMBV9XQcL1.2YpXWO2UkD9h31GiUB3OckdSj2YMEigsbAv_sW2VxPgYJlepLi7tVSh01EFDkie0BWr6gSJk1_IBWYDASGDQ- X-Original-Message-ID: <000901c71b0d$0173f590$6bc6054b@Computerroom> From: "Paul Lipps" X-Original-To: "Marv Kaye" Subject: Over-excitability X-Original-Date: Fri, 8 Dec 2006 13:08:14 -0800 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0006_01C71AC9.EBB980A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2962 This is a multi-part message in MIME format. ------=_NextPart_000_0006_01C71AC9.EBB980A0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable I wasn't aware that some of the alternator-regulators were given to the = wobblies, over-excitability, or instability if not presented with a = battery as the load. My alternator puts out 6 cycles per revolution per = each phase. With a 3:1 drive ratio, and full wave rectification, that = gives about 1.5kHz per phase at 2500 rpm, which, with the phases = interleaved, should only give about 14% p-p ripple around the DC level. = I would think that there is enough input capacitance in the avionics = attached to the buss to smooth this out without the closed-loop system = going into oscillation. I designed my own PWM regulator with = automatic-reset, series-OV protection, and I tested it into different = loads with no instabilities. I guess the alternator's field inductance = could drive a slow-responding regulator into the heebie-jeebies! ------=_NextPart_000_0006_01C71AC9.EBB980A0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
I wasn't aware that some of the = alternator-regulators were=20 given to the wobblies, over-excitability, or instability if not = presented=20 with a battery as the load. My alternator puts out 6 cycles per = revolution per=20 each phase. With a 3:1 drive ratio, and full wave = rectification, that gives=20 about 1.5kHz per phase at 2500 rpm, which, with the phases interleaved, = should=20 only give about 14% p-p ripple around the DC level. I would think that = there is=20 enough input capacitance in the avionics attached to the buss to smooth = this out=20 without the closed-loop system going into oscillation. I designed my own = PWM=20 regulator with automatic-reset, series-OV protection, and I tested = it into=20 different loads with no instabilities. I guess the alternator's field = inductance=20 could drive a slow-responding regulator into the=20 heebie-jeebies!
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