Path: ...!3.eu.feeder.erje.net!feeder.erje.net!usenet.goja.nl.eu.org!weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Don" Newsgroups: sci.electronics.design Subject: Re: power supply idea Date: Mon, 22 Apr 2024 12:57:22 -0000 (UTC) Organization: A noiseless patient Spider Lines: 32 Message-ID: <20240422a@crcomp.net> References: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Mon, 22 Apr 2024 14:57:22 +0200 (CEST) Injection-Info: dont-email.me; posting-host="c77f3f6969b602e4fa67625b28419749"; logging-data="1023266"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18An7kaGvXF9fYD+ii/Y9V2" Cancel-Lock: sha1:hQobXNYPhjFjmtAz9BSXMcb6bMw= Bytes: 2221 John Larkin wrote: > > If one had, say, a 48 volt power bus, you could hang a half-bridge > switcher to ground, and a lowpass filter out. If the drive has duty > cycle n, the output voltage is 48*n. So we have a programmable power > supply with no feedback, which will be stable into any load. > > The load regulation will be mediocre, but we could almost sell it > as-is. > > So now, sense the output voltage and compute the error against the > target, run through a slowish integrator, and tweak the PWM to get > zero output voltage error. Gross transient response is basically the > response of the output filter, with some modest drool from the > integrator. > > We can constrain the influence range of the integrator, just enough to > give the regulation that we need. That limits output swing in case the > feedback is wrong, as one could get from a botched remote sense > connection. > > https://www.dropbox.com/scl/fi/2fysyvkl4eim7vujhaobh/FFINT_PS_1.jpg?rlkey=rug6yi3cgemi9vvbz8apgboqi&raw=1 Is your "spread spectrum" dodad supposed to mitigate EMI? Danke, -- Don, KB7RPU, https://www.qsl.net/kb7rpu There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.