Boost  PFC controller that can  handle square wave mains? - Page 1
Forum section: electronics / general

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 27, 2020, 05:19:11 pm
content: Page 1 of the HiperPFS-3 (Boost PFC controller) datasheet states that it has facility to handle distorted input waveforms from UPS. As such, can the HiperPFS handle the attached square wave type output of an UPS?Would you agree that the lack of Post rectifier bus voltage sensing in the HiperPFS-3 makes it easier for the HiperPFS -3 to handle “square wave mains”?Do you know of any other Active PFC methods/controllers which can handle square-wave-mains?The HiperPFS-3 datasheet:https://ac-dc.power.com/sites/default/files/product-docs/hiperpfs-3_family_datasheet.pdf

author: wraper
author_rank: Unknown
timestamp: December 27, 2020, 05:27:23 pm
content: I assume yes. Because UPS which outputs sine outputs voltage with barely any distortion and will work fine with any PFC controller in regards of input voltage quality..

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 28, 2020, 01:27:19 am
content: Thanks, though i am considering the case of a square wave mains as in the waveform shown in the top post, and how HiperPFS-3 (or any other Boost PFC controller) would handle this?

author: wraper
author_rank: Unknown
timestamp: December 28, 2020, 01:29:30 am
content: Quote from: opampsmoker on December 28, 2020, 01:27:19 amWhat I mean, there is no point mentioning UPS, unless UPS outputs modified sine = square wave.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 28, 2020, 02:23:27 pm
content: If you can modify the UPS or inverter and only intend to use it with electronics, reduce the dead time to something small like 5% and the peak current will be a lot lower, for better efficiency.

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 28, 2020, 04:08:04 pm
content: Thanks, but its customer equipment and we can modify it.We have to handle thesquare wave mains of the top post.I say no Boost PFC controller on the market can handle this....what is needed is a separate non-PFC'd SMPS which just draws from the square wave mains. The Boost PFC stage must be completely switched out and taken out of the game, do you agree?

author: Ian.M
author_rank: Super Contributor
timestamp: December 28, 2020, 04:33:37 pm
content: The datasheet claims (in the section: HiperPFS-3 Additional Features and Changes): "• Square-wave detector feature for improved UPS operation." so it should already be capable of running correctly from your input supply waveform. The only issue will be the lower peak voltage will result in a greater switch current to deliver the same power so you'll need to check you aren't running too close to its limits.

author: nctnico
author_rank: Super Contributor
timestamp: December 28, 2020, 07:23:15 pm
content: Quote from: opampsmoker on December 28, 2020, 04:08:04 pmNo. UPSses are rather common and it makes no sense to put a PFC controller on the market which can not deal with being powered from a UPS.

author: opampsmoker
author_rank: Regular Contributor
timestamp: December 29, 2020, 01:47:34 pm
content: QuoteYes, but most UPS's output a pure sine wave....and of course as you know Boost PFCs can handle that. We need this system to do PFC , and still be able to handle the more rare square wave UPS output, as in the top post.I am certain Boost PFCs cannot properly handle this. PI say they can but skip stating exactly what waveform of UPS they can deal with.....they probably mean a quasi sine which is pretty well sine, just a bit "steppy".

author: wraper
author_rank: Unknown
timestamp: December 29, 2020, 02:19:48 pm
content: Quote from: opampsmoker on December 29, 2020, 01:47:34 pmBS, no cheap consumer UPS which are the most common output pure sine. You will need to pay at least $150 to get a sine wave.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 30, 2020, 04:05:14 am
content: The datasheet says it works with distorted waveforms from UPS and generator which obviously means modified sin/square. There is no point saying you work with true sine wave UPS: they probably have cleaner waveforms than the mains. If that isn't enough for you it also says it has square wave detection for better operation from UPS.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 30, 2020, 01:36:38 pm
content: Quote from: wraper on December 29, 2020, 02:19:48 pmI have seen some for about $100 new, the prices have come down a bit.Depending on the load requirements, you could detect the square or modified sine output of the UPS and automatically switch into a low power mode, for example, reducing CPU/GPU clocks to minimum.

author: wraper
author_rank: Unknown
timestamp: December 30, 2020, 01:41:36 pm
content: Quote from: NiHaoMike on December 30, 2020, 01:36:38 pmExample please.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 31, 2020, 01:59:03 pm
content: Quote from: wraper on December 30, 2020, 01:41:36 pmhttps://slickdeals.net/e/11413755-cyberpower-cp1000pfclcd-pfc-sinewave-ups-system-100-ac-free-shipping

author: wraper
author_rank: Unknown
timestamp: December 31, 2020, 03:25:14 pm
content: Quote from: NiHaoMike on December 31, 2020, 01:59:03 pmAnd if you click the link, it costs $155

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 31, 2020, 10:03:41 pm
content: Quote from: wraper on December 31, 2020, 03:25:14 pmIt was $100 when the deal was posted in 2018.

author: wraper
author_rank: Unknown
timestamp: December 31, 2020, 10:14:52 pm
content: Quote from: NiHaoMike on December 31, 2020, 10:03:41 pmBut you should understand it's a weird way to confirm your point. It's not a normal retail price. In the same way I can say you can buy genuine Hakko 888D for $50.