Searching for high power buck converter! - Page 1
Forum section: electronics / beginners

author: rks96
author_rank: Contributor
timestamp: February 03, 2021, 09:10:21 pm
content: Can anyone provide links to buck converter with wide input voltage 10V (lower is better) to 75+V and high current (15A preferably 20+A) and a current limit feature.Closest I have come ishttps://www.aliexpress.com/item/32813562301.html?spm=a2g0o.productlist.0.0.7ec160efFFpsP2&algo_pvid=635ab75e-080a-4d82-9c1f-130b7079ea00&algo_expid=635ab75e-080a-4d82-9c1f-130b7079ea00-42&btsid=0bb0624316122836961848900e066a&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_, but I would prefer something less "smart" with multi turn potentiometers.Another buck converter is thishttps://www.aliexpress.com/item/1005001858143883.html?spm=a2g0o.productlist.0.0.75cb2a1at72xZ0&algo_pvid=887bd745-c9fe-4ae2-871d-a8c540660817&algo_expid=887bd745-c9fe-4ae2-871d-a8c540660817-2&btsid=0bb0623916123862884525025efd79&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_, but lowest input voltage must be less than 10v (12 might be ok)There is cheap high power boost converterhttps://www.aliexpress.com/item/32828748704.html?spm=a2g0o.productlist.0.0.24713f1e20QzRP&algo_pvid=548287fd-983f-41bd-8973-af724df76495&algo_expid=548287fd-983f-41bd-8973-af724df76495-0&btsid=0bb0622d16123863558761607ea732&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_, but I can't find similar power buck alternative.I am too dumb to build one myself, but I could follow schematic if there is one that fits my needs.Thanks for reading.

author: Terry Bites
author_rank: Super Contributor
timestamp: February 04, 2021, 05:06:28 pm
content: Explain. Why do you need to cover such a wide input voltage range?What output voltage do you want at maximum output current?

author: rks96
author_rank: Contributor
timestamp: February 04, 2021, 06:39:10 pm
content: Actually found answer:https://powermodule.aliexpress.com/store/515737?spm=a2g0o.detail.100005.1.67e54f71BVf2YdMy goal is to try to make universal charger and maybe even implement MPPT by tapping in feedback with Arduino. If Arduino can fully control voltage limit and current limit I can program my own charging algorithms ect. The solution that I found allegedly already provides MPPT. The high input voltage requirement was because my solar panel open circuit is 40+V but most buck converter max input is limited to 40V.Also, I found this project that adds MPPT to first (DROK) buck converter from my first post using UART connection.https://github.com/opensolarproject/OSPController/wiki/Step-1-Parts-List#new-now-supports-multiple-power-supplies

author: Cata Lin
author_rank: Newbie
timestamp: April 19, 2021, 07:32:20 am
content: I have a remote location where I spend sometimes my weekends, there is no electricity and I found too OSPController mentioned by rsk96. I have 2 photovoltaic panels, each one has output voltage open circuit 41.3 Vdc, I connected them in series so in ideal sunlight these can deliver 82.6 Vdc. I use a DROK DKP6012 SMPS buck, the spec for this PSU is 75 Vdc input voltage. I checked the main parts for the buck converter, MOSFET, diodes, caps, all are rated for 100 Vdc, so they should handle well my 82.6 Vdc.Also the OSPController project mentioned that DROK DKP6012 can handle this extra voltage well.When I tested first time the setup, all worked fine, my panels supplied 73 Vdc, I charged 1.5 kW in my batteries.A weekend ago, the panels were able to supply 78 Vdc and I had a nasty surprise to see that input voltage at the output, somehow the N channel MOSFET died (MPN is IPP045N10N3G from Infineon) and output was not regulated anymore.I found here on the forum that someone did a little bit of reverse engineering on DROK DKP6012 PSU (https://www.eevblog.com/forum/projects/modifying-drok-buck-converter-for-computer-control/) but I wonder if someone can help me with more details on which parts / functional blocks can limit the input voltage at 75 Vdc on this PSU.Can be the driver block for the MOSFET? Can be the feedback loop? Can be the PSU buck block for the control block (microcontroller PCBA)? If someone has already a schematic for this PSU, it will be great, thanks!