Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an e

Post by docnjoj » Nov 09, 2017 12:50 pm

Just bought one of those Wang boosters to try on my trike. I have a Cute 100H and a 36 volt Luna battery. I got it from Hong Kong so it will take a while to arrive but 23 USD shipped. Thanks for all of your testing efforts.
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E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an e

Post by wturber » Nov 10, 2017 1:30 am

amberwolf wrote: The problems arise under one of two conditions:

If teh controller's LVC is higher than the battery's voltage at that point, the controller will shutdown. If the controller's LVC is lower than the battery's voltage will ever be, there's no problem there.

If the battery's BMS HVC is lower than the battery's voltage at that point regen current is flowing into it, it will shutdown the output, disconnecting the controller from the battery. Probably it will reenable the output shortly after this, once the voltage drops below HVC. If the regen voltage is never higher than the battery's HVC voltage, it's not a problem.


These things aren't normally an issue with a controller and battery that are rated to work with each other. Like a 36v battery on 36v controller, or 48v b/c, etc.
Got it. Thanks.

I should have sketched things out. If I had, it would have been clear that the regen power must go through the controller. It's just been a while since I hooked everything up.

It seems clear that any attempt at regen with a boosting converter will introduce more complications that using it to begin with resolves. If you really need/want regen, then a booster like I'm using is not going to be the way to go.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an e

Post by docnjoj » Nov 15, 2017 5:17 pm

The regen problem that you state certainly makes sense. It will not occur on my trike due to the geared motor with freewheel. I am waiting for Banggood shipping to get it here. Probably by the slow plane.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by eCue » Nov 18, 2017 12:41 pm

I would like 5 of those 36v 4.4AH packs what a good deal , best battery deal around. unfortunately I also have a 48v system so would need a new controller but I like its 20A 48 and 64v output spec hate to ditch it to buy a battery pack.

So to get a affordable 2nd booster pack have plan to make a 55.5v 5 or 6AH battery using 5 or 10 of the 11.1v 3000 or 5000mah RC lipo batteries then I'll have a hot pack for speed testing and to help with bridging distances on treks.
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 18, 2017 10:52 pm

eCue wrote:
Nov 18, 2017 12:41 pm
I would like 5 of those 36v 4.4AH packs what a good deal , best battery deal around. unfortunately I also have a 48v system so would need a new controller but I like its 20A 48 and 64v output spec hate to ditch it to buy a battery pack.
Well, that's the whole point of having the voltage converter. You can run pretty much whatever voltage battery pack you want and then dial in the voltage your controller wants. I use 54v for my 48v controller.
eCue wrote:
Nov 18, 2017 12:41 pm
So to get a affordable 2nd booster pack have plan to make a 55.5v 5 or 6AH battery using 5 or 10 of the 11.1v 3000 or 5000mah RC lipo batteries then I'll have a hot pack for speed testing and to help with bridging distances on treks.
And the problem I see with the RC lipos is that their voltages don't always match up well with standard controller voltages and cutoffs. I've thought about putting a light geared hub on my road bike, and using Lipos for the power and a Boost Converter to deal with the non-standard voltages. The idea would be to keep everything light and keep the road bike feel. The question is whether the 2lb weight of the converter will negate the weight savings that the Lipos bring.

BTW, today I went on an extended trip of about 42+ miles. I used seven of the 36v 4.3 Ah packs and they handled it fine. I ran out of time charging and wasn't quite fully charged (voltage at around 41.5v) when I started, and still had leftover power (voltage at around 35.8v) when I finished. I did make it a point to cruise at more moderate speeds - not much over 20mph unless going downhill - just to be safe. In hindsight, I probably could have gone faster and still finished with some charge left.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by eCue » Nov 19, 2017 3:04 am

Im a efficiency nut it would kill me to lose energy through up converting the voltage. .

I do like that a small 5AH lipo pack will be easy to carry and provide enough power to run test at higher voltages as well as provide a good distance enhancer for longer runs.

I put off buying more batteries for a while instead yesterday picked up a set of old stock mid 90's clip on aerobars new old stock made by Rito .

Price $30 with a apparent distance gain of 50% at 35 kmh ( yet to be tested ) this according to number crunching from a time trial web sites info then cross referenced with the ebike motor calculator.

Enough of distance dreams .. I'll get back on track

For running oddball voltages I would need to use a inline watt meter to monitor the discharge rate and voltage drop. Those RC battery watt meters would work well with it as really just need to monitor its voltage.
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by LewTwo » Nov 19, 2017 7:13 am

Thanks for posting this. Using this I technique I might be able to use my older 36V packs as spares for my current 52V volt system. So I had to go look up the boost converter:
https://www.amazon.com/Wangdd22-Convert ... B01N528JFH

By any chance are you Wanda's husband?
The more I learn the more obvious the immensity of my ignorance becomes.
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 19, 2017 11:54 am

eCue wrote:
Nov 19, 2017 3:04 am
Im a efficiency nut it would kill me to lose energy through up converting the voltage.
Well, my thinking was that any losses to converter efficiency could be easily compensated for by either adding a pack or going a tad bit slower. I'm not going to lose any sleep over a 6% or so loss, nor do I care about adding a pound or two to the bike.

And frankly, I really wonder how much loss there really is. That booster NEVER seems to get warm. Ever. The motor gets warm. Heck, the LED "DayMaker" knock-off light I'm testing right now is getting really warm at about 130 F. But the converter always seems to be at ambient temperature.

My take on this system was pragmatism. I can add battery modules easily if range is an issue. But right now, I seem to have plenty of range with seven charging the cells to 4.1 volts. I may start charging to 4.05 volts as my standard with the occasional topping off to 4.2 to help keep things balanced.

My concern with adding the boost converter has been reliability. So far the only reliability issue has been the screw/clamp connectors. I had one come loose on one occasion. I think the trick is to check and recheck a few times until the copper in the wires is well compressed. I suppose I could have added connectors as well.

But to be clear, I'm not trying to talk anybody into using a boost converter. There are clearly pros and cons. The ideal is a system with purpose made, well matched components. I'm just trying to relay my experiences so that others can make more informed decisions. The upshot for me is that I was able to purchase 1600 watt hours of battery capacity for a little more than $200 and can use them with my 48v system as a newbie who really didn't understand yet which controllers would work with his kit LCD, motor, etc. Of course now that I know more, I could change out my controller to a 36v (pseudo-sinewave?) which would let me chuck the converter and add regen. That would be a simpler and more efficient system that would save on brake wear. But it would also drop my top speed by about 5mph.
Last edited by wturber on Nov 19, 2017 1:06 pm, edited 1 time in total.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 19, 2017 11:55 am

LewTwo wrote:
Nov 19, 2017 7:13 am

By any chance are you Wanda's husband?
Which Wanda? <joke> Yes, I have a wife with that name. :^)
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by eCue » Nov 19, 2017 12:11 pm

I never looked into the losses incurred by increasing voltage they may well be lower then the losses associated with down converting voltages. As its not producing much heat means its not losing much energy alright. That's good to know thanks for relaying that
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by sn0wchyld » Nov 19, 2017 4:37 pm

nice write up - im thinking of using one as a 'booster' for my current 48V commuter - works fine on 12s but could easily wire one of these in to boost the voltage when I want a little more top speed, using a relay to cut in/out as needed and get the voltage up to 14s territory. Debatable if its worth the trouble but ive got one of the boost converters already so might be worth a shot.

Also thinking about getting some of those 10s 4.4ah packs available on ebay, using a boost converter would make for an easy booster pack to almost any higher voltage pack, with the built in BMS's protecting the booster automatically. Would allow for much higher power too, given the main battery pack would take all the load, and the booster pack would just recharge them at ~1200w.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by eCue » Nov 19, 2017 10:11 pm

I said I wasn't going to buy batteries for a few months but that did not last long. Had a look on fleabay and found the best deal ever (for me) on batteries. Lipos to be exact cheap ones to me exacter.
I'm not sure how the website feels about linking to commercial sales so I feel better leaving the title of the item for those who are curious the listing was ~ 12V 20000mAh Li-ion Super Rechargeable Battery Pack ~

Edit I just canceled the order as they only output 2.4 amps , I suspect they are fraud cells
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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by amberwolf » Nov 20, 2017 1:38 am

wturber wrote:
Nov 18, 2017 10:52 pm
And the problem I see with the RC lipos is that their voltages don't always match up well with standard controller voltages and cutoffs.
Well, the packs are available in different series configurations. Most commonly 2s, 3s, 4s, 5s, and 6s, from the pack labels I've seen myself and in pics. Between them you can make about any "ebike compatible" pack you want.

For instance, a 36v controller is usually looking for a 10s pack two 5s packs in series make that.

A 48v controller is usually 13s (most will also work with a 14s, "52v" pack). Two 5s and a 3s in series make that. Or a 6s and a 4s and a 3s.


The one thing I would recommend is building them into a good containment box, because while fire isn't all that common with them it does happen, and often unexpectedly, and for the most part quite catastrophically. :( But I'm paranoid about fire (even though the housefire I had had nothing to do with batteries or even electricity).

I've used a 7.62 ammocan for 14s2p, made from 4x 6s packs and 2x 2s packs; it all just fits inside the can with wiring/etc, with notches in the can for wires to come out under the lip of the lid (and enough room for hot gases to come out if fire does happen, without (hopefully) allowing oxygen back into the ammocan to feed the fire at the source).

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 20, 2017 2:46 pm

amberwolf wrote:
Nov 20, 2017 1:38 am
wturber wrote:
Nov 18, 2017 10:52 pm
And the problem I see with the RC lipos is that their voltages don't always match up well with standard controller voltages and cutoffs.
Well, the packs are available in different series configurations. Most commonly 2s, 3s, 4s, 5s, and 6s, from the pack labels I've seen myself and in pics. Between them you can make about any "ebike compatible" pack you want.
Sure. You could do that. But now you have more total packs, more wiring, less flexibility if a single pack misbehaves, less flexibility in brand choice (Multistar have a rep - I think - for being less volatile and lower priced) and less flexibility in taking advantage of pricing specials. Also, I'm not sure how well these lipo packs with different voltages will gang charge. If you gang charge, then I'd think you'd need packs with matching amphour ratings - right?. If so, then finding the right brand, voltage and amphour rating could get complicated. More packs could also make individual balance charging of packs a bigger pain in the behind. And then there's the issue of taking advantage of special pricing where you can get certain packs (that may not combine optimally for certain voltage outputs) at substantially lower pricing on sale.

When I've been thinking about Lipos for a light road bike, my thoughts have been toward two large packs or four medium-large packs at most.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by docnjoj » Nov 27, 2017 9:38 am

Hmmmmmmm............Still waiting for mine to show up from Banggood. For an extra 10 bucks I could have had it in 2 days from Amazon. Penny wise and pound foolish.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 27, 2017 12:45 pm

docnjoj wrote:
Nov 27, 2017 9:38 am
Hmmmmmmm............Still waiting for mine to show up from Banggood. For an extra 10 bucks I could have had it in 2 days from Amazon. Penny wise and pound foolish.
otherDoc
Funny. I paid the premium price on Amazon and got mine quickly. Later, I was wishing I had taken my time and saved a few bucks. I guess the grass is always greener. ;^)
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by docnjoj » Nov 28, 2017 9:04 am

Roger that! Banggood asked me to wait 2-3 more days, so apparently they actually shipped the thing.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by docnjoj » Nov 29, 2017 4:56 pm

Well I broke down and bought the Amazon one. It arrives Friday. If the Banggood one shows up I may have the chance to try parallel boosters, but I really don't see the need. If your fan never goes on in Phoenix, then I don't see the need to parallel. My battery is only 10s5p. In fact I may leiminate the fan for the winter and butt the heat sink against my steel frame. Neater install and might be enough for 60-70F weather. Maybe not in the summer as it runs 95F here.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 29, 2017 6:47 pm

docnjoj wrote:
Nov 29, 2017 4:56 pm
Well I broke down and bought the Amazon one. It arrives Friday. If the Banggood one shows up I may have the chance to try parallel boosters, but I really don't see the need. If your fan never goes on in Phoenix, then I don't see the need to parallel. My battery is only 10s5p. In fact I may leiminate the fan for the winter and butt the heat sink against my steel frame. Neater install and might be enough for 60-70F weather. Maybe not in the summer as it runs 95F here.
otherDoc
Mine is drawing a little more that 1200 watts and delivering a bit less than that. So the only reason to parallel them other than curiosity is if you need more wattage. I've been curious about paralleling two, but the more I've read the more I'm convinced it is probably not a good ideal. I think they need to be synced to each other and it is unlikely that this grade of device either has that ability or could be made to have it easily. I would like to be able to give my controller its full 26A peak power, but I doubt that 26A will be that much different than the 21A it gets now.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by sn0wchyld » Nov 30, 2017 2:47 am

wturber wrote:
Nov 29, 2017 6:47 pm
docnjoj wrote:
Nov 29, 2017 4:56 pm
Well I broke down and bought the Amazon one. It arrives Friday. If the Banggood one shows up I may have the chance to try parallel boosters, but I really don't see the need. If your fan never goes on in Phoenix, then I don't see the need to parallel. My battery is only 10s5p. In fact I may leiminate the fan for the winter and butt the heat sink against my steel frame. Neater install and might be enough for 60-70F weather. Maybe not in the summer as it runs 95F here.
otherDoc
Mine is drawing a little more that 1200 watts and delivering a bit less than that. So the only reason to parallel them other than curiosity is if you need more wattage. I've been curious about paralleling two, but the more I've read the more I'm convinced it is probably not a good ideal. I think they need to be synced to each other and it is unlikely that this grade of device either has that ability or could be made to have it easily. I would like to be able to give my controller its full 26A peak power, but I doubt that 26A will be that much different than the 21A it gets now.
it'd probably be fine having 2 in parallel - the mechanics of a boost converter necessitates the use of a output diode... so the only issue is if one happens to take notably more load than the other. so long as the settings (mainly, output voltage) are as close as possible to equal that shouldn't be an issue.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by troypi » Nov 30, 2017 5:47 am

Hi wturber, nice setup !
I am currently upgrading my 24V ebike to a 36V brushless kit. However I want to keep my 24V battery instead of buying a 36V one. So I decided to go with the same solution and I ordered a 1200W boost converter. So here is my set up:

Battery :
24V 15AH
Rated Discharging Amperage: 15 Amps
Max Continuous Discharging Amperage: 30 Amps
Maximum Discharging Current: 60 Amps

Controller:
36V
max current 15A +- 0.5A

booster converter:
1200W
max current out 20A

I have a few question about it though, I know it is possible to set the output current of converter, using the little screws, and I would like to limit it to 15A in order to not fry the controller. The converter would get 24V and 22.5A in and 36V 15A out (assuming no loss). How do you control the output current of the converter ? Do you just let the battery shut down when the demand is too high ? I have a LCD display where I can limit the current should I limit it to 15A and let it shut down the controller in case of a too high demand ?

Thanks for your help !

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by docnjoj » Nov 30, 2017 9:44 am

I too agree that parallel ones would probably work OK. You are adjusting voltage with the converter, so amps will come from the battery, controller and motor combination. My controller is max of 18 amps, so the watts are limited. My motor draws limited current, so it should not overload anything. My understanding of these little geared motors is that their efficiency improves with higher voltage. I plan to limit voltage out at the beginning and test at various levels starting around 48 or so volts.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 30, 2017 12:26 pm

Hi wturber, nice setup !
[/quote]
I don't know about "nice", but it is functional. ;^)
troypi wrote:
Nov 30, 2017 5:47 am
I have a few question about it though, I know it is possible to set the output current of converter, using the little screws, and I would like to limit it to 15A in order to not fry the controller. The converter would get 24V and 22.5A in and 36V 15A out (assuming no loss). How do you control the output current of the converter ? Do you just let the battery shut down when the demand is too high ? I have a LCD display where I can limit the current should I limit it to 15A and let it shut down the controller in case of a too high demand ?

Thanks for your help !
I don't know the actual electronics, but conceptually the current draw is determined by the demands of the controller and the capability of the converter and battery. The converter and battery will not supply any more current than the motor controller will demand. So there is no need for any current limiting from the standpoint of protecting the controller and motor. The controller shouldn't draw more than it can handle so long as you don't send it more voltage than it was designed for.

There are two things you'll need to set. The first is the output voltage. For a 36 volt system the output should be set somewhere between 36 and 42 volts. I suggest setting it to something close to 42 volts, but you might even be able to go past 42 volts depending on the particular controller and design.

The other setting is the low battery cuttoff. Normally your motor controller serves this function, but with the booster in the way, you need the booster to do this since the controller will see the boosted voltage and not the actual battery voltage. If the battery has its own protection, then you should probably set the booster to some value lower than the battery's limit cutoff limit. If the battery does not have its own protection, then you need to set the value to around 30 volts for a 10S lithium battery. That would be 3 volts per parallel cell group. Assuming your booster operates the same as mine, that can be tricky because you need a 30v supply to the booster so that you can turn the low voltage cutoff pot until the low voltage cutoff LED lights up. Worst case scenario, you can gently run the battery down to a low voltage in order to do this. But it would be kinder and gentler on the battery to have an external 30v power supply of some kind - like mayby your 24v battery fully or nearly fully charged?
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by wturber » Nov 30, 2017 12:34 pm

docnjoj wrote:
Nov 30, 2017 9:44 am
I too agree that parallel ones would probably work OK. You are adjusting voltage with the converter, so amps will come from the battery, controller and motor combination. My controller is max of 18 amps, so the watts are limited. My motor draws limited current, so it should not overload anything. My understanding of these little geared motors is that their efficiency improves with higher voltage. I plan to limit voltage out at the beginning and test at various levels starting around 48 or so volts.
otherDoc
Well, I don't know much about electronics, but the impression I got from reading a number of posts, articles etc. is that the issue is that the lack of synchronization of the DC pulses can create problems and that in order to be sure that the converters will perform well in parallel, they should be synchronized to each other. But yes, some of the articles did say that it might work. I just don't like the idea of "might work" on a daily commuter. That said, I am curious. If you want to send me your extra when it finally arrives, I'd be happy to experiment. :^)

And yes, your max of 18 amps should be well within the capabilities of one booster. I'm finding mine delivers nearly 22 amps at around 54 volts - if my little power meter can be believed.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
7 x 36v 4.3ah 10s 2P battery packs - Wangdd22 1500W 30A DC Boost Converter delivers 54v and about 1175 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
https://endless-sphere.com/forums/viewt ... =2&t=90369

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Re: Using the Wangdd22 1500W 30A DC Boost Converter on an ebike

Post by docnjoj » Dec 01, 2017 8:57 am

Well mine arrives (for sure) today from Amazon.. The Banggood people are refunding my money, and if their converter actually shows up I'll resend the 23 bucks and have 2. No experiments with just one of them, just try to follow your directions and make it provide a bit of extra boost for hills. They do seem to get steeper the older I get. I will remove the fan from its location shown and either leave it off while I butt the cooling fins to the frame for better heat transfer. I will reinstall the fan to blow parallel to the fins if I need to. Heat checks with a laser thermometer on a regular basis. It is winter here in the sunny south so temps range 50-70F. Best time of the year.
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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