Search found 316 matches

by mateusleo
Oct 21 2017 12:26am
Forum: Battery Technology
Topic: Gaozhao Charger Investigated (non-OEM from China)
Replies: 29
Views: 3581

Re: Gaozhao Charger Investigated (non-OEM from China)

I came back to this topic 3 and a half years after my first post on it, and after some progress on electrical engineering, I decided to pay more attention to the charger's circuit. I figured out that the input rectifier can be transformed into a voltage doubler, and so fix my problem about the unava...
by mateusleo
Oct 21 2017 12:18am
Forum: Battery Technology
Topic: I bought the cheapest 48V 10+Ah battery on Aliexpress
Replies: 11
Views: 1109

Re: I bought the cheapest 48V 10+Ah battery on Aliexpress

Some chargers have internal trimpots to adjust output voltage, you could check on that.

Enviado de meu Redmi 3S usando Tapatalk
by mateusleo
Oct 19 2017 5:07pm
Forum: E-Bike Technical
Topic: Modify 220 V Gaozhao charger to 110 V
Replies: 0
Views: 256

Modify 220 V Gaozhao charger to 110 V

I have this 220 V charger, but here on my region mostly outlets are 127 V, in fact, I had to install a 220 V outlet just to use this charger. So today I decided to open it and I figured out that the rectifier in the input could be transformed into an voltage doubler, so even though the grid power is...
by mateusleo
Sep 16 2016 9:54am
Forum: Battery Technology
Topic: DIY BMS Help
Replies: 8
Views: 1099

Re: DIY BMS Help

If you're budget limited, building your own BMS will not help. Although it is a fun exercise (speaking from both personal and professional experience). Don't bother with capacitive or switched inductors, way too complicated and unless you use old laptop cells or hobby lipo (bad idea) your pack will...
by mateusleo
Sep 16 2016 9:50am
Forum: Battery Technology
Topic: DIY BMS Help
Replies: 8
Views: 1099

Re: DIY BMS Help

I think you might find it hard/expensive to make a discrete circuit to switch the capacitors and drive the switches from a ground referenced microcontroller. I would be looking at the existing chips for active balancing using inductors such as the EMB1428Q . There's a chance this chip could be adap...
by mateusleo
Sep 14 2016 8:32pm
Forum: Battery Technology
Topic: DIY BMS Help
Replies: 8
Views: 1099

DIY BMS Help

Hello folks, Me and some friends, along with a teacher, have been porjecting an eletric fsae car. We received resources to buy the motor, controller, tires and suspension, but not enought money for battery and BMS, so we'll have to do our own. The main problem is that we have no experience, but we t...
by mateusleo
Nov 21 2015 10:19pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Yeah, it seems like N-channel. Just be careful because it has no isolated package, so you can't simply mount all the fets on the same chunk of metal heatsink unless you use some kind of isolant between the body and the heatsink and use plastic screws to screw it on because the package is directly c...
by mateusleo
Nov 21 2015 7:15am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Hey thanks for the transistor suggestions. I think I will go with the IRFB3077. It has very low Rdson very high current and voltage handling capabilities. Also very good thermal resistance compare to the others. Just to confirm it is an N-channel mosfet correct? Yeah, it seems like N-channel. Just ...
by mateusleo
Nov 20 2015 4:37pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Heatsink is pretty easy, not that i have any experience, but as big as you can fit seems fine haha. Haha that's what I would like to do but it's not an option, It wouldn't look too good in my thesis without any calculations, + my lecturer has already told me this haha. So I have to know the size vi...
by mateusleo
Nov 20 2015 4:24pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

I see your mosfet choice handles up to 55V. It seems a bit too low, since a fully charged LiFePO4 (48V - 16S) pack will output 59,2 V hot off the charger and drop to 57,6 later. Which exceeds your fet maximum Vds rating. Now that you say that I will charge my battery to see what voltage it goes up ...
by mateusleo
Nov 20 2015 4:16pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

I see your mosfet choice handles up to 55V. It seems a bit too low, since a fully charged LiFePO4 (48V - 16S) pack will output 59,2 V hot off the charger and drop to 57,6 later. Which exceeds your fet maximum Vds rating.
by mateusleo
Sep 29 2015 4:48pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

The microcontroller can do much more than convert the dc into 3 phases. In fact, you could use to to calculate speed, energy spent, theres plenty of things you could do since you are programming it yourself. Are you still going to use a CVT? If so, could also use the controller to control a strong ...
by mateusleo
Sep 28 2015 7:56pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Hey Guys I'm back :) Sorry for the delay but I was really busy with work this summer (+laziness) and all I did was ordered the parts, now the actual work will begin. The 48V 1kW Motor: rsz_20150928_135639-min.jpg rsz_20150928_135706-min.jpg The 48V 15aH battery: rsz_20150928_135809-min.jpg rsz_2015...
by mateusleo
Sep 23 2015 3:00pm
Forum: E-Bike Technical
Topic: spark when plugging battery to controller
Replies: 3
Views: 417

Re: spark when plugging battery to controller

Its not dangerous for you or for the bike systemm but it will degrade the connectors (but takes a really long time to make deal significantly damage).Don't worry about that
by mateusleo
Aug 21 2015 6:52pm
Forum: E-Bike Technical
Topic: ADAPTTO Controllers - new functions discussion
Replies: 153
Views: 18790

Re: ADAPTTO Controllers - new functions discussion

Bla bla bla bla bla. All i wan't to see is more powah! :twisted: :twisted:
by mateusleo
Aug 11 2015 4:18pm
Forum: E-Bike Technical
Topic: Multiple battery chemistry in one pack
Replies: 45
Views: 3363

Re: Multiple battery chemistry in one pack

If you don'nt have any circuit to control it, the less resistive pack, read newer, will discharge fastter (current flows thought the less resistive path), but not probably not noticeable. Also, simply paralleling them will simply divide current thought it as they were resistors, most of the current ...
by mateusleo
Aug 08 2015 10:00pm
Forum: General Discussion
Topic: Trinary
Replies: 27
Views: 2470

Re: Trinary

3-way logics would certanly increase capabilities of logic circtuis, but don't think on theory only, pratical issues come right on: first of all, when reading a disk, such as a DVD, the laser shoots an light to the disc section, reflection means 1, no reflection means 0. Its just simple this way, ha...
by mateusleo
Aug 08 2015 9:55pm
Forum: E-Bike General Discussion
Topic: Upgrading discs to 203 mm - worth it?
Replies: 25
Views: 2957

Re: Upgrading discs to 203 mm - worth it?

Its more likely you have something lose or slightly out of place causing the vibrations. My little knowledge on bicycle mechanics leads em to belive its not the rotor.
by mateusleo
Jul 26 2015 9:17pm
Forum: Large EV General Discussion
Topic: Cushman based build
Replies: 122
Views: 21374

Re: Cushman based build

Really cool project!!
by mateusleo
Jul 16 2015 8:52am
Forum: Motor Technology
Topic: Motor inductance discrepancy between phases
Replies: 10
Views: 846

Re: Motor inductance discrepancy between phases

According to what Miles stated above, spin the motor a bit and measure again so we can have more info
by mateusleo
Jul 16 2015 8:47am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Ok guys, So I have made a diagram on how the pack will be connected and wired both as a supply and for charging. The info is all in the picture below. First off for future reference is the pack in this conflagration 2s3p? The pack should be 44.4V 15ah correct? When using the pack should the balance...
by mateusleo
Jul 15 2015 10:43am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

So you have 6 packs of 6S batteries? The safest easy way is with two 6S chargers. One charger per 6s parallel group, being powered by two different power supplies. Make sure they are large chargers that can handle charging 333 watt packs each. I use BC 168 chargers to balance my packs, an some 30 a...
by mateusleo
Jul 14 2015 8:33pm
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Firstly I think you mean 15 hours to charge the whole pack with the first charger. But I am running the pack at 44.4V 15ah 3 paralell banks of 2 6s batteries in series. So the charging time would be halved, however in that configuration would I be able to charge them all at once? You have to pay at...
by mateusleo
Jul 14 2015 9:14am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Ok guys, So here is my attempt to build my own HK Pack. Please tell me if it is viable and if I need any thing else. The battery I will use is this: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=35828 I will buy 6 of these, pairing up 2 in series and the connecting them togethe...
by mateusleo
Jul 11 2015 7:09am
Forum: E-Bike General Discussion
Topic: Custom BLDC Controller Closed Loop
Replies: 77
Views: 6791

Re: 1-3 kW E-Bike Build Custom Speed Controller and CVT

Hello again Guys, DDK you are a gold mine :) :lol: Thanks for responding. So after some more research regarding battery packs it seems that I'm gonna go with the 48V 15Ah chinese pack at 500$. It is reasonably priced and it comes with everything such as a charger and I assume a BMS as well. It is c...