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VESC on 48V 1500W HUB motor

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jordanlow
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VESC on 48V 1500W HUB motor

As for the hardware, I wish to run the hub motor on vesc using hall sensor mode. Due to previous experiment of hub motor on other manufacture product which does not work. Has anyone tried it on hub motor and do I need to add on any hardware which is to limit the maximum potential voltage to the input pin? thanks

sam.vanratt
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Hi jordanlow

My MagicPie3 is build for 50V/30A constant drive and the VESC did show in the few tests I did to be capable of using it even under constant load (friction brake flanched onto the wheel). I let the tests run for about 15 min, until the brake got too hot burning such a high amount of energy (the MP3 is about 85% efficiency at that drive). The VESC was at 45° (FET) with heatsinks on all FETs, so there was still lot of room to fill in. The new VESC6 must be much better at that with lower RDS_on and cooling possible direct on the die instead if plastic covering in the VESC4. I've used only 20kHz switch rate to minimize the load on the FETs.

For my real usage it's limited to 9A at 30V with the same motor which is enough for my daily ride.

Cheers

Sam

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

jordanlow
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Hi, apparently the vesc that i brought which is v4. 12 is damaged due to the 5 to 3.3V regulator shorted between 5V and 3.3V. I would think the microcontroller is damage as well due to 5V supply directly. May I know what is the reason behind this? I set up with 48V 1500W hub motor. Max current drive of 20A, and 13S battery which is at 55V when fully charged. But the battery has built in BMS system which only allow single direction for charge and discharge. 

Jordan

sam.vanratt
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Hi Jordan,

the used (and any) uC is quite sturdy when it comes to misuse, as long as the voltage is not overdriven and not reversed. Shorting +5V and 3,3V should show who's the stronger one as the voltage will only rise when the 3,3V line cannot take more current. The stronger one wins.... and maybe kills anything below (3,3V) him. I'll not try it, but it surely has happened to someone else was well :-(

I do construct charging electronic (and batteries) for a living, but was long as you do not have two lowLoss Diodes (ideal diodes with FETs does not work/help here) and two different poles (Charge + Discharge) there is no way to stop current going both ways. MOST BMS I know of are very simple in design and often stupid as bread. I don't know your battery, but as mentioned: don't expect them to be good. A quite interesting one is the BMS8 from Chargery (which balances always at all time and use capacity chargers which is quite effective instead of burning the energy. The usual PCB with one FET per Cell and diode+transistor+a few resistors (so called window comparators) are far from the task they should do to keep the battery in best health.

Mr. Vedders VESC is cleanly done, but there are a lot of third party mfc's who are (well) not the best of solders or component decision makers. My second VESC was from SCRAMboard and in no way as cleanly made as the original one. That doesn't mean all China products (SCRAM is UK btw.) are not clean made as they do wholesale and some persons solder or align since 40 years; no matter how good I was trained, years of continues experience in the same field decides here. Funnily some solder cables like hell but do not know why different colours were chosen.

Cheers

Sam

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

jordanlow
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Hi, thanks for given answer to my doubt and question. Obvious I brought the VESC 4.12 from third party and as I was desolder the damage component from VESC i notice there are flux residue between the solder pad. It is a good but pricey lesson learned that the battery I used have two different poles which is one for discharge and the other for discharge. I have ald planned to change the BMS system to single port and attempt replace some of the component in VESC. Thanks.

Jordan