Voltage Limits of electronic components

[jlpmedia]

Im thinking about overvolting my bpm2 hub motor by 2x (96v) but i dont want to fry any of the electronics inside of the motor. ive seen people with 144v motors, but is that dependent of brand/mods? Ive already machined a new aluminum gear to replace the nylon gears and i cast a 7600psi plastic gear as a backup if the aluminum gear is too loud/wont hold up to my extreme power requirements...

any help would be greatly appreciated.

 

[xenodius]

Not sure about the bpm2 hub specifically, but most hubs except the Magic Pie and BionX don't have any electronics except for enameled copper and Hall sensors. What you need to worry about is your motor Kv. For any controller without field weakening, doubling the voltage doubles no load RPM and increases load on the motor significantly.

Take care not to overheat.

I saw a video of a guy running a Mac motor at 88.8v/60amps a while back, I think he said he could cruise for about 10 minutes. Cav3 with thermal rollback would be perfect.

Edit: also be sure your controllers FETS aren't outside their limit. 96v is not appropriate for irfb1110.

 

[jlpmedia]

okay thanks. I'm not at all concerned with overheating as my motor is liquid cooled

 

[John in CR]

I don't think anyone has taken a geared hub close to 100V with durability. You may also have issues with electrical rpm limits depending on the controller used.

 

[kdee122]

I used the MAC 12T motors on 32s A123 set up (around 109Volts). It worked fine. I did not get much time on that setup due to some issues with controllers (self inflicted not a controller problem)

 

[d8veh]

The only electronics inside are hall sensors that receive a 5v regulated supply from the controller.
Running at a high voltage won't do any harm to the gears, neither will it overheat anything. It's the current that does the damage. You have to think about the overall power going to the motor. If you double the voltage and half the current, the power's virtually the same. Doubling the voltage will double the motor's RPM, and it pushes the whole efficiency curve up the RPM band, so, when running at full throttle, but at half the no =-load RPM, the motor will be inefficient, so more heat is made. If you're struggling up a hill at 1/3 of your no-load speed, melt-down will be imminent. You have to match the motor speed to your actual travelling speed to get good efficiency,bearing in mind how much torque and power it has.

Assuming that you have a code 15 or 13 BPM, you could run at 96v and maybe 20 amps as long as you don't have many hills,or if you're careful when using the power.