
Doctorbass wrote:
btw, i'm correcting all my previously understanding of Phase current and current multiplication. LFP and Justin are now convincing me to correctly better play with the dark side of electrons and copper!
Doc


liveforphysics wrote:Doctorbass wrote:
btw, i'm correcting all my previously understanding of Phase current and current multiplication. LFP and Justin are now convincing me to correctly better play with the dark side of electrons and copper!
Doc
This is outstanding news Doc!You're going to have the insight now to make better choices and matching up battery with motor with controller than ever before now, and the results are going to kick ass harder than ever before!

Doctorbass wrote:I remember that the controller used with my 5302 at 172A burst become VERY HOT!! and that the same conditions with my 5305 , make the controller still cold or a bit warm...
Doc

liveforphysics wrote:Doctorbass wrote:I remember that the controller used with my 5302 at 172A burst become VERY HOT!! and that the same conditions with my 5305 , make the controller still cold or a bit warm...
Doc
I bet! That controller running the 5302 was pumping out 2.5times the current the 5305 controller would be doing when starting from a stop if they are both drawing in 172amps at the battery! Easily could have been in the >600phase-amp range starting from a stop.
Like I said, the series-parallel switching plan you've got has the ability to take away half or more than half the heat load on the motor for the first 0-20mph of acceleration or so, that could be pretty handy.But then the question becomes, is it easier to mechanically switch motor windings with relays inside the motor, or just make a controller FET stage capable of more currents (like maybe using some TO-264 package FETs on a custom heatsink).

andreym wrote:liveforphysics wrote:Doctorbass wrote:I remember that the controller used with my 5302 at 172A burst become VERY HOT!! and that the same conditions with my 5305 , make the controller still cold or a bit warm...
Doc
I bet! That controller running the 5302 was pumping out 2.5times the current the 5305 controller would be doing when starting from a stop if they are both drawing in 172amps at the battery! Easily could have been in the >600phase-amp range starting from a stop.
Like I said, the series-parallel switching plan you've got has the ability to take away half or more than half the heat load on the motor for the first 0-20mph of acceleration or so, that could be pretty handy.But then the question becomes, is it easier to mechanically switch motor windings with relays inside the motor, or just make a controller FET stage capable of more currents (like maybe using some TO-264 package FETs on a custom heatsink).
In that case i believe the controller should be INSIDE the motor because just imagine the wires thickness to allow say 500-1000amps through phase wires? 1awg? 0awg?
and with controller located inside (at least power fets) you could easily power this with say 20kw at 100v and 200amps using 10-8awg)

liveforphysics wrote:Doctorbass wrote:I remember that the controller used with my 5302 at 172A burst become VERY HOT!! and that the same conditions with my 5305 , make the controller still cold or a bit warm...
Doc
I bet! That controller running the 5302 was pumping out 2.5times the current the 5305 controller would be doing when starting from a stop if they are both drawing in 172amps at the battery! Easily could have been in the >600phase-amp range starting from a stop.
Like I said, the series-parallel switching plan you've got has the ability to take away half or more than half the heat load on the motor for the first 0-20mph of acceleration or so, that could be pretty handy.But then the question becomes, is it easier to mechanically switch motor windings with relays inside the motor, or just make a controller FET stage capable of more currents (like maybe using some TO-264 package FETs on a custom heatsink).

Doctorbass wrote:That 5302 is also a PURE current monster eater!
Doc

John in CR wrote:Doctorbass wrote:That 5302 is also a PURE current monster eater!
Doc
The 5302 is a much better motor as far as I'm concerned. Look, it out performed the other one despite being handicapped by a lower current limit. Imagine what it would have done with a controller manly enough to feed it the current it wanted. The results wouldn't have been even close. It wanted and could handle double the current, but it got less current. As long as you're not bumping up against saturation limits of the stator it's capable of 0-70 in under 3 seconds with double the current.
John

steveo wrote:John in CR wrote:Doctorbass wrote:That 5302 is also a PURE current monster eater!
Doc
The 5302 is a much better motor as far as I'm concerned. Look, it out performed the other one despite being handicapped by a lower current limit. Imagine what it would have done with a controller manly enough to feed it the current it wanted. The results wouldn't have been even close. It wanted and could handle double the current, but it got less current. As long as you're not bumping up against saturation limits of the stator it's capable of 0-70 in under 3 seconds with double the current.
John
5303 all the way!!!... Dual winding x5306-x5303 ... hard to beat!




fechter wrote:The resistance losses (and therefore heating) are a function of current squared, so a 5302 is going to result in more heating for a given amount of torque, but will have a higher no-load speed.

Users browsing this forum: No registered users and 4 guests