trouble is I read to much
this may or may not be true , but this is what I have read
hi kv or low turn count is faster
low kv or high turn count is slower but more torque
this is the motor that you will want for a y -delta motor
lower pole count is faster
thinner laminates are quicker
other motors use 50mm 35mm and 20mm
more amp = more torque
more voltage = higher speeds
y-delta has 2 problems
if you loose 1 phase of three in delta, the wheel locks up
when you are in y the winding are in series , you have a break any where, it kills the power
delta you have 2 winding in series paralleled with the third winding, if you loose 1 winding the power can still go through the other wjnding
so if your controller screws up or you cook a winding in delta, at high speed ,watch out
but you say, I wont put enough current through my motor to cook my controller or motor to be safe
when you go delta the current increases by 1.73 so your controller and bms has to be able to handle that extra current
but you say , no problem I will increase my bms and controller to handle the extra current
so you have done all of this and are ready to try this y delta thing
so lets say that when you are in y ,your top speed is 50 kmh
you switch it to delta, your current increases by 1.73 and your speed should increase by 1.73 ,but because of wind drag you only increase by 1.5 to a speed of 75 kmh
but your controller doesn't like switching winding under full load, no problem , when you switch you now have a throttle kill that interrupts the throttle for 40 milliseconds to allow the relays to switch and then allows full power again
so you have taken care of all of this and think , what could go wrong
so now you have a controller that will handle higher current for the delta
back to my story
so you are flying down the road at 75 kmh thinking this is great
but at some point you need to slow down, so you release the throttle and you coast abit
and then ,not even thinking you switch back to y
if you do it below 50 kmh every thing is fine and you live to do it again
if you do it above 50 kmh the back emf created will fry your fets and over the handle bars you go
so now you need something to prevent it switching back to y until you reach the lower speed or
you increase the controller or fets to handle the higher voltage
so if you have a higher current and voltage controller you might as well feed it with more battery and leave it in y
correct me if im wrong
Laurence
