B
BobG
- Jan 1, 1970
- 0
Anyone know of a site that describes DC motor tradeoffs? I know torque
is proportional to current and turns, and there are practical problems
with wire size and resistance that limit number of turns, etc. Lets say
I have a 3 pole armature and a 7 pole armature wound with the same
number of turns and wire size. Will they have the same torque? Which
one will have greater rpm? I know the inductance goes up with turns.
Seems like there should be a rule about L/R time constant and RPM
somewhere in the rule of thumb list. Some big hefty motors cant be PWMd
faster than a kilohertz or so... is this because of large L?
is proportional to current and turns, and there are practical problems
with wire size and resistance that limit number of turns, etc. Lets say
I have a 3 pole armature and a 7 pole armature wound with the same
number of turns and wire size. Will they have the same torque? Which
one will have greater rpm? I know the inductance goes up with turns.
Seems like there should be a rule about L/R time constant and RPM
somewhere in the rule of thumb list. Some big hefty motors cant be PWMd
faster than a kilohertz or so... is this because of large L?
