motor speed formula
- Thread starter 944
- Start date
Have you checked the wiki?
(see link in my signature)
There should also be some information in the sticky threads in this subforum.
(see link in my signature)
There should also be some information in the sticky threads in this subforum.
Kingfish
100 MW
Desired: Top speed of motor
Given: Voltage, RPM, Gear Ratio, and Wheel Size.
First, this question is a little generalized because we don’t know the amount of work i.e. Power. Without that – there is no way to determine the second part of the equation which requires Force, and/or Efficiency.
The best that we can do is to evaluate the motor velocity constant Kv
Kv = RPM/V
However, RPM on a loaded motor is dependent upon Wheel Diameter & Gearing. We are not given the Load or the Velocity; from Load we can determine Power, and from Velocity – the RPM at 1:1 Gearing.
So to really answer your question, I look for Voltage, Wattage, Efficiency, RPM, and Operational Temperature limits… and physical dimensions are important too, such as L x W x H & Mass. The values of these properties are commonly posted on Manufacturers datasheets. Once we have these values, then we can calculate both the unloaded motor speed and loaded, both of which are important in application design.
From Power (Wattage) and Voltage, we can determine Amperage, and from Efficiency – the amount of Heat generated. High-efficiency motors are prized in that it’s possible to use air-cooling. Conversely lower-efficient motors will require more effort to control thermo-loading, and thus affect the operational range which in turn affects the scope of Velocity, or Speed as you call it.
But for myself, I can’t calculate your request given just Voltage and RPM. At the minimum we still need Power for any theoretical discussion to continue.
Onward through the fog, KF
Given: Voltage, RPM, Gear Ratio, and Wheel Size.
First, this question is a little generalized because we don’t know the amount of work i.e. Power. Without that – there is no way to determine the second part of the equation which requires Force, and/or Efficiency.
The best that we can do is to evaluate the motor velocity constant Kv
Kv = RPM/V
However, RPM on a loaded motor is dependent upon Wheel Diameter & Gearing. We are not given the Load or the Velocity; from Load we can determine Power, and from Velocity – the RPM at 1:1 Gearing.
So to really answer your question, I look for Voltage, Wattage, Efficiency, RPM, and Operational Temperature limits… and physical dimensions are important too, such as L x W x H & Mass. The values of these properties are commonly posted on Manufacturers datasheets. Once we have these values, then we can calculate both the unloaded motor speed and loaded, both of which are important in application design.
From Power (Wattage) and Voltage, we can determine Amperage, and from Efficiency – the amount of Heat generated. High-efficiency motors are prized in that it’s possible to use air-cooling. Conversely lower-efficient motors will require more effort to control thermo-loading, and thus affect the operational range which in turn affects the scope of Velocity, or Speed as you call it.
But for myself, I can’t calculate your request given just Voltage and RPM. At the minimum we still need Power for any theoretical discussion to continue.
Onward through the fog, KF
Kingfish
100 MW
I thought of another idea:
If you knew the Mass of the Wheel and the Wheels' RPM, and you had the Voltage of the motor and it's shaft diameter, then you could figure out Power.
Have you seen this Power Calculator? 8)
Under-worked, KF
If you knew the Mass of the Wheel and the Wheels' RPM, and you had the Voltage of the motor and it's shaft diameter, then you could figure out Power.
Have you seen this Power Calculator? 8)
Under-worked, KF
