Brushless DC Motor's Peak Torque

R

Thread Starter

Ron Mao

Does the below BLDC motor have the Peak Torque (20oz-in) at the rated speed?

Rated_Voltage: 24V
Rated_Speed: 4000RPM
Back_EMF_Constant: 3.7Vp/KRPM
Peak_Current: 4.4A
Rated_Current: 2.2A
Peak_Torque: 20oz-in
Rated_Torque: 10oz-in
Resistance: 1.5Ohms
Inductance: 2mH

Here is my calculation:

x = Rated_Speed * Back_EMF_Constant + Peak_Current * Resistance

If the above "x" exceeds Rated Voltage, then the motor can not exert Peak Torque(20oz-in) at the rated speed.

For the above motor:
21.4V = 4000RPM * 3.7Vp/KRPM + 4.4A * 1.5Ohms

Because 21.4v is less than Rated Voltage(24v), so it can exert the Peak Torque(short time) at the rated speed.

Is my calculation correct?

Thank you.
 
Yes.
Your approach and calculations are ok.
Nanda

>x = Rated_Speed * Back_EMF_Constant + Peak_Current *
>Resistance
>
>If the above "x" exceeds Rated Voltage, then the motor can
>not exert Peak Torque(20oz-in) at the rated speed.
>
>21.4V = 4000RPM * 3.7Vp/KRPM + 4.4A * 1.5Ohms
>
>Because 21.4v is less than Rated Voltage(24v), so it can
>exert the Peak Torque(short time) at the rated speed.
>
>Is my calculation correct?
 
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