System Power Requirements
The following equations can be used to determine total system power requirements. The actual power required from the mains supply will be the combination of actual motor power (work), motor resistance losses, and efficiency losses in the power electronics or power transformer. For 3-phase brushless motors:
Use an EfficiencyFactor of approximately 90% in the following equations.
| PWM Amplifier Types | ||
| Power Output [W] | = Torque [N·m]· Angular Velocity [rad/sec] | ;Rotary |
| = Force [N]· Linear Velocity [m/sec] | ;Linear | |
| = Bemf [Vrms l-n] · MotorCurrent [Arms] · 3 | ;Rotary or Linear | |
| Power Loss [W] | = MotorCurrent2 [Arms2] · MotorHotResistance [Ω l-l] · 3/2 | |
| Power Input [W] | = (Power Output [W] + Power Loss [W]) / EfficiencyFactor | |
| NOTES | |
| l-n = | line to neutral |
| l-l = | line to line |
| Vrms = | Volt rms |
| Arms = | Ampere rms |
| Apk = | Ampere peak |
| Vdc = | Volt DC |