Introduction
Npaq MR Hardware Manual
1.1.1. 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 switching amplifier types:
An EfficiencyFactor of approximately 90% should be used in the following equations.
Brushless Motor
Output Power
Rotary Motors
Pout [W] = Torque [N·m] * Angular velocity[rad/sec]
Linear Motors
Pout [W] = Force [N] * Linear velocity[m/sec]
Rotary or Linear Motors
Pout [W] = Bemf [V] * I(rms) * 3
Ploss = 3 * I(rms)^2 * R(line-line)/2
Pin = SUM ( Pout + Ploss ) / EfficiencyFactor
DC Brush Motor
Pout [W] = Torque [N·m] * Angular velocity[rad/sec]
Ploss = I(rms)^2 * R
Pin = SUM ( Pout + Ploss ) / EfficiencyFactor
For linear amplifier types:
An EfficiencyFactor of approximately 50% should be used in the following equations.
Linear Motor
Pdiss[W] = MotorCurrentPeak[A] * TotalBusVoltage[V] * 3 / 2
Pin = SUM ( Pdiss ) / EfficiencyFactor
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