Unformatted text preview: to get the same torque as we had in the original design. (In other words, if the dc voltage was dc V before, and ignoring semiconductor drops, will we need dc V 2 , 2 / dc V or something else ?) Problem 27 – Problem 3.10-3 from Electromechanical Motion Devices Problem 28 – Problem 3.10-6 from Electromechanical Motion Devices Problem 29 – PM DC Machine Performance A PM DC machine has a back emf constant of 0.1 Vs, and an armature resistance of 300 m Ω . The armature voltage is 25 V, and the load torque may be expressed 3 400 2 ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ = r l T ω Find the rotor speed, the armature current, and the efficiency....
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- Spring '08
- Electric motor, Electromechanical Motion Devices, pm dc machine, VR Stepper Design