Week 09
Induction Machines
I revisit magnetic circuits, transformers, and rotating machines around my transformer report and calculation sheets.
What I connect in this unit
An induction machine needs slip because induced voltage and torque vanish if the rotor reaches synchronous speed. Slip sets rotor frequency and effective rotor impedance, shaping the torque-speed curve; at standstill, slip equals one and starting current is large.
Concept map
- Slip
- Rotor frequency
- Torque-speed curves
- Starting current
Technical anchor
The defining relations are s = (n_s - n_r)/n_s and f_r = s f_s; normal motoring lies in 0 < s < 1.
How I review it
Mark starting, near-rated, and breakdown-torque points on the curve, then check whether slip, rotor frequency, and current trends agree with the equivalent circuit at each point.
Connection to the full course
Unit 9 of 12. Unit numbers expand the saved report and calculations into a reading sequence rather than an attendance record.