Type a branch, a subject or a topic — “round robin”, “paging”, “civil”.

Electrical Machines

Transformers, DC machines and induction motors look like three subjects and are one: a changing flux linking a coil. These topics animate the flux and the force rather than starting from the equivalent circuit.

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1 topic you can watch now, 23 still to come.

Electromechanical energy conversion

The one principle the whole subject is an application of.

  • Magnetic circuits and reluctance
  • Faraday's and Lenz's laws
  • Force and torque from a field
  • Hysteresis and eddy current losses

Transformers

A machine with no moving parts, and the easiest one to reason about.

  • Ideal transformer and turns ratio
  • Equivalent circuit and referred quantities
  • Open-circuit and short-circuit tests
  • Regulation and efficiency
  • Autotransformers and three-phase connections

DC machines

Commutation: mechanically switching the current to keep torque up.

  • Construction and armature windings
  • EMF and torque equations
  • Shunt, series and compound characteristics
  • Starting and speed control
  • Armature reaction and commutation

Induction machines

The workhorse: no brushes, no supply to the rotor at all.

  • Rotating magnetic field
  • Slip and rotor frequency
  • Torque-slip characteristic
  • Starting methods
  • Speed control and single-phase motors

Synchronous machines

The machine that generates almost all the world's electricity.

  • Alternator construction and EMF equation
  • Voltage regulation methods
  • Parallel operation and synchronisation
  • Synchronous motor and V-curves
Dashed entries are mapped but not animated yet. The running order is not fixed until a topic is built. Browse the other subjects.