This chapter provides a very basic overview of the operational principles of electric motors.

The operation of any electric motor (machine) is based on the phenomenon of electromagnetic induction – the interaction of a conductor with an electric current and magnetic field. There are three fundamental concepts of implementation of an electric motor:

A permanent magnet (or electromagnet) motor

The current in the conductor influences the flux induced by a permanent magnet (or electromagnet) or opposite transformation.

In the figure:

	I – The direction of the flowing current;
	B – Direction of magnetic flux created by the permanent magnets
	F – Force and its direction created by current and magnetic flux
	In green – rotating contact surface enabling to change direction of current while motor is rotating.
	In orange – conductor (a copper wire)

The created force creates a momentum on the conductor i.e. it starts to rotate. During rotation the conductor changes the connection to the contact surfaces, thus changing the current direction in the conductor. The created momentum keeps turning the conductor and motor keeps running.