Describing an apparatus nearly identical to Baily’s, French electrical engineer Marcel Deprez published a paper in 1880 that identified the rotating magnetic field principle and that of a two-phase AC system of currents to produce it.
In 1887, American inventor Charles Schenk Bradley was the first to patent a two-phase AC power transmission with four wires.
When an AC motor is in steady-state rotation (motion), the magnetic fields of the rotor and stator rotate (move) with little or no slippage (near synchrony).
The magnetic forces (repulsive and attractive) between the rotor and stator poles create average torque, capable of driving a load at rated speed.
With no load, the speed will be very close to synchronous.An AC motor is an electric motor driven by an alternating current (AC).The AC motor commonly consists of two basic parts, an outside stationary stator having coils supplied with alternating current to produce a rotating magnetic field, and an inside rotor attached to the output shaft producing a second rotating magnetic field.This kind of rotor is the basic hardware for induction regulators, which is an exception of the use of rotating magnetic field as pure electrical (not electromechanical) application.Most common AC motors use the squirrel-cage rotor, which will be found in virtually all domestic and light industrial alternating current motors.
Principle of operation of single phase capacitor start induction motor
It is typically cast aluminum or copper poured between the iron laminates of the rotor, and usually only the end rings will be visible.The vast majority of the rotor currents will flow through the bars rather than the higher-resistance and usually varnished laminates.Other types of motors include eddy current motors, and also AC/DC mechanically commutated machines in which speed is dependent on voltage and winding connection.Alternating current technology was rooted in Michael Faraday’s and Joseph Henry’s 1830-31 discovery that a changing magnetic field can induce an electric current in a circuit.For this reason, ordinary squirrel-cage motors run at some tens of RPM slower than synchronous speed.