Synchronous Motors

INDUCTION MOTOR CONSTRUCTION

Figure 6.1 illustrates a typical two-pole stator for an induction motor. The two main types of rotors are squirrel-cage and wound rotors. Figures 6.2 and 6.3 illustrate squirrel-cage induction motor rotors.

Figure 6.1: The stator of a typical induction motor, showing the stator windings. ( Courtesy of MagneTek, Inc.)

Figure 6.2: ( a) Sketch of squirrel-cage rotor. ( b) A typical squirrel-cage rotor. ( Courtesy of General Electric Company.)

Figure 6.3: ( a) Cutaway diagram of a typical small squirrel-cage induction motor. ( Courtesy of MagneTek, Inc.) ( b) Cutaway diagram of a typical large squirrel-cage induction motor. ( Courtesy of General Electric Company.)

The rotor consists of a series of conducting bars installed into slots carved in the face in the rotor. These bars are shorted at both ends by shorting rings. This design is known as a squirrel-cage rotor. The second type is known as a wound rotor. A wound rotor (Figs. 6.4 and 6.5) has three phase windings that are...