Single‐Phase Induction Motors

Single‐phase induction motors are used in household washers, dryers, air conditioners, and garbage disposals, where only a single‐phase source is available. The motor operates with only one of its phases connected to the single‐phase source. This chapter illustrates the steady‐state and dynamic characteristics for single‐phase applications and considers the symmetrical two‐phase induction motor. Actually the unsymmetrical two‐phase induction motor or the so‐called split‐phase induction motor is often used rather than its symmetrical two‐phase cousin. The chapter deals with unbalanced conditions in the analysis of steady‐state operation of the symmetrical two‐phase induction motor when used in single‐phase applications. The rotor windings of the two‐phase induction machine are short‐circuited. In this analysis, the rotor speed is assumed constant, whereupon, the equations which describe constant‐speed operation are linear and the principle of superposition applies. The chapter presents the free‐acceleration characteristics of the example capacitor‐start single‐phase induction motor.