Analytical determination of steady state performance indices of single-phase induction motor, using symmetrical components of unbalanced voltages of 3-phase system

This work presents the steady-state performance indices of single phase induction motor, from symmetrical components of unbalanced three-phase system. The analysis of unsymmetrical fault conditions, using the method of symmetrical components, is a means of resolving an unbalanced three-phase system of impedances into three equivalent single-phase systems with independence impedance parameters. The implication of the above statement is that any unbalanced three-phase system of voltages or currents can be regarded as due to the super-position of two symmetrical three-phase systems having opposite phase sequence and a zero phase sequence, being equal to ordinary single-phase current or voltage system. With the knowledge of the fore-going, an equivalent circuit for a single-phase induction motor is obtained when it is considered as a three-phase induction motor with one of its stator windings disconnected. Values were assigned to the equivalent circuit parameters. Torque/slip curves of a normal single phase induction motor with slip range 0 ≤ S ≤ 2 were obtained.