Transient analysis of a split phase induction motor used in a reciprocating compressor

The transient speed build-up of a split-phase induction motor with a compressor load was studied. Equivalent circuits for the motor with and without the auxiliary starting winding were derived by using symmetrical components and Gabriel Kron's generalized machine theory. The resulting dynamical equations were expressed in state-variable notation to facilitate their solution by a digital computer. The compressor load was analyzed from fundamental thermodynamic principles, and a curve of torque versus angular position was derived. Computer programs for calculating transient speed and currents during acceleration from standstill to final speed were written and applied to a typical refrigerator motor-compressor unit. The results compared favorably with experimental observations.