No-Load Speed Characteristics of the 2-Phase Servomotor

The no-load speed as a function of coil insertion slot opening and rotor skew is analyzed by operating directly on the flux density function of the stator for the 1-coil-per-pole motor. In addition, the no-load speed dependence on nonsinusoidal current excitation is derived. An attempt is made to note the effect of a skewed rotor which has been smeared by a manufacturing process. The maximum electrical no-load speed is 0.9986 of synchronous speed, for a total skew of about 119 electrical degrees with a stator coil slot opening of about 20 electrical degrees.