What would be the continuous torque rating?
A – The motor continuous torque rating is set by heating and thus slot current; if the number of turns is increased then smaller wire would need to be used, and while the inverter would thus be capable of greater overload torque, the motor would have essentially unchanged continuous torque. Furthermore, the Chorus motor design makes better use of slot copper. In a conventional 3-phase machine, individual slots carry halves of two separate windings, often windings from different phases. The net result is that the RMS slot current is not simply the RMS winding current times the number of turns, but something less than this. A Chorus drive provides greater net slot current for the same winding current, resulting in greater MMF for the same copper losses, and thus greater efficiency. For the same RMS applied voltage, Chorus motor windings have fewer series turns for reduced copper losses. In summary, a Chorus drive offers higher efficiency, smaller size and weight, very high startup torque
