Starting losses in windings of double squirrel-cage motors

Abstract

The losses in the windings of a double squirrel-cage motor during starting, braking and reversing, differ in many respects from those in an ordinary squirrel-cage motor. Although the total rotor loss in both cases is the same, yet the distribution between the two cages of the double-cage motor is very unequal. The outer cage, in which the dimensions of the conductors are as a rule smaller, will take the greater part of the loss and will therefore be rather heavily loaded. The loss which will be produced in the stator winding in a double-cage motor is smaller than the corresponding loss in an ordinary squirrel-cage stator. Further, there is not a simple relationship between starting, braking and reversing losses.