(1) All coils have the same pitch, so they are wound and discharged;

(2) the end of the coil has little deformation and is easy to shape;

③ The number of coils is twice that of single-layer windings, so the labor intensity of wire embedding is high;

(4) The edges of out-of-phase coils are embedded in the same slot, which is prone to short-circuit fault;

⑤ Insulation should be added between layers, which will reduce the tank full rate.