  The possibility of a substantial reduction of weight and size of electrical
generators is the main incentive behind the effort to develop superconducting
armature windings based on coated conductors in the form of wide tapes with
large aspect ratio. The main obstacle to the application of coated
superconductors in stator windings is the large losses incurred due to the ac
magnetic field produced by the rotor's dc coils of the field windings. In the
range of frequencies typical for aircraft generators, the hysteretic losses in
wide tapes are unacceptably high. They can be reduced by dividing the
superconducting layer into multiple filaments separated by non-superconducting
barriers. However, the lack of current sharing between the filaments makes the
conductor vulnerable to the localized defects, so that a single blockage can
impede the flow of transport current through the whole length of a given
filament. We present estimates of reliability as well as the magnetization
losses in multiply connected superconductors. In this type of superconducting
tape, a sparse network of superconducting bridges, which allows for current
sharing, connects the filaments. The trade-off between the different types of
losses and the connectivity requirement imposes restrictions on the number of
filaments and properties of the network of bridges.
