Abstract: The bundle of laminations in an electric generator as motor contains a plurality of lamination stacks arranged in series in an axial direction and a plurality of slots in which are arranged the conductors of the machine winding. In order to improve the dissipation of the heat losses from the bundle of laminations and the winding, laminations are contained in the stacks which have a slot width greater than the width of the conductors and which have on the slot floor a recess of a greater depth. Thus side ducts are formed alongside the conductor which are in connection with the air gap of the machine, and axial cooling channels are formed on the slot floor which open at least on one side into a radial cooling channel. By reversible packing of these laminations, the position of the lateral channels can be altered.

Abstract: In a transposed bar, the partial conductors of which traverse different height levels and are twisted by offsetting from one layer to the next, the partial conductors are disposed next to each other in four layers, and the twisting is carried out so that always two adjacent partial conductors are jointly offset.

Abstract: A pole coil wherein improved heat transfer at cooling fins thereof is achieved and includes cooling fins which are subdivided in the longitudinal direction into short portions which are bent out so that they are disaligned with each other. The pole coil is suitable for electrical machines and apparatus and especially for the revolving excitation windings of synchronous electric machines.

Abstract: The method includes maintaining the coolant circulation in a fluid-cooled hydropower generator also when the hydropower generator is shut down, and interrupting only the coolant circulation of the heat exchangers when the generator is in the shutdown condition. The leakage and conductivity control means of the circulation system are in constant operation.