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The paper considers the latest trends in design of electric machines and drives from the aspects of power efficiency and the increasing cost of electric energy. The most important issue thereby is the amount by which the power losses can be reduced, i.e. the efficiency of the motor can be increased, when new materials and advanced knowledge, construction and technology are utilized. The special interest is paid to industrial induction motors since they consume most of the generated electric energy and are widely used in electric drives with or without speed control. Two examples of induction motors have been considered. The ratings of the first motor are 22 kW, 400 V, which is a typical low power motor for wide applications. The ratings of the second motor are 2500 kW, 6000 V, which is a high power motor manufactured and utilized piecemeal. The possibility of reducing the power losses in the motor by means of design, i.e. by increasing the volume of its active parts, and the influence of the increased volume on the price of the motor and the reduction of pollution of the environment have been analyzed in detail.

In the paper an overview of achievements known in the world in the area of construction and application of various electric generator systems for wind turbines is given. Using the available literature and other technical data a comparison is made between the following commonly used types of generator: induction, synchronous with classical excitation, synchronous permanent-magnet and doubly-fed induction generator. A basic concept and some selected details from the design and construction of the first wind generator developed and built in Croatia are given. The generator is three-phase, low speed, 60 poles, designated for direct-drive, power rating 1000 kVA. At rotating speeds between 10 rpm and 30 rpm, the generator voltage and frequency change in the range of 250-690 V and 5-14, 5 Hz. Based on experience acquired by carrying out the first project involving construction of the wind turbine and generator system, the other types of generator are also considered and the optimal solutions are sought for future constructions. Some theoretical and practical significance is given to the possibility and justification for construction of a direct-drive permanent magnet generator, which is estimated to be the most promising technical solution.