| Popis: |
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. |
