PRELIMINARY STUDY OF THE REQUIREMENTS FOR VARIABLE SPEED ELECTRIC DRIVES

The preliminary study of a variable speed electric drive requires knowledge of a number of basic data, such as required power, supply voltage, the type of operation (number of quadrants), speed range, and the accuracy over speed. We also show some effects on motors of the supply through a converter: the voltage peaks, the effects of voltage gradients, and the losses caused by harmonics. Nowadays, this know-how is very important for the design of a circuit where electric engine is being used. And the number of applications of electric drives seems that it does not have end: industrial processes such as pumps and compressors, machinery like presses and grinders, industrial cold and heat conditioning, steel and paper industry, etc.