Ac Induction Motor

Global Perspectives: European efficiency labels for electric motors

New European-wide regulations took effect in June, affecting manufacturers of low-voltage (LV) induction electric motors. The Regulation (EC) N° 640/2009 states that only efficiency Class IE2 or IE3 motors can be placed on the market in the European Economic Area after June 16, 2011.

As of this writing, a number of interpretation issues were subject of intense debate within the UK and Europe. REMA (Rotating Electrical Machines Association), the UK trade association for motor manufacturers, is updating developments through a related organization, BEAMA, the Federation of British Electrotechnical and Allied Manufacturers’ Associations.

The legislation is applicable for 2, 4, and 6-pole 50Hz and 60Hz motors in the power range between 0.75 and 375kW. The International Efficiency (IE) rating defines how efficiently the motor operates, replacing the previously used EFF 1 and EFF2 designations. (See link to law, below.)

The measuring method for the IE rating is an important differentiating criterion from what has been used in the past, Siemens Drives Technologies Division told CEE. Previously, the stray load losses were taken into account with a fixed 0.5%; these are now precisely calculated. Siemens has used examples of its own motors to indicate what this will mean in practice: A 4-pole 5.5 kW motor for 50 Hz, which previously had an efficiency of 89.2%, now has an efficiency of 88.2% according to the new efficiency calculation method in compliance with IEC 60034-2-1:2007. For the 60Hz type, the efficiency is 89.5%. This change in the efficiency—with the motor technology remaining the same—will be applicable for all motor manufacturers as a result of the modified measuring method.

Making comparisons easy

For plant and machinery builders, this offers the advantage that motors can now be more easily compared with one another. The somewhat higher purchase price for state-of-art technology should have a relatively fast payback time in operation. As a consequence, drive solutions involving a changeover to IE2 motors frequently have a payback time of less than two years, says Siemens.

Dr. Jürgen Brandes, CEO Business Unit Large Drives of Siemens AG, explains what increased efficiency and energy savings can offer in reality. He said, “The cost of an electric motor in operation represents 90% of the overall costs, so it makes perfect sense to further increase the efficiency of these products. Experts have estimated that, worldwide, 120 Terawatt hours of energy could be saved annually by using variable-speed drives and high-efficiency motors.

Nikola Tesla, genius inventor who changed world. AC, radio ...

His real name was Nicolae Tesla, born on July 9 1856 in the village of Smiljan, Croatia.

Tesla moved to the United States in 1884, arriving in New York City with four cents in his pocket where he found employment with Thomas Edison who quickly became a rival

George Westinghouse purchased the patents to his induction motor, and made it the basis of the Westinghouse power system which still underlies the modern electrical power industry today

He also did notable research on high-voltage electricity and wireless communication; at one point creating an earthquake which shook the ground for several miles around his New York laboratory.

Among other he devised a system which anticipated world-wide wireless communications, fax machines, radar, radio-guided missiles and aircraft.

Nikola Tesla developed polyphase alternating current system of generators, motors and transformers and held 40 basic U.S. patents on the system, which George Westinghouse bought, determined to supply America with the Tesla system.

Tesla coil is one of Nikola Tesla’s most famous inventions. It is essentially a high-frequency air-core transformer

As early as 1892, Nikola Tesla created a basic design for radio. On November 8, 1898 he patented a radio controlled robot-boat.

Most of us, think of Guglielmo Marconi as the father of radio, and Tesla is unknown for his work in radio.

Marconi claimed all the first patents for radio, something originally developed by Tesla. Nikola Tesla tried to prove that he was the creator of radio but it wasn’t until 1943, where Marconi’s patents were deemed invalid;

After the AC induction motor, we think that the greatest invention of Tesla was the electric car. This was no ordinary battery driven car because this car took its power from the ether

Tesla had also installed one of his powerful oscillators somewhere near Niagara Falls to provide the wireless energy needed to power the vehicle

This vehicle, powered by an AC motor, was driven to speeds of 90 m.p.h. and performed better than any internal combustion engine of its day!

Tesla’s wireless transmission of electricity ******************

The secondary coil was GROUNDED to the earth, producing waves which traveled to the opposite side of the world.

The returning waves were discharged through the atmosphere.

When Tesla had demonstrated the feasibility of his wireless power system, he rushed back to New York to begin construction on a transmitter located at Wardenclyffe, Long Island, New York. Morgan stonewalled him and created a panic on Wall St. in 1907. Millionaire John Jacob Astor, Tesla’s close friend and financier, died on the Titanic in 1912.

AC Induction motor control

AC motors for high-performance applications, analysis and control

A Textbook of Design of Electrical Installations

Artificial Intelligence: Methodology, Systems, and Applications, 14th International Conference, AIMSA 2010, Varna, Bulgaria, September 8-10, 2010. Proceedings

The field orientation principle in control of induction motors