Since 1833, one of the problems encountered in electric motors was the performance he had in relation to the transformation of electrical energy into mechanical. Great strides have been made to achieve this goal, where a machine does this transformation, with less waste of electricity. Research has advanced in this direction and focused on improving the conductive, magnetic and insulation materials used in the engines.
The use of permanent magnets is an old idea and researchers are returning to it, because now they are more affordable and more powerful, this construction has been quite attractive.
The use of the magnets inside the rotor, without the existence of the aluminum or copper cage causes the induction of the current does not occur, and also does not occur the electromagnetic flow through the rotor, obtaining therefore a motor heating much inferior if compared to other . Thus, we obtain yields between 95% and 97% varying according to the carcass, indicating that the losses in this type of motor do not exceed 5% of the total energy absorbed from the grid, thus saving energy. acme electrical transformers