**9. Conclusion**

Nowadays the development of windmill industry is holding back by one serious problem. It is very difficult to transform with high efficiency the nonstandard energy to the standard energy. The using of the induction alternators or the synchronous alternators cannot solve this problem with good results. As a rule in this case we have low efficiency, complex design and high total cost. The problem is becoming more difficult when you make attempt to build the row of windmills from small power to big power (10 kW–1 MW). The concept of the DFIA proves to be very effective for solving windmills problems. It is possible to transform the nonstandard energy in to the standard energy with high efficiency. Windmills may operate as stand-alone or grid tied. It is possible to build the row of windmills with the same design. But the main reason of the application the DFIA is the low total cost of windmill and electronic control system. The new design of this concept is

*Application of an Asynchronous Synchronous Alternator for Wind Power Plant of Low, Medium… DOI: http://dx.doi.org/10.5772/intechopen.89255*

presented. The concept is confirmed by the complex engineering calculations and the manufacturing of the prototypes.

This concept can be used for design of windmill row with output power up to 1 MW.
