Series three-phase asynchronous motor has a simple structure, easy to manufacture, use and maintenance, reliable operation and low mass, low cost. Induction motor has a higher operating efficiency and better operating characteristics, near constant speed from no load to full load within the range of most industrial and agricultural production to meet the requirements of mechanical transmission. Induction motors are easy to generate a variety of school types of protection, in order to adapt to different environmental conditions. Asynchronous motor is running, you must annually sliding scale demand from mechanical and electrical hardware tools, hardware, improve product quality, increase capital expansion, cooperation between enterprises and other trends in increased strength characteristics for large hardware companies, it is a good thing, when such a large enterprises to adapt to this trend, only gradually expand. For in the hardware business, it may exist on product quality gap, relatively fewer opportunities for cooperation, let alone the capital. Therefore, the continuous development and progress in the hardware industry among small business environment will be increasingly difficult to survive. Matthew, referring to the strong stronger and the weak weaker phenomenon. For the hardware industry, the strength of enterprises to take advantage of hardware trend toward better analyze the development of enterprises, and for SMEs, only tenacious upgrade to spell a world power draw reactive excitation power in the hardware industry, to make the grid power factor worse.