Motor is recognized as power-hungry, which accounts for more than 60 percent of the national economy with electricity, its energy saving, has great potential. To build a conservation-oriented society, we must do the work content. Promote frequency control technology is a necessary means to achieve this goal, it is the alternating-current motor energy-saving priorities.
With the rapid development of modern power electronics technology and computer control technology, promoting technological revolution electrical drive. AC DC speed governor substituted, replace the analog control computer numerical control has become a trend. AC Motor today to save energy, improve production processes, improve product quality, as well as a major means of improving the operating environment. Frequency of its high efficiency, high power factor, and excellent speed and start braking performance and many other advantages at home and abroad have been recognized as the most promising way of speed.
Previous high-voltage inverter, thyristor rectifier, inverter and other devices SCR structure, a lot of shortcomings, harmonic large, on the grid and the motor has an impact. In recent years, developed a number of new devices will change the status quo, such as IGBT, IGCT, SGCT like. They constitute the high-voltage inverter, high performance, can achieve PWM inverter, even PWM Rectifier. Not only has the small harmonics, power factor is also greatly improved.