Beginning in the late 1950s, an important technological change took place in the field of electric drive -- speed control was implemented on AC motors, which were originally used only for constant speed drive, to replace DC motors, which were complicated to manufacture, expensive and difficult to maintain. In recent ten years, with the penetration of power electronics technology, microelectronics technology and modern control theory into the field of AC electric drive, frequency converter has been widely used in the speed control of AC motor. Its main characteristics are high efficiency driving performance and good control characteristics.  In the fan, water pump, compressor and other fluid machinery application can save a lot of electric energy;  In textile, chemical fiber, plastic, chemical and other industrial fields, the use of inverter automatic control performance can improve the quality and quantity of products; In the machinery industry, the application of frequency converter is an important means to transform the traditional industry and realize electromechanical integration. Ac servo system is replacing DC servo system in factory automation technology. From hundreds of watts of servo system to tens of thousands of kilowatts of extra-large power high-speed transmission system, from the general requirements of a small range of speed transmission to high precision, fast response, a large range of speed transmission, from single transmission to multi-machine coordination, can use AC speed regulation device. It can almost be said that where there is an electric motor, there is the use of frequency converters.

Frequency converters are a latecomer to the Chinese market, but they are growing fastest. Frequency converters are mainly divided into general type, engineering type and special type. The reasons for the rapid growth of universal frequency converters are mainly as follows: 

 

Constantly introduce new products to meet the specific requirements of different users. Products are generally updated within 5 years. Its products can meet the special requirements of different users. 

 

Powerful communication function and comprehensive supporting software are a major feature of automation products. This in our country papermaking, chemical industry, steel, machinery manufacturing and many other industries from the technical transformation to the automatic control of the full rapid development process, especially to show its competitive advantage. 

 

Because of its low price, the frequency converter has to choose some original devices at the bottom of the manufacturing, or the amount of wealth is too small when selecting the original device. For example: voltage resistance, temperature resistance, voltage, current impact and so on. Therefore, there are relatively more problems in the practice of use in our country, which is what we feel very sorry for.