The development of induction heating technology

The development trend of High frequency induction heating machine heating devices

The induction heating device consists of two parts, one is an AC power supply that provides energy, also called a variable frequency power supply, and the other is an induction coil and mechanical structure that completes the conversion of electromagnetic induction energy, called an induction furnace. Variable frequency power supply is divided into power frequency, intermediate frequency and high frequency.

 

(1) High-frequency heating equipment

It has a set of equipment that converts 50Hz AC power into high frequency (70 000～1000000Hz) electric energy, usually using electronic tube high frequency generator.

(2) Intermediate frequency heating equipment

There is also a set of equipment that converts 50Hz power frequency into intermediate frequency (500～10 000Hz) electric energy, usually intermediate frequency generator (low power factor) and thyristor inverter.

(3) Power frequency induction heating equipment

 

The power frequency of the inductor is the same as the frequency of the power grid, that is, 50 Hz, so energy can be drawn directly from the power grid. The fly in the ointment is that the power factor is too low.

 

With the development of market demand, the development of induction heating devices shows that the power supply has become high-frequency with the large-capacity of power electronic power devices, the control simulation of electronic technology devices has developed to digital, automatic control to intelligent, and the development of induction heating devices The trend presents the following characteristics:

 

(1) The power supply tends to be high-frequency and large-capacity

 

The mid-frequency band of induction heating power supply mainly uses thyristors; the super-audio frequency band mainly uses IGBT; the high-frequency band was originally SIT, and now the main development of MOSFET power supply. Power supplies using IGCT have also begun to appear. The need for high-frequency power supplies has spawned new power devices, and new devices have in turn promoted the development of high-frequency power supplies. Large-capacity induction heating power supplies, such as tens of megawatts and hundreds of megawatts, are all achievable.

 

(2) Induction heating devices tend to be mechanized and automated

 

In recent years, with the rapid development of mechatronics, computer, information and control, equipment automation, new materials, new technology, etc., the process of casting, forging and heat treatment tends to be digital and precise. Reflected in the demand for heating trends: digital manufacturing is integrated into the casting and forging process, including heating and melting equipment; casting and forging short-flow production requires reducing resource waste; large-scale casting and forging production requires industrial energy conservation; and clean production under automated control.

 

Therefore, under the characteristics of energy saving and environmental protection, induction heating equipment has a trend toward large-scale, automatic and intelligent control in response to market demand.