Induction melting furnace power type selection

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equipment electrical principle common sense

Induction melting furnace power type selection

Time: 2019-07-29

Induction melting furnace power type selection

Induction melting furnace types are mainly two types of intermediate frequency power: frequency power supply circuit and a parallel inverter having a series circuit of an inverter frequency power supply.

In China's foundry industry, the intermediate frequency induction furnace that is used to configure the thyristor (SCR) full-bridge parallel inverter intermediate frequency power supply is commonly known as induction melting furnace. The intermediate frequency induction furnace for the configuration ( SCR ) or (SCR) half-bridge series inverter intermediate frequency power supply is commonly known as the intermediate frequency induction melting furnace. Since the inverter power supplies of the two induction furnaces are different, their working performance is also very large. The difference.

SCR full-bridge parallel inverter intermediate frequency power supply medium frequency furnace ( PS series power supply), also produces SCR half-bridge series inverter intermediate frequency power supply frequency conversion furnace ( CSor CA series power supply). A brief comparison of their advantages and disadvantages and scope of application ( see Table 3) is provided below so that users can correctly select these two different types of furnaces according to their respective process requirements.

Comparison of main performance of induction melting furnace

Comparison project	SCR full bridge parallel inverterintermediate frequency power supply	SCR half bridge series inverter intermediate frequency power supply
Product specification range	160 ~ 4000 kW	50 ~ 2500 kW
Grid side power factor	Rated power is close to 1 Reduced power factor when power is reduced	Always close to 1
Harmonic interference	the same	the same
Transformation efficiency	When the same power,when power is slightly lower	When the same power, when power is slightly higher
Load adaptation range	general	broad
Constant power output capability	The output power of the cold material start-up phase is low; after the inverter control is improved, the constant power operation can be approached, but the control technology is complicated.	Constant power operation throughout the entire melting process, simple control
Operating frequency range	Up to 2500 Hz Mainly used for induction melting and insulation	Up to 100 kHz Suitable for induction melting and insulation, also for diathermy and quenching
Work stability	high. The intermediate frequency current is self-forming, and the triggering of the thyristor must have a certain current, and the anti-interference ability is strong.	Higher. The IF current must form a loop through the SCR . The SCR is a voltage control device. The external interference voltage may falsely trigger the SCR.
Device overcurrent capacity and overcurrent protection	Large overcurrent capacity and simple protection circuit	Small overcurrent capacity, complicated protection circuit and high technical requirements
Configuring the power transformer's margin requirements	Larger. The transformer configuration capacity is about 1.25 times themaximum output power of the intermediate frequency power supply.	small. The transformer configuration capacity is about 1.1 times themaximum output power of the intermediate frequency power supply .
Power sharing possibility	Can not	can
Equipment prices	Lower	The price of the CSseries is usually about30% higher than the PSseries . Recently, the CA series power supply developed by Xi'an Electromechanical Research Institute has a high performance- price ratio . The power supply capacity is below 1100 kW , and its price isslightly higher than thePS series by about 20% .
Spare part price	low	Higher