Common sense of induction heating furnace

1. The power supply of the induction heating furnace is three-phase alternating current, the frequency is 50Hz, and the incoming line voltage is 380V. For high-power induction heating furnaces, the input voltage can also be 660V, 750V, 950V, etc.

2. The induction heating furnace is powered by a transformer, which can be divided into two types: dry-type transformers and oil-cooled transformers according to different cooling media. In the induction heating furnace industry, we recommend oil-cooled rectifier transformers.

3. Under the rated voltage or rated load, the output power of the induction heating furnace can be adjusted smoothly and continuously, and the adjustment range is 5%-100% of the rated power;

4. The frequency conversion power supply cabinet of the induction heating furnace is the core component, which is composed of two parts: rectifier/inverter. The function of the rectifier part is the process of converting the 50HZ alternating current into a pulsating direct current. According to the number of rectification pulses, it can be divided into 6-pulse rectification, 12-pulse rectification, and 24-pulse rectification. After rectification, a smoothing reactor will be connected in series with the positive pole. The function of the inverter part is to convert the direct current generated by rectification into an intermediate frequency alternating current and then supply power to the induction coil.

5. When the output voltage of the induction heating furnace exceeds 1.1-1.2 times of the maximum output voltage or exceeds the voltage setting value, the overvoltage protection system will act to make the device automatically stop working and issue an alarm signal – light up the overvoltage indicator light of the instrument box .

6. The capacitor cabinet of the induction heating furnace is a device that provides reactive power compensation to the induction coil. It can be simply understood that the amount of capacitance directly affects the power of the equipment. The parallel resonance induction heating furnace has only one kind of resonance capacitor (electric heating capacitor), while the series resonance induction heating furnace has filter capacitors in addition to the resonance capacitor (electric heating capacitor).

7. When the inverter bridge of the induction heating furnace is directly connected and short-circuited, the protection system will act immediately to stop the device automatically, and send out an overcurrent indication signal – light up the overcurrent indicator light of the instrument box.

8. When the working pressure of the water cooling system of the induction heating furnace is lower than a certain value, the induction heating equipment, quenching heat treatment equipment, and quenching and tempering heat treatment production line can automatically stop and light up the water pressure indicator on the panel.

9. The frequency conversion device of the induction heating furnace adopts thyristor SCR, which is the core component of the power supply part. The performance of the selected thyristor will directly affect the performance of the equipment. The commonly used thyristor classification,

1) KP type ordinary thyristor, generally used in rectification;

2) KK type fast thyristor, generally used in inverter;

1. KF type asymmetric thyristor is a new type of thyristor developed in recent years, which is used in series inverter equipment.