Analysis of the causes of thyristor (SCR) burnout
The MF induction melting furnace uses the principle of electromagnetic induction to heat the metal, and the metal inside the coil is heated by the frequency conversion device and the induction coil to achieve the purpose of heating or melting. Thyristor is the main component of the frequency conversion device, once the electric furnace is burned out, it cannot operate. It is necessary to investigate the reason for the burning of the SCR and repair it.
- High-voltage silicon burning (inverter failure, reduced component voltage resistance, poor cooling effect, reduced system insulation performance, and short circuit of the intermediate frequency electric furnace to the ground will cause the intermediate frequency electric furnace to burn silicon.)
- For high-current silicon burning, check the back pressure angle of the intermediate frequency electric furnace voltage and whether the trigger circuit is in poor contact.
- Check the resistance-capacitance absorption circuit of the inverter silicon of the intermediate frequency electric furnace, and check whether the absorption capacitor is open. Also check whether the electrical parameters of the SCR meet the requirements.
- Whether the water-cooling jacket of the thyristor and other cooling water circuits are blocked, whether the induction coil is ignited to the ground, this situation will form a sudden high voltage and cause the thyristor to breakdown and damage.
The above is the reason for the burning of silicon in the intermediate frequency electric furnace. Find the source of the problem, replace the thyristor, check the system again, and restart after confirming that there is no fault to avoid secondary burning.