The role of the electric heating capacitor of the intermediate frequency furnace
In the intermediate frequency furnace power supply, there are many components that play different roles. These components include: capacitors, thyristors, reactors, mine cables, induction coils, etc. Electric heating capacitors are mainly used in controllable or adjustable AC voltage systems with rated voltage not greater than 4.8kv and frequency below 100khz, and are specially used to improve the power factor of induction heating, melting, casting equipment, and similar equipment.
1. Main technical parameters of electric heating capacitors
Capacitance deviation: ±10%, the ratio of the value of each equal group capacitor to the minimum value is not greater than 1.1.
Dielectric loss tangent value tanδ (full film dielectric) at rated voltage Un, 20℃:
Un≤1kV: tanδ≤0.0015
Un＞1kV: tanδ≤0.0012
2. Insulation strength
Can withstand 1kV power frequency test voltage for 1min
3. Cooling water inlet temperature
The cooling water inlet temperature does not exceed 30 ℃
Capacitors with Qn≤1000kvar, water flow≥4L/min
Capacitors with Qn ≥ 1000kvar, water flow ≥ 6L/min
4. Equipment installation environment
The altitude does not exceed 1000m.
The ambient air temperature in the installation and operation area is not higher than 50 ℃.
The installation site has no severe mechanical vibration, no harmful gas and vapor and no explosive dust
5. Capacitor structure
The electric heating capacitor consists of the following main parts. The core consists of several parallel components. The capacitor components are rolled from capacitor paper (medium) and aluminum conductor (plate). The element pole plates are all protruding out of the medium, and one pole plate is welded with the cooling water pipe, and is connected with the grounding stud or grounding plate on the cover through the cooling water pipe, which is the total outlet of the pole plate. The second pole plate is insulated from the shell, connected with the guide rod by a connecting piece, and drawn out through the porcelain sleeve on the cover.
