Safety and protection when using IGBT high-frequency induction heating equipment

Induction heating uses Faraday's law of electromagnetic induction, placing the heated workpiece in the alternating magnetic field generated by the induction copper coil, and heating the workpiece by means of induced current. The frequency of the alternating current in the induction loop is directly proportional to the intensity of the induced current and inversely proportional to the quenching depth. The specific expression is: the higher the frequency, the greater the induced current, and the shallower the quenching depth; conversely, the lower the frequency, the smaller the induced current, and the thicker the quenching depth. Therefore, when we perform induction heating on different metal materials, we must choose different current frequencies so that the induction heating effect will be better.

Production practice shows that the current frequency range used during induction brazing is wide, and it can generally be selected between 10-460KHz. At present, IGBT high-frequency induction heating power supply is most suitable. The most effective protection for high-frequency heating power supplies is to effectively shield the electromagnetic fields leaked from them. Generally, overall shielding is used, that is, high-frequency equipment, feeders, induction coils, etc. are placed in a shielded room. It is best for operators to operate in a shielded room. The walls of the shielded room are generally made of aluminum plates, copper plates or steel plates, and the plate thickness is generally 1.2-1.5mm. During operation, movable doors or windows can be installed in the required parts.

In addition, in order to ensure the working safety of high-frequency induction heating equipment, correct use of the operating methods of IGBT high-frequency induction heating equipment can avoid human operating errors and bring unnecessary trouble to your own production. First of all, it is required that the chassis must be installed with a dedicated ground wire. The power supply is generally three-phase three-wire 380V, and the grounding resistance must be less than 4Ω. Around the equipment, especially at the worker's operating position, insulating rubber sheets with a voltage of 35kv must be laid. Next, be sure to boot in strict order. Before starting the operation of the equipment, carefully check the cooling water system. If there is any abnormality, check it; only when the water cooling system is working normally, the oscillation tube is allowed to be powered on to preheat. Equipment maintenance generally does not allow live operation. If live maintenance is really necessary, the operator must wear insulating shoes and gloves, and must be supervised by a dedicated person. When maintenance is required, the main power switch must be cut off and each capacitor bank must be discharged with a discharge rod before maintenance work is allowed. When the work is completed, to stop the heating operation, first turn off the "control switch" of the main unit, that is, the panel, and then turn off the power distribution air switch.