Inverter intermediate frequency furnaces must have advantages over parallel intermediate frequency furnaces

1. The thyristor parallel circuit is a parallel resonance intermediate frequency furnace. During the melting process, especially for melting aluminum, copper and other materials, the load is very light, and its power output is very small, which has a lot to do with the nature of the load, so its melting speed is slow , Difficulty in heating up. The thyristor series intermediate frequency melting furnace adjusts the power through frequency modulation, so it is relatively less affected by the nature of the load. The whole process of smelting almost maintains a constant power output. Because it is series resonance, that is, voltage resonance, the induction coil voltage is high and the current is small, so The power loss is small.

2. Because it is a series inverter, the power factor is high and the harmonics are small, so there is no need to install a reactive power compensation device. This can save users a lot of money, and it is also an advanced equipment that the power supply department vigorously promotes.

3. When the series intermediate frequency furnace is working, the rectifier always works in the fully-on state, and the output power of the inverter circuit is changed by controlling the inverter trigger pulse frequency. And the load current is a sine wave, so the series intermediate frequency furnace will not seriously pollute the power grid with high harmonics, and the power factor is high. Parallel inverters cannot achieve one-to-two automatic power adjustment operation, because the power adjustment of the parallel inverter power supply can only be achieved by adjusting the output voltage of the rectifier bridge. When the parallel inverter rectifier bridge works at low voltage, the rectifier conduction angle is very small. In the state, the power factor of the equipment will be very low, and the parallel inverter load current is a square wave, which will seriously pollute the grid. If the power is adjusted by adjusting the inverter back pressure angle, the power adjustment range is very narrow. Therefore, parallel inverter power supplies cannot achieve one-to-two operation.