Parallel resonance induction melting furnace, in the melting process, its power output has a great relationship with the load, its melting speed is slow, and it is difficult to heat up. Series resonance intermediate frequency smelting furnace adjusts power through frequency modulation, which is relatively less affected by the nature of the load. The whole process of smelting almost maintains constant power output. Because it is series resonance, that is, voltage resonance, the induction coil voltage is high and the current is small, so power loss It's small, it melts fast and heats up fast.
Because it is a series inverter, the power factor is high, and the harmonics are small, so there is no need to install reactive power compensation devices. This can save users a lot of money, and it is also an advanced equipment that the power supply department vigorously promotes.
When the series inverter induction melting 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 inverter induction melting furnace will not seriously pollute the 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 induction melting furnace 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 In a very small 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, so parallel inverter induction melting furnaces cannot achieve one-to-two operation.
