The frequency conversion steps of high frequency electronic frequency converter are as follows.
The three-phase power frequency current is supplied to the primary winding of the transformer after being filtered and then converted into the high-voltage alternating current of 50Hz and voltage of 10000V after being stepped up by the transformer. Old-fashioned equipment uses high-voltage transformers, while new devices use inductive regulators. The structure of the induction voltage regulator is similar to a large vertical wire wound asynchronous motor, and the voltage stepless adjustment can be realized by changing the relative displacement of the rotor and the stator.
The pressure-regulated high-voltage AC, through rectification into high-voltage DC. The old-fashioned equipment uses full-wave thyristor rectifier, the new device uses high-voltage silicon reactor three-phase bridge full-wave rectifier.
Oscillation (frequency conversion)
The high-voltage DC output from the rectifier supplies the high-voltage pulsed DC current to the oscillating tube at a frequency of about 20 kHz. After oscillated, it becomes a high-voltage alternating current with a frequency of 200 to 300 kHz. After being stepped down by a high-frequency transformer, it can be used as the power supply for the furnace.