The induction melting furnace power supply is difficult to start, the reactor vibration is large, and the sound is dull
Fault analysis and processing are as follows:
a. There is a thyristor damaged in the inverter circuit. When a thyristor is damaged in the inverter circuit, the device can sometimes be started, but the above failure phenomenon will occur after startup, replace the damaged thyristor, and check the cause of the damage.
b. The inverter thyristor has a non-conducting, that is, "three legs" work. It is possible that the thyristor gate is open at this time, or the wires connected thereto are loose and have poor contact.
c. The IF signal sampling loop has an open circuit or a polarity error. This reason is mostly caused by the intersection angle method, the intermediate frequency voltage signal is open or the polarity of the intermediate frequency voltage signal is reversed when repairing other faults.
d. The inverter leads the front angle phase shifting circuit to malfunction. The load of the IF power supply is capacitive, ie the current is ahead of the voltage. In the sampling control circuit, a phase shifting circuit is designed, which may also be caused if the phase shifting circuit fails.
