Cause and treatment of Capacitor explosion(II)

The existence of harmonic current

The high power SCR rectifier is used as the DC power supply of rotary kiln and the compensation screen in parallel operation. The thyristor connected to the power grid plays the role of a high order harmonic generator objectively, which will cause the waveform distortion of the circuit voltage and current. The existence of harmonic current often makes the capacitor produce abnormal sound, and when it is serious, it causes the capacitor to expand, which is the third reason that causes the capacitor to explode. The main reason for this is that the high order harmonic current is superimposed on the fundamental current, which increases the total current of the capacitor and causes a parallel resonance between the reactance of the system and the capacitive reactance of the capacitor. The current flowing into the capacitor is multiplied by three times) the capacitor has a local series resonance to a higher harmonic, which causes overload.