SNUBBER CIRCUIT FOR GTO THYRISTOR

摘要

PURPOSE:To protect a GTO thyristor while ensuring the operation and to miniaturize the circuit by connecting a series body comprising a capacitor and a diode in parallel with the GTO thyristor and connecting a series body comprising a resistor and the thyristor in parallel with the diode. CONSTITUTION:The series body comprising the capacitor 3 and the diode 2 is connected in parallel with the GTO thyristor 1 of a snubber circuit and a series body comprising a resistor 4 and the thyristor 5 is connected in parallel with the diode 2. The forward direction of the GTO thyristor 1 and the thyristor 5 is taken the same and the forward direction of the diode 2 and the thyristor 5 is reversed. The gate of the GTO thyristor 1 and the thyristor 5 is controlled synchronously by a control circuit. Then when the ripple between the cathode and anode is large with the GTO thyristor 1 turned off, the discharge of the capacitor 3 through the capacitor 3 is blocked by the thyristor 5, the GTO thyristor 1 is protected while its operation is ensured and the circuit is miniaturized.