OVERVOLTAGE PROTECTIVE CIRCUIT FOR SERIES MULTIPLE INVERTER ELEMENT AND SERIES MULTIPLE INVERTER DEVICE

摘要

PURPOSE:To protect the switching elements in a series multiple inverter from overvoltage due to erroneous ignition by connecting each joint of capacitor and diode through a clamp diode with the positive or negative electrode of DC power supply. CONSTITUTION:Upon application of overvoltage onto a transistor 12, charging current flows the circuit of an overvoltage absorbing capacitor 52 and a diode 53. Since the capacitor 52 is initially charged to voltage E through a resistor 55, the overvoltage absorbing capacitor 52 functions, when the collector-emitter voltage of the transistor 12 exceeds the voltage +E, to clamp the collctor- emitter voltage of the transistor 12 to E. By such arrangement, overvoltage due to misfiring of the transistor 12 can be prevented.