Inverter apparatus provided with electric discharge control circuit of DC smoothing capacitor and method of controlling the same

摘要

In a variable frequency power source unit, a series circuit of a contractless semiconductor switching element (11) and a resistor (10) is provided in parallel to a d.c. smoothing capacitor (3) and a control circuit (12) is provided for receiving a signal for turning on the switching element (11) selectively at any time after the power source is interrupted thereby discharging the electric charge of the d.c. smoothing capacitor (3).