INVERTER DEVICE

摘要

An inverter device (1) comprises: an inverter circuit (2) connected to a DC power source (10) for converting DC power to AC power by alternately switching two sets of switching elements (Q1 - Q4) on and off in each predetermined cycle; a clamping circuit (3) configured of at least one switching element (Q5 - Q6) connected between two output terminals of the inverter circuit; and a control unit (5) for controlling switching on and off of the switching elements of the inverter circuit and the clamping circuit, and the control unit (5) short-circuits the clamping circuit when it switches off all of the two sets of the switching element at least in the vicinity of zero-cross point of AC voltage, thereby enables to control an electric current even when polarity (or sign) of the AC voltage and polarity (or sign) of the output current are inconsistent with each other.