POWER CONVERSION DEVICE

摘要

A power conversion device converts an AC power source to a DC power and drives a DC load or further converts the DC power to a pseudo AC power having arbitrary frequency and amplitude and drives an AC load. In the power conversion device, a resistor is inserted between the output terminal on the cathode side of a rectifying diode bridge and a semiconductor switching circuit for improving a power factor. Both sides of the resistor are connected to inverting and level-shifting circuits for performing inverting and level-shifting, respectively, and the outputs of the respective inverting and level-shifting circuits are input to a differential circuit, thereby obtaining current detection information from the output of an actuation circuit. Using the current detection information, the semiconductor switching circuit is on/off controlled.