THREE-PHASE AC/DC CONVERTING APPARATUS AND AIR HANDLING UNIT USING THREE-PHASE AC/DC CONVERTING APPARATUS

摘要

The objective of the invention is to provide a three-phase AC/DC converting unit, which can suppress noises and leakage currents of harmonics, and an air handling unit using the three-phase AC/DC converting unit. There are included: a three-phase AC power supply; a three-phase rectifying bridge circuit in which rectifying elements connected to the three-phase AC power supply are bridge-connected to one another; a three-phase full-bridge circuit that comprises reverse blocking diodes that are connected in parallel to the respective ones of two mutually series-connected switching elements that are connected to the output side of the three-phase rectifying bridge circuit for each of the three phases; reactors that connect the three-phase AC power supply to the three-phase full-bridge circuit; a smoothing capacitor that is connected to the output side of the three-phase full-bridge circuit; a DC voltage detecting means that detects an output voltage; a power supply phase detecting means that detects the power supply phases of the three-phase AC power supply; and a pulse width modulating means that outputs PWM signals for controlling the switching elements. The pulse width modulating means outputs the PWM signals on the basis of the power supply phases and the output voltage.