A power supply apparatus, comprising: a three-phase alternating current power supply; first reactors (2, 3, 4) each provided for a corresponding phase of the three-phase alternating current power supply; a first diode bridge rectifier circuit connected to the three-phase alternating current power supply via the first reactors (2, 3, 4) and provided with a plurality of diodes (5a, 5b, 5c, 5d, 5e, 5f); and a smoothing capacitor which is connected to direct current output terminals of the first bridge rectifier circuit in parallel, and which is for supply of direct voltage to a load, characterized in that the power supply apparatus includes second reactors (7, 8, 9) respectively provided for alternating current input terminals (u 1, v 1, w 1) of corresponding phases of the first bridge rectifier circuit; a second diode bridge rectifier circuit having alternating current input terminals (u 2, v 2, w 2) which are connected to the alternating current input terminals (u 1, v 1, w 1) of the first diode bridge rectifier circuit via the second reactors (7, 8, 9), wherein the direct current output terminals of the first diode bridge rectifier circuit are further connected to direct current output terminals of the second diode bridge rectifier circuit in parallel, and configured to connect to a load in parallel, and wherein the power supply apparatus further comprises three capacitors (10, 11, 12) each of which is connected between a respective pair of terminals of the alternating current input terminals of the second diode bridge rectifier circuit, wherein the second reactors (7, 8, 9) and the capacitors (10, 11, 12) are provided between the alternating current input terminals (u 1, v 1, w 1) of the first diode bridge rectifier circuit and the alternating current input terminals (u 2, v 2, w 2) of the second diode bridge rectifier circuit. a three-phase alternating current power supply; first reactors (2, 3, 4) each provided for a corresponding phase of the three-phase alternating current power supply; a first diode bridge rectifier circuit connected to the three-phase alternating current power supply via the first reactors (2, 3, 4) and provided with a plurality of diodes (5a, 5b, 5c, 5d, 5e, 5f); and a smoothing capacitor which is connected to direct current output terminals of the first bridge rectifier circuit in parallel, and which is for supply of direct voltage to a load, characterized in that the power supply apparatus includes second reactors (7, 8, 9) respectively provided for alternating current input terminals (u 1, v 1, w 1) of corresponding phases of the first bridge rectifier circuit; a second diode bridge rectifier circuit having alternating current input terminals (u 2, v 2, w 2) which are connected to the alternating current input terminals (u 1, v 1, w 1) of the first diode bridge rectifier circuit via the second reactors (7, 8, 9), wherein the direct current output terminals of the first diode bridge rectifier circuit are further connected to direct current output terminals of the second diode bridge rectifier circuit in parallel, and configured to connect to a load in parallel, and wherein the power supply apparatus further comprises three capacitors (10, 11, 12) each of which is connected between a respective pair of terminals of the alternating current input terminals of the second diode bridge rectifier circuit, wherein the second reactors (7, 8, 9) and the capacitors (10, 11, 12) are provided between the alternating current input terminals (u 1, v 1, w 1) of the first diode bridge rectifier circuit and the alternating current input terminals (u 2, v 2, w 2) of the second diode bridge rectifier circuit.