A power conversion device comprising: a set of pairs of serially connected main circuit switching elements that supply power to a load wherein the pairs are connected in parallel with a DC voltage source; a respective free-wheel diode being connected in anti-parallel fashion with each of said main circuit switching elements; and a reverse voltage application circuit (7, 7a, 7b) that applies reverse voltage smaller than a voltage of said DC voltage source to said free-wheel diode on cut-off of said free-wheel diode, wherein said reverse voltage application circuit (7, 7a, 7b) is constituted by a series circuit comprising: (a) an auxiliary power source (12, 12a, 12b) of lower voltage than the voltage of said DC voltage source; and (b) (i) a reverse voltage application switching element (17, 17a, 17b) having lower voltage withstanding ability than said main circuit switching element, that is turned ON during reverse recovery of said free-wheel diode; and (ii) a high-speed auxiliary diode (16, 29a, 29b) of shorter recovery time than said free-wheel diode; and wherein said auxiliary power source (12, 12a, 12b) comprises: (i) a low voltage DC voltage power source (8, 8a, 8b) having lower voltage than the voltage of said DC voltage source; (ii) a current suppression circuit that suppresses said main circuit current flowing in said low-voltage DC voltage power source (8, 8a, 8b) on reverse recovery of said free-wheel diode, and that is connected in series with said low-voltage DC voltage power source (8, 8a, 8b), and (iii) a high frequency capacitor (15A, 32a, 32b) having low internal impedance even in a high frequency band, connected in parallel with series circuit of said low-voltage DC voltage power source (8, 8a, 8b) and said current suppression circuit. a set of pairs of serially connected main circuit switching elements that supply power to a load wherein the pairs are connected in parallel with a DC voltage source; a respective free-wheel diode being connected in anti-parallel fashion with each of said main circuit switching elements; and a reverse voltage application circuit (7, 7a, 7b) that applies reverse voltage smaller than a voltage of said DC voltage source to said free-wheel diode on cut-off of said free-wheel diode, (a) an auxiliary power source (12, 12a, 12b) of lower voltage than the voltage of said DC voltage source; and (b) (i) a reverse voltage application switching element (17, 17a, 17b) having lower voltage withstanding ability than said main circuit switching element, that is turned ON during reverse recovery of said free-wheel diode; and (ii) a high-speed auxiliary diode (16, 29a, 29b) of shorter recovery time than said free-wheel diode; and (i) a reverse voltage application switching element (17, 17a, 17b) having lower voltage withstanding ability than said main circuit switching element, that is turned ON during reverse recovery of said free-wheel diode; and (ii) a high-speed auxiliary diode (16, 29a, 29b) of shorter recovery time than said free-wheel diode; and (i) a low voltage DC voltage power source (8, 8a, 8b) having lower voltage than the voltage of said DC voltage source; (ii) a current suppression circuit that suppresses said main circuit current flowing in said low-voltage DC voltage power source (8, 8a, 8b) on reverse recovery of said free-wheel diode, and that is connected in series with said low-voltage DC voltage power source (8, 8a, 8b), and (iii) a high frequency capacitor (15A, 32a, 32b) having low internal impedance even in a high frequency band, connected in parallel with series circuit of said low-voltage DC voltage power source (8, 8a, 8b) and said current suppression circuit.