A power converter, comprising: a converter section which includes three pairs of switching elements (Srp,..., Stn), each pair having two switching elements connected in series between two output lines (L1, L2), and in which phases of an input three-phase alternating current are connected to nodes between the series-connected switching elements one by one; and a control unit which controls on/off operations of the switching elements (Srp,..., Stn) such that line voltages between a reference phase, which is one of the phases of the input three-phase alternating current, and each of the other phases are output to the two output lines (L1, L2) on a time division basis, wherein each of the switching elements (Srp,..., Stn) is made of a transistor having a bipolar structure; characterized in that the control unit is adapted to select the phase whose voltage has the largest absolute value as a reference phase in each of a first sector in which two phase voltages of the input three-phase alternating current are positive and one phase voltage is negative, and a second sector in which two phase voltages are negative and one phase voltage is positive; provided that one of the phases other than the reference phase whose voltage has an absolute value larger than a voltage of the other phase is the maximum phase, to control, at a predetermined duty cycle (drt, dst), the on/off operation of one of the switching elements (Srp,..., Stn) corresponding to at least the maximum phase to which a forward bias is applied; and to apply a predetermined gate voltage to one or more of the switching elements (Srp,..., Stn) to which a reverse bias is applied. a converter section which includes three pairs of switching elements (Srp,..., Stn), each pair having two switching elements connected in series between two output lines (L1, L2), and in which phases of an input three-phase alternating current are connected to nodes between the series-connected switching elements one by one; and a control unit which controls on/off operations of the switching elements (Srp,..., Stn) such that line voltages between a reference phase, which is one of the phases of the input three-phase alternating current, and each of the other phases are output to the two output lines (L1, L2) on a time division basis, wherein each of the switching elements (Srp,..., Stn) is made of a transistor having a bipolar structure; characterized in that the control unit is adapted to select the phase whose voltage has the largest absolute value as a reference phase in each of a first sector in which two phase voltages of the input three-phase alternating current are positive and one phase voltage is negative, and a second sector in which two phase voltages are negative and one phase voltage is positive; provided that one of the phases other than the reference phase whose voltage has an absolute value larger than a voltage of the other phase is the maximum phase, to control, at a predetermined duty cycle (drt, dst), the on/off operation of one of the switching elements (Srp,..., Stn) corresponding to at least the maximum phase to which a forward bias is applied; and to apply a predetermined gate voltage to one or more of the switching elements (Srp,..., Stn) to which a reverse bias is applied.