A three-phase rectifier that converts three-phase alternating current power supplied from a three-phase AC power supply into direct current power, the three-phase rectifier comprising: a full-wave rectifier circuit including a plurality of diodes that rectify three-phase AC power to DC power; a bidirectional switch circuit that switches on and off inputs of respective phases from the three-phase AC power supply to the full-wave rectifier circuit; and a controller (5, 6) that detects voltages of the respective phases of the three-phase AC power supply, generates switching patterns for the respective phases to switch the bidirectional switch circuit on and off based on the voltages of the phases, and controls switching of the bidirectional switch circuit based on the switching patterns, wherein the controller divides the three-phase AC power into consecutive modes I to VI according to magnitude relation of the voltages of the respective phases and generates different switching patterns for the respective phases in each mode, characterized in that the switching patterns are the same in mode I and IV, in mode II and V and in mode III and VI, the switching patterns having switching cycles in each mode consisting of consecutively switching off, on, and off a pulse of a first one of the phases, consecutively switching on, off and on a pulse of a second one of the phases, consecutively switching on and off a pulse of a third one of the phases; a period in which the bidirectional switch circuit is switched off for at least two phases at the end of each switching cycle being introduced by inserting zero voltage to the switching pattern for the first one of the phases to introduce said period. a full-wave rectifier circuit including a plurality of diodes that rectify three-phase AC power to DC power; a bidirectional switch circuit that switches on and off inputs of respective phases from the three-phase AC power supply to the full-wave rectifier circuit; and a controller (5, 6) that detects voltages of the respective phases of the three-phase AC power supply, generates switching patterns for the respective phases to switch the bidirectional switch circuit on and off based on the voltages of the phases, and controls switching of the bidirectional switch circuit based on the switching patterns, wherein the controller divides the three-phase AC power into consecutive modes I to VI according to magnitude relation of the voltages of the respective phases and generates different switching patterns for the respective phases in each mode, characterized in that the switching patterns are the same in mode I and IV, in mode II and V and in mode III and VI, the switching patterns having switching cycles in each mode consisting of consecutively switching off, on, and off a pulse of a first one of the phases, consecutively switching on, off and on a pulse of a second one of the phases, consecutively switching on and off a pulse of a third one of the phases; a period in which the bidirectional switch circuit is switched off for at least two phases at the end of each switching cycle being introduced by inserting zero voltage to the switching pattern for the first one of the phases to introduce said period. the switching patterns having switching cycles in each mode consisting of consecutively switching off, on, and off a pulse of a first one of the phases, consecutively switching on, off and on a pulse of a second one of the phases, consecutively switching on and off a pulse of a third one of the phases; a period in which the bidirectional switch circuit is switched off for at least two phases at the end of each switching cycle being introduced by inserting zero voltage to the switching pattern for the first one of the phases to introduce said period.