Patent ID: 8270186

Claim:
A power converting apparatus, comprising: three input terminals respectively receiving a phase voltage of three-phase AC; three output terminals; first and second DC power supply lines; a converter including a first switch device group including three switch devices connected between each of said input terminals and said first DC power supply line and three switch devices connected between each of said input terminals and said second DC power supply line; a voltage-source inverter including a second switch device group including three switch devices connected between each of said output terminals and said first DC power supply line and three switch devices connected between each of said output terminals and said second DC power supply line, and employing a dead time in switching of said second switch device group; a carrier generating unit generating a carrier showing a triangular wave in which an absolute value of a slope is constant with respect to time; converter gate signal generating units performing commutation of said converter at a timing at which said carrier takes a first reference value for internally dividing an interval from a minimum value to a maximum value of said carrier at a ratio between a first value and a second value; and inverter gate signal generating units, where a first command value is a value smaller by a predetermined value than a second reference value for internally dividing an interval from said first reference value to said maximum value at a ratio between a third value and a fourth value and a second command value is a value larger by said predetermined value than a third reference value for internally dividing an interval from said minimum value to said first reference value at the ratio between said fourth value and said third value, allowing to employ a zero voltage vector as a switching mode of said inverter in a period in which said carrier takes said second command value to said first command value, wherein: an absolute value of said predetermined value is a value obtained by multiplying a difference between said maximum value and said minimum value of said carrier by a length of said dead time to be divided by a cycle of said carrier; and said predetermined value takes a positive value in a case where a load current flowing to the output terminal being kept in conduction with said first DC power supply line in a period sandwiched between periods employing said zero voltage vector flows out of said inverter, and said predetermined value takes a negative value in a case where said load current flows into said inverter.