A power conversion device, comprising: an alternating current rotating machine (1a to 1d) having first multi-phase windings (U1, V1, W1) and second multi-phase windings (U2, V2, W2); a direct current power supply; a voltage command calculation unit (6, 6a to 6e) configured to output a first voltage command and second voltage command; switching signal generating means (5a to 5k) configured to output a first switching signal based on the first voltage command and output a second switching signal based on the second voltage command; first power conversion means configured to convert direct current voltage of the direct current power supply based on the first switching signal and apply voltage to the first multi-phase windings (U1, V1, W1); second power conversion means configured to convert direct current voltage of the direct current power supply based on the second switching signal and apply voltage to the second multi-phase windings (U2, V2, W2); first current detection means configured to detect a first bus current, which is current flowing between the direct current power supply and first power conversion means; first phase current calculation means configured to calculate the current flowing through the first multi-phase windings (U1, V1, W1) of the alternating current rotating machine (1a to 1d) based on the detected first bus current, wherein the first current detection means is configured to detect the first bus current at a timing at which a first non-zero voltage vector, whose components represent voltages applied to the respective first multi-phase windings (U1, V1, W1) based on the first switching signal, and a second non-zero voltage vector, whose components represent voltages applied to the respective second multi-phase windings (U2, V2, W2) based on the second switching signal, either: (i) coincide with one another in a case where the second switching signal is the same as the first switching signal and the first and second multi-phase windings have no phase difference therebetween; or (ii) neighbor one another so as to have a phase difference therebetween which is smaller than a phase difference between the first non-zero voltage vector and any other voltage vector whose components represent voltages applied to the respective second multi-phase windings (U2, V2, W2) based on the second switching signal in a case where the second switching signal is different to the first switching signal and the first and second multi-phase windings have a phase difference therebetween. an alternating current rotating machine (1a to 1d) having first multi-phase windings (U1, V1, W1) and second multi-phase windings (U2, V2, W2); a direct current power supply; a voltage command calculation unit (6, 6a to 6e) configured to output a first voltage command and second voltage command; switching signal generating means (5a to 5k) configured to output a first switching signal based on the first voltage command and output a second switching signal based on the second voltage command; first power conversion means configured to convert direct current voltage of the direct current power supply based on the first switching signal and apply voltage to the first multi-phase windings (U1, V1, W1); second power conversion means configured to convert direct current voltage of the direct current power supply based on the second switching signal and apply voltage to the second multi-phase windings (U2, V2, W2); first current detection means configured to detect a first bus current, which is current flowing between the direct current power supply and first power conversion means; first phase current calculation means configured to calculate the current flowing through the first multi-phase windings (U1, V1, W1) of the alternating current rotating machine (1a to 1d) based on the detected first bus current, wherein the first current detection means is configured to detect the first bus current at a timing at which a first non-zero voltage vector, whose components represent voltages applied to the respective first multi-phase windings (U1, V1, W1) based on the first switching signal, and a second non-zero voltage vector, whose components represent voltages applied to the respective second multi-phase windings (U2, V2, W2) based on the second switching signal, either: (i) coincide with one another in a case where the second switching signal is the same as the first switching signal and the first and second multi-phase windings have no phase difference therebetween; or (ii) neighbor one another so as to have a phase difference therebetween which is smaller than a phase difference between the first non-zero voltage vector and any other voltage vector whose components represent voltages applied to the respective second multi-phase windings (U2, V2, W2) based on the second switching signal in a case where the second switching signal is different to the first switching signal and the first and second multi-phase windings have a phase difference therebetween. (i) coincide with one another in a case where the second switching signal is the same as the first switching signal and the first and second multi-phase windings have no phase difference therebetween; or (ii) neighbor one another so as to have a phase difference therebetween which is smaller than a phase difference between the first non-zero voltage vector and any other voltage vector whose components represent voltages applied to the respective second multi-phase windings (U2, V2, W2) based on the second switching signal in a case where the second switching signal is different to the first switching signal and the first and second multi-phase windings have a phase difference therebetween.