A device for detecting a phase loss in an output current in an inverter, wherein the inverter includes: an inverting module configured to convert a direct current link voltage to an alternate current voltage, wherein the inverting module includes three-phases legs, wherein each leg has lower and upper switching elements connected in series; and a shunt-resistor connected in series with a lower switching element of each leg of the inverting module, wherein the device includes: an output current detection unit configured to detect two phases output currents from two signals output from two shunt-resistors connected to two phases legs respectively; an output current calculation unit configured to calculate an output current of one remaining phase using the detected two phases output currents; and an output phase loss detection unit configured to detect an output phase loss based on the detected two phases output currents and the calculated output current, wherein the output phase loss detection unit is configured to increase a phase loss count when the calculated output current is within the current band corresponding to the output phase loss and also when the calculated output current has a magnitude equal to and a sign opposite to one of the detected two phases output currents, wherein the output phase loss detection unit is further configured to decrement the phase loss count when the calculated output current is above or below the current band corresponding to the output phase loss and the calculated output current is equal to a sum of the detected two output currents, and wherein the output phase loss detection unit is configured to detect the output phase loss based on the phase loss count. an inverting module configured to convert a direct current link voltage to an alternate current voltage, wherein the inverting module includes three-phases legs, wherein each leg has lower and upper switching elements connected in series; and a shunt-resistor connected in series with a lower switching element of each leg of the inverting module, wherein the device includes: an output current detection unit configured to detect two phases output currents from two signals output from two shunt-resistors connected to two phases legs respectively; an output current calculation unit configured to calculate an output current of one remaining phase using the detected two phases output currents; and an output phase loss detection unit configured to detect an output phase loss based on the detected two phases output currents and the calculated output current, wherein the output phase loss detection unit is configured to increase a phase loss count when the calculated output current is within the current band corresponding to the output phase loss and also when the calculated output current has a magnitude equal to and a sign opposite to one of the detected two phases output currents, wherein the output phase loss detection unit is further configured to decrement the phase loss count when the calculated output current is above or below the current band corresponding to the output phase loss and the calculated output current is equal to a sum of the detected two output currents, and wherein the output phase loss detection unit is configured to detect the output phase loss based on the phase loss count. an output current detection unit configured to detect two phases output currents from two signals output from two shunt-resistors connected to two phases legs respectively; an output current calculation unit configured to calculate an output current of one remaining phase using the detected two phases output currents; and an output phase loss detection unit configured to detect an output phase loss based on the detected two phases output currents and the calculated output current, wherein the output phase loss detection unit is configured to increase a phase loss count when the calculated output current is within the current band corresponding to the output phase loss and also when the calculated output current has a magnitude equal to and a sign opposite to one of the detected two phases output currents, wherein the output phase loss detection unit is further configured to decrement the phase loss count when the calculated output current is above or below the current band corresponding to the output phase loss and the calculated output current is equal to a sum of the detected two output currents, and wherein the output phase loss detection unit is configured to detect the output phase loss based on the phase loss count.