A motor drive apparatus configured to drive a motor, comprising: inverter modules (5, 6, 7) equivalent in number to phases of the motor, the inverter modules (5, 6, 7) each including a plurality of switching element pairs (5a, 5b; 5c, 5d; 5e, 5f) connected in parallel, each of the inverter modules having an upper arm defined by a set of switching elements (5a,5c,5e) and a lower arm defined by a set of switching elements (5b,5d,5f), each of the switching element pairs (5a, 5b; 5c, 5d; 5e, 5f) including two switching elements connected in series, the series-connected two switching elements (5a,5b;5c,5d;5e,5f) of each switching pair being a switching element (5a;5c;5e) included in the set of switching elements of the upper arm and a switching element (5b;5d;5f) included in the set of switching elements of the lower arm; a control unit configured to generate a PWM signal used to drive the inverter modules (5, 6, 7) with PWM; a drive control unit configured to generate, for each of the inverter modules (5, 6, 7), an individual PWM signal for each of the switching elements (5a, 5b; 5c, 5d; 5e, 5f) of a corresponding one of the inverter modules (5, 6, 7) on a basis of the PWM signal generated by the control unit; and a current measurement unit connected to the set of the switching elements of each of the upper and lower arms of each inverter module characterized in that: the drive control unit is configured to control the switching elements to turn on the switching elements of each arm of each inverter module one-by-one while the motor is not operating, such that the current measurement unit detects a current flowing through the switching element turned on and the drive control unit obtains a ratio of on-resistances of the switching elements of each arm on a basis of the detected current; and the drive control unit is configured to calculate a current flowing through each switching element of each arm on a basis of the ratio of on-resistances and a sum of currents flowing through the switching elements of each arm, the sum of currents being detected by the current measurement unit while the motor is operating; the drive control unit is configured to adjust a pulse width of the individual PWM signal on a basis of a difference in values of the currents flowing through the switching elements of each arm. inverter modules (5, 6, 7) equivalent in number to phases of the motor, the inverter modules (5, 6, 7) each including a plurality of switching element pairs (5a, 5b; 5c, 5d; 5e, 5f) connected in parallel, each of the inverter modules having an upper arm defined by a set of switching elements (5a,5c,5e) and a lower arm defined by a set of switching elements (5b,5d,5f), each of the switching element pairs (5a, 5b; 5c, 5d; 5e, 5f) including two switching elements connected in series, the series-connected two switching elements (5a,5b;5c,5d;5e,5f) of each switching pair being a switching element (5a;5c;5e) included in the set of switching elements of the upper arm and a switching element (5b;5d;5f) included in the set of switching elements of the lower arm; a control unit configured to generate a PWM signal used to drive the inverter modules (5, 6, 7) with PWM; a drive control unit configured to generate, for each of the inverter modules (5, 6, 7), an individual PWM signal for each of the switching elements (5a, 5b; 5c, 5d; 5e, 5f) of a corresponding one of the inverter modules (5, 6, 7) on a basis of the PWM signal generated by the control unit; and a current measurement unit connected to the set of the switching elements of each of the upper and lower arms of each inverter module characterized in that: the drive control unit is configured to control the switching elements to turn on the switching elements of each arm of each inverter module one-by-one while the motor is not operating, such that the current measurement unit detects a current flowing through the switching element turned on and the drive control unit obtains a ratio of on-resistances of the switching elements of each arm on a basis of the detected current; and the drive control unit is configured to calculate a current flowing through each switching element of each arm on a basis of the ratio of on-resistances and a sum of currents flowing through the switching elements of each arm, the sum of currents being detected by the current measurement unit while the motor is operating; the drive control unit is configured to adjust a pulse width of the individual PWM signal on a basis of a difference in values of the currents flowing through the switching elements of each arm. the drive control unit is configured to control the switching elements to turn on the switching elements of each arm of each inverter module one-by-one while the motor is not operating, such that the current measurement unit detects a current flowing through the switching element turned on and the drive control unit obtains a ratio of on-resistances of the switching elements of each arm on a basis of the detected current; and the drive control unit is configured to calculate a current flowing through each switching element of each arm on a basis of the ratio of on-resistances and a sum of currents flowing through the switching elements of each arm, the sum of currents being detected by the current measurement unit while the motor is operating; the drive control unit is configured to adjust a pulse width of the individual PWM signal on a basis of a difference in values of the currents flowing through the switching elements of each arm.