A motor driving apparatus comprising: an inverter having a plurality of switching devices, wherein the inverter converts a direct current power into an alternating current power according to switching of the switching devices and supplies the AC power to a motor; and a controller to control the inverter, wherein the controller: performs a control operation such that a switching frequency of the respective switching devices of the inverter remains constant in a first mode corresponding to a motor operation mode; and performs a control operation to change the switching frequency of the respective switching devices of the inverter, in a second mode corresponding to a sound output mode for fault diagnosis, to output sound corresponding to the changed switching frequency wherein the controller performs a control operation to output sound containing diagnostic data in the second mode, wherein the controller comprises: a frequency transformer to transform a frequency of sound to be output; a data insertion unit to insert the diagnostic data into a frequency-transformed audio signal; an inverse transformer to inversely transform the audio signal containing the diagnostic data; and a multiplexer to multiplex the inversely transformed audio signal, wherein the controller changes the switching frequency of the respective switching devices of the inverter based on the multiplexed audio signal. an inverter having a plurality of switching devices, wherein the inverter converts a direct current power into an alternating current power according to switching of the switching devices and supplies the AC power to a motor; and a controller to control the inverter, wherein the controller: performs a control operation such that a switching frequency of the respective switching devices of the inverter remains constant in a first mode corresponding to a motor operation mode; and performs a control operation to change the switching frequency of the respective switching devices of the inverter, in a second mode corresponding to a sound output mode for fault diagnosis, to output sound corresponding to the changed switching frequency wherein the controller performs a control operation to output sound containing diagnostic data in the second mode, wherein the controller comprises: a frequency transformer to transform a frequency of sound to be output; a data insertion unit to insert the diagnostic data into a frequency-transformed audio signal; an inverse transformer to inversely transform the audio signal containing the diagnostic data; and a multiplexer to multiplex the inversely transformed audio signal, wherein the controller changes the switching frequency of the respective switching devices of the inverter based on the multiplexed audio signal. performs a control operation such that a switching frequency of the respective switching devices of the inverter remains constant in a first mode corresponding to a motor operation mode; and performs a control operation to change the switching frequency of the respective switching devices of the inverter, in a second mode corresponding to a sound output mode for fault diagnosis, to output sound corresponding to the changed switching frequency wherein the controller performs a control operation to output sound containing diagnostic data in the second mode, wherein the controller comprises: a frequency transformer to transform a frequency of sound to be output; a data insertion unit to insert the diagnostic data into a frequency-transformed audio signal; an inverse transformer to inversely transform the audio signal containing the diagnostic data; and a multiplexer to multiplex the inversely transformed audio signal, wherein the controller changes the switching frequency of the respective switching devices of the inverter based on the multiplexed audio signal. a frequency transformer to transform a frequency of sound to be output; a data insertion unit to insert the diagnostic data into a frequency-transformed audio signal; an inverse transformer to inversely transform the audio signal containing the diagnostic data; and a multiplexer to multiplex the inversely transformed audio signal, wherein the controller changes the switching frequency of the respective switching devices of the inverter based on the multiplexed audio signal.