Apparatus and method for controlling inverter for driving motor

An apparatus for controlling an inverter for driving a motor, the apparatus comprising a processor which includes:

• a current processor for generating a voltage command for causing a current detection value obtained by measuring a current supplied from the inverter to the motor to follow a current command for driving the motor;
• a voltage modulator for generating a pulse width modulation signal for controlling on and off states of switching elements in the inverter with a predetermined switching frequency based on the voltage command;
• and
• a frequency determining processor for setting a frequency change range which is a range within which the switching frequency is randomly changed, and for randomly determining the switching frequency within the frequency change range when a random pulse width modulation method is applied to control of the inverter,
• wherein the frequency determining processor applies the random pulse width modulation method or stops application of the random pulse width modulation method by gradually increasing or decreasing the frequency change range.