A PWM signal generator of a motor controller 100-1 divides, upon occurrence of a condition in which one among a count incrementing period and a count decrementing period for a carrier is greater than or equal to a threshold, in conjunction with a condition in which the other among the count incrementing period and the count decrementing period is less than the threshold, an on time period of any one among a first PWM signal, a second PWM signal, and the third PWM signal into given on time periods and to add a given divided on time period to an energizing time period that is less than the threshold.