The motor loss consists of mechanical loss, copper
loss and iron loss. Both the last two consist in stator and
rotor and these combinations consist of fundamental,
space harmonics and time harmonics components. Space
harmonics component is caused by teeth arrangement,
primary coil winding and rotor bar arrangement. Time
harmonics component is caused by PWM inverter output
waveform. Therefore, motor loss components of
W , and loss simusoidal W , are shown in Table IV. The
motor loss increment by PWM inverter drive is also
shown as their deviation. Mechanical loss can be
removed in the condition that the rotating velocity of
sinusoidal wave source is the same as the one of PWM
inverter.