The result analysis of the power loss 3-phase induction motor with PWM inverter supply

The purpose of this research is to study the power loss generating of the PWM inverter and the 1 HP 380 V 3-phase squirrel cage induction motor. The test procedure was performed by varying fundamental frequency in the range 25-50 Hz and at constant 1.5 kHz - PWM inverter switching frequency, as a source to the 3-phase 380 V squirrel cage induction motor in star connection with 5.1 N.m constant torque load. The test analysis was to record the input/output voltage/current waveforms by using YOKOGAWA DL1640 storage oscilloscope. Then, using the function FFT program was to determine the variety parameters at each harmonic from those waveforms. The total power loss and efficiency a were calculated by those parameters. The results show the input power is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. But the efficiency is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. The minimum motor power loss is at 35-40 Hz fundamental frequency and the maximum inverter power loss at 81-85% efficiency is around 25-50 Hz fundamental frequency. And also, this is the useful information in designed inverter process to extend the motor´ life due to the overheat from power loss