Abstract
Adjustable-speed drives (ASDs) create an opportunity for better use of electric energy. When an ASD is used to control motor speed, motor performance (efficiency and losses) is affected by the switching method employed to control the ASD inverter. Performance measurements were done for a five-hp, three-phase squirrel cage induction motor-ASD set at different loading/speed combinations, and the laboratory testing results were analyzed. Separation of the motor losses was performed and analyzed. This can help determine the effects of harmonically distorted voltage and current waveforms on these losses. This type of analysis can also help derate motors in a way that takes into consideration the total harmonic distortion (THD) of the motor current waveforms. The test results and analysis gave the performance characteristics of the motor, drive, and motor-drive system at different loading/speed points. The separation of motor losses shows that stator, rotor, and core loss increase when an ASD is used to drive the motor. On the other hand, stray load loss decreases. For the tested motor, core loss decreases linearly with the decrease in the ASD's output voltage frequency.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 228-234 |
| Number of pages | 7 |
| Journal | ASHRAE Transactions |
| Volume | 103 |
| Issue number | 1 |
| State | Published - 1997 |
| Event | Proceedings of the 1997 ASHRAE Winter Meeting - Philadelphia, PA, USA Duration: Jan 26 1997 → Jan 29 1997 |
ASJC Scopus subject areas
- Building and Construction
- Mechanical Engineering