Keywords : Modified Sine Wave
Engineering and Technology Journal,
2010, Volume 28, Issue 2, Pages 399-415
This paper presents the performance of a modified sine wave voltage source
inverter with duty cycle. Evaluation of quality factors like the Total Harmonic
Distortion THD of the output voltage for various values of switching-on angle α
indicates that the minimum harmonic distortion occurs at α=23.2180, where the
THD is 28.96%, about 60% of that of the square wave. The 3rd harmonic is about
12.61% of the fundamental, and about third of the square wave.
The current paper, illustrates the inverter waveforms and how different types
of loads behave when operating from them. Therefore, the THD of the output
current depends on the load types. Results of typical load types are presented.
No heavy filters or complex timing circuits are necessary; therefore, the
resulting inverter is smaller, lighter weight, and simpler, implying greater
reliability and lower cost. These advantages invite a closer look at inverter-motor
systems. Variations in induction motor performance may occur when the motor is
driven from a modified sine wave inverter rather than a sine wave source.