Investigation of Harmonic Distortion for Frequently Changing Input Voltage

This paper present the concept of improving harmonic distortion in power systems. Investigations were carried out for studying the effect of range dependent voltage switching and random voltage switching (sudden changes) in the input line voltage on the harmonic distortion at the output of the system. The analysis of the results showed that the insulated gate bipolar transistor (IGBT) based power system using the concept of switching resistor is capable of reducing harmonic distortion on the input power lines introduced because of external or internal load conditions. Harmonic distortions in the input and output of the conventional systems are estimated and compared. Reduction in the total harmonic distortion (THD) was also investigated for the proposed IGBT based power system.