Three level Space Vector Pulse Width Modulation without even order harmonics fit for asymmetrical uniform sampling

Abstract

For three level Space Vector Pulse Width Modulation (SVPWM), it is important to make sure that the phase voltage will not change by two levels in one time. It is found out that some even order harmonic elimination PWM method may cause the phase voltage to jump by two steps when asymmetrical uniform sampling technique is used. The condition when two-level voltage jump happens is found out. A new three level SVPWM containing no even order harmonics suitable for asymmetrical sampling is provided. Both simulation and experiment of the new SVPWM show that no two-level voltage jump happens and the even harmonics are eliminated.

Research on a New Type of Plating Power Supply

“…When adopting diode rectifying method, it cause current waveform serious distortion, phase delay, lots of harmonics and can't stabilize the output voltage [5] . Plating power supply generally adopts thyristor phase-control rectifier, volume is big, efficiency and power factor are low, output current ripples are big [6] . Three-level PWM rectifier can make the phases of current and voltage in the ac side remain synchronous, its waveform is very similar to the sine wave [8] .…”