PULSATING DC LINK THREE-PHASE INVERTERS

Sinusoidal Pulse Width Modulation (SPWM) and space vector modulation (SVM) have been widely adopted for three-phase sine AC output from a fixed dc link if the dc link voltage is much higher than desired three-phase output. However, if the source/dc link voltage is lower than the load voltage, then frond-end dc/dc converters becomes necessary leading to the design of the multistage power conversion system. To implement existing SVM or carrier based modulation, traditionally a large costly unreliable electrolytic capacitor is employed to develop a high voltage intermediate dc link. Novel Single-reference-Six-Pulse Modulation (SRSPM) eliminates the dc link electrolytic capacitor allowing pulsating dc link voltage waveform at the inverter input. It substantially reduces the cost, size, and weight and improves reliability of the system. This novel SRSPM is simple and results in saving of 87% switching losses. The concept has been experimentally demonstrated with closed loop control to achieve 97% efficiency in lab. Co-sponsored by: IEEE Power Energy Society, Montreal Section Speaker(s): Akshay Kumar Rathore , MONTREAL, Quebec, Canada, Virtual: https://events.vtools.ieee.org/m/286365