Hybrid Modulation Scheme for a High-Frequency AC-Link Inverter

 Hybrid Modulation Scheme for a High-Frequency AC-Link Inverter

 A hybrid modulation scheme for a high-frequency ac-link (HFACL) multistage inverter comprising a front-end dc/ac converter, followed by isolation transformers, an ac/pulsating-dc converter, and a pulsating-dc/ac converter. The hybrid modulation scheme enables 1) removal of the dc-link filter evident in conventional fixed dc-link (FDCL) inverters placed after the ac/pulsating-dc converter stage and before an end stage voltage source inverter and 2) significant reduction in switching loss of the inverter by reducing the high-frequency switching requirement of the pulsating-dc/ac converter by two-third yielding higher efficiency, improved voltage utilization, and reduced current stress.