Improved modulation technique for voltage fed quasi-Z-source DC/DC converter

A new shoot-through pulse width modulation (PWM) technique for voltage fed quasi-Z-source DC/DC converters is presented. One advantage of the technique is it minimizes switching losses in the converter by minimizing the number of switching commutations of the active devices in the intermediate H-bridge. The duration of the active and shoot-through states are independently controllable, allowing the shoot-through duty cycle to reach its maximum limit (D st, max = 0.5), thus enabling a high voltage gain suitable for applications with renewable energy sources (fuel cells, photovoltaics) and other applications requiring a large voltage boost. In addition, the switches achieve zero voltage switching (ZVS) which reduce EMI and improves efficiency of the converter. A 500W prototype converter was implemented demonstrating improved performance with the new modulation technique.6 page(s