| Future computer and telecommunication power distribution systems require the power source to be high frequency ac type and be combined with line current Power Factor Correction that satisfies IEC 1000-3-2 standard. In addition, low power applications require high efficiency, high power density and cost effectiveness. This thesis provides a solution to low power ac-ac inverter for the future computer and telecommunication power distribution systems, which complies with the above requirements.; The proposed high frequency ac-ac inverter operates under Zero Voltage Switching (ZVS) throughout the whole range of the line voltage and load. Hence, high efficiency can be realized under high switching frequency. A unified controller is introduced in the proposed ac-ac inverter to control the dc-ac stage and the PFC stage at the same time. The controller is simple and the DC bus voltage can be well limited for A line and load conditions. Hence, cost effectiveness can be realized.; In the thesis, two types of PFC stage converters (Boost and Buckboost) are presented to compare the performance of the ac-ac inverter. Principle of operation and steady state analysis of the proposed topology are given. Performance characteristics, design procedures and computer simulation results are presented to guide the design. Experimental results from a prototype of 100kHz, 30Vac/250W output, 90–265Vac input, are presented to confirm the analysis and performance of the proposed ac-ac inverter. |
