shows the curves of system PF, THD, and efficiency
with changing loads. A power-quality analyzer was used
to measure the system efficiency, including the losses in the
EMI filter. The system PF is always higher than 0.99, THD
remains lower than 10%, and the system efficiency is greater
than 89.5%, when the load changes from 50% to 100%. It is
also noticed that the efficiency is as high as 90.8% at steady
state.