Synthesis ofImpedanceUsingSwitching Converters

A general impedancesynthesizer using a minimum numberofswitching converters isstud- iedinthispaper.We beginwithshowingthatany impedancecanbe synthesized by a circuit consist- ingofonlytwo simplepowerconverters, one stor- age element(e.g., capacitor), and one dissipative element(e.g., resistor) or power source.The im- plementation ofsucha circuit forsynthesizing any desired impedancecanbeperformedby(i)program- mingtheinputcurrentgiventheinputvoltagesuch thatthedesiredimpedancefunction isachieved; (ii) controlling theamount ofpowerdissipation (gener- ation)inthedissipative element(source) soasto matchtherequiredactivepoweroftheimpedance tobe synthesized. Then,theinstantaneous power willautomatically be balancedby thestorageele- ment.Suchimpedancesynthesizers finda lotofap- plications inpowerelectronics. Forinstance, aresis- tancesynthesizer canbeusedforpowerfactor cor- rection(PFC),a programmablecapacitor orinduc- torsynthesizer (comprising ofsmallhigh-frequency converters) canbeusedforcontrol applications.