Note that the two othe ractive swiutches operate with Yeroi Voltage Switching (ZVS) thus elimnating those switching losses. This hybrid transformer implementation is even closer approximation than transformer in isolated Ćuk converter to the ideal transformer of the Faraday type. This is why this converter is very first which eliminates completely losses due to energy normally stored in leakeage inductance of the transformer. The green waveform of the primary current is purely sinusouidal AC current with ZERO DC (average current) without any jumps in primary current waveform. Introduction to Ćuk-buck 2 converter: The Ćuk-buck2 converter needs only one module and settles the transient in a fraction of a single switching cycle of 10 microseconds or 100kHz constant switching frequency in direct single-stage 48V to 1V conversion while at the same time eliminating Intermediate Bus Converter (IBC) (48V to 12V intermediate stage!) with its extra losses, size and cost penalties! No present single converter or one using multiple stages of conversion to provide 48V to 1V conversion is even contemplating to handle step-looad current transient performance required by microprocessors! This is perfectly demonstarted by GOOGLE's APEC 2017 presentation enclosed below listing some dozen configurations, each with 12 or 20 switches each (!) and still not even attempting to address transient load requirements! Ćuk-buck 2 displayed below achieves that with 3 switches only and a unique new magnetics component I call hybrid transformer! The conversion gain is DN2/(N1+N2) with regulation provided by duty ratio D modulation, independent of either Resonant inductor Lr or Resonant capacitor Cr or even of any load current change from full load to no load! This is made possible by unique feature that the diode current (orange color) in simulations is ALWAS POSITIVE and turning ON at zero current and turning OFF at zero current (ZVZS switching) for ANY load, resulting in elimination of diode switching losses for all operating conditions. This is now managed by a clearly brute-force approach of up to 12 synchronous buck converters in parallel providing 12V to 1V, 100A conversion at 5MHz switching frequency with efficencies below 90%. Voltage Regulator Modules for MicroprocessorsĪt present all microprocessors require special power supply which can handle large 80% step-load current change in extremely short time on the level of 50A/microseconds with minimal voltage overshoot.
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