Resumo:
The present work aims to present a new topology of direct AC-AC converter to switched capacitor. This topology employs only semiconductor elements and capacitors, presenting itself as an alternative to low voltage autotransformers with reduced cost and size. This new structure can operate as a voltage step-up or step-down, with a gain of up to 3 or even 1/3, providing 3 different output voltage levels. Initially, the context of the use of autotransformers is shown for different applications. Direct AC-AC conversion structures are presented, from those that operate at low frequencies using controlled rectifiers, to those driven by PWM that employ high-speed switches. Among the latter, the switched capacitor converters stand out due to their constructive simplicity and performance. In this work, the proposed new topology and its operation steps are presented. Mathematical expressions are developed to calculate the elements that make up the converter. Finally, a circuit is designed, simulated and tested on the bench so that its calculations and operation can be validated. The results in terms of regulation and yield are presented so that it can be seen that this new structure can replace an autotransformer in certain situations. At the end of the text, a proposal for the continuity of the work for the conclusion of the thesis is presented.
