Enerji Dönüştürücüler için Ara Devresi

Abstract

This paper presents an efficient self-startup interface circuit for ambient energy sources. The proposed circuit consists of a charge pump, a boost converter, a charge transfer control circuit and some passive components. The charge pump boosts the low voltage at the output of the energy source to store the charge into a super capacitor. Once enough charge is stored into the super capacitor, the charge transfer control circuit has been active (i.e. being on) to bridge the super capacitor to the boost converter. Thus, the load receives power supply in a short period of time i.e., operates in the burst mode since the generated power at the energy source is lower than the power required by the load. The boost converter is used for providing a constant voltage level (e.g. 3.3 V) to the load. The proposed circuit has been evaluated using off-the-shelf components and connects to emulate the energy source. A voltage source in series with a resistor can be modeled to emulate the energy source. The proposed circuit can start the operation as low as 0.3 V input voltage and up-convert to 3.3 V. The proposed interface circuit has been tested for various loads in order to indicate the effectiveness of the circuit. The proposed circuit has a peak overall efficiency of 11.56 %, which is higher than the conventional interface circuit achieves. As compared to conventional interface circuit, the proposed circuit enhances the efficiency by 1.8 X. The measured results indicate that the proposed circuit achieves a high efficiency without the need of external supply.