Derivation, Analysis, and Comparison of Nonisolated Single-Switch High Step-up Converters with Low Voltage Stress
This project presents nonisolated single-switch high step-up converters with low voltage stress. Based on the conventional flyback converter, one single-switch high step-up converter is derived. The voltage stresses on the switch and diodes are limited by using a clamping diode and voltage doubler structure. Also, to further reduce the voltage stresses of them, another single-switch high step-up converter is proposed simply by using one additional capacitor and rearranging the components. Thus, lower voltage rated switch and diodes can be used, which results in higher efficiency.
The converters adopting the transformer, such as flyback, forward, push–pull, half-bridge, and full-bridge types, can be used to obtain high voltage gain by adjusting the turns ratio of the transformer. Among them, the flyback converter is very widely used in low power applications due to the simple structure which results from single switch, diode, and transformer. However, the primary switch and secondary diode suffer from high voltage stress due to the leakage inductance of the transformer. This limits the use of flyback converter for higher power application.
Nonisolated single-switch high step-up converters with low voltage stress are presented. The derivation and analysis are illustrated in this paper. The validity of the basic operational principle is verified by the experiment with 24/12 V input output prototype. The proposed converter features that the switch and diodes have the lowvoltage stress, so the lowvoltage- rated devices is used. From the experimental results, the proposed converter shows higher efficiency under entire load conditions due to the low conduction loss.
TOOLS AND SOFTWARE USED:
- MP LAB
Jae-Kuk Kim and Gun-Woo Moon, “Derivation, Analysis, and Comparison of Nonisolated Single-Switch High Step-up Converters With Low Voltage Stress”, IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 30, NO. 3, MARCH 2015.