Performance Evaluation of a Synchronous DC-DC Boost Converter with Adjustable Output Current

Abstract

The research aims to implement a 450Watts synchronous DC-DC boost converter with an adjustable output current operation. A unit was built and tested. The power supply unit (PSU) was designed for battery charging applications and designed to perform in continuous conduction mode and to operate at two modes: constant-voltage (CV) and constant-current (CC). Initially the PSU was operating at CV Mode. Once the PSU reached the current limit, power supply operates at constant current mode, the power supply acts as a current source with varying output voltage depending on the value of the load resistance. The PSU uses the inherent fault protections of main controller such as cycle-by-cycle current limiting, inrush current limiting, hiccup mode short circuit/overload protection, and the researchers implement over-voltage protection (OVP), over-temperature protection (OTP), and reverse polarity protection (RPP) by using additional comparator circuitry. The results presented in this study show that the design is has a regulated output voltage of 53.9V with maximum of 236mV peak-to-peak voltage ripple and 120mA peak-to-peak current ripple which was measured at full load condition. Through the constant voltage test, the unit can maintain a constant output current from 2A up to 8A by adjusting the potentiometer. The 96% efficiency was achieved at 3A load from an input voltage range of 11.34V to 13.86V.