Abstract

This project consists of a LLC resonant converter with its features enhanced by including a resonant tank circuit design which reduces the harmonics considerably. By using this LLC Multi Resonant DC to DC Converter, we are able to reduce the harmonics and ripple frequency in a NEV battery charging system.By using this specific converter design, the battery charger can respond to the condition of a battery, and modify its charging actions according to the battery algorithm. Thus much more desirable output voltage can be achieved and due to this the Battery is able to charge faster and have a longer life cycle than when it is charged by other type of chargers.The Multi Resonant Converter has been analyzed and its performance characteristics are presented. It eliminates both low- and high frequency current ripple on the battery, thus maximizing battery life without penalizing the volume of the charger.This prototype unit converts 390V from the input dc link to an output voltage range of (48–72)V dc at 650 W. The prototype achieves a peak efficiency of 96%.

Key words: LLC Multi Resonant; NEV battery; harmonics