Battery vehicle charger design eliminates harmonic current generation

A 150 kilowatt rapid battery charger has been designed for providing battery vehicles a midday booster charge or opportunity charging at an automotive type service station to extend the range. The charger is universal in concept, meaning that is can charge any battery type, any battery pack voltage (up to 325 V), and can be programmed to implement any charge algorithm. It was specifically designed to be "neighhor friendly" by not producing harmonics, and not causing fluctuations in line voltage even when operating in a pulse charging mode. A prototype, of this charger design, for charging a single six volt golf cart battery has been designed, built, and tested for the purpose of implementing and verifying the performance of various fast charging algorithms without the risk of damaging an entire vehicle battery pack. The completed prototype has exceeded all design goals and it has been used to test various fast charge algorithms. All of the power electronics were built for the full element of 650 A/sub DC/ and the semiconductors all have 600 volt ratings. The transition from this prototype to a full scale version will require only a higher voltage rotating field input transformer and rectifier.