William A. Peterson

An EV on-board battery charger

A battery charger for electric vehicles (EV) is described. This charger is designed to provide the minimum recharge time by completely utilizing the available power sources. Charging rates up to 10 kW are supported. The required external infrastructure is also minimized so that charging may safely occur without specialized equipment. The power sources utilized are as flexible as possible to permit charging at as many places as possible. Additionally a DC power source, such as another EV, can be used as the power source permitting safe energy transfer between vehicles. The charging circuitry is lightweight and small, 37 pounds and 720 cubic inches, since the charger is on board the vehicle. Efficiency has been optimized, to reduce the need for heavy heat sinks and to maximize the energy available for charging. A microprocessor controls the charging process and tracks state of charge for several battery electrochemistries.

Design techniques for very wide input range power converters

One of the primary functions of any power supply is to provide a constant or regulated output from an input source that is not constant. The variations in the level of input that must be accommodated will have an impact on the circuit type that is used and the performance that will be achieved. As the range of input voltage that must be accommodated increases, the stress on critical components also increases. Therefore, it is prudent to limit the input dynamic range as much as possible. There are special instances where it is not possible to limit the input dynamic range. In such cases, a power supply with increased size and/or reduced performance must be accepted.