Volt

Abstract: A high efficiency power supply for producing two regulated output voltages (i.e. 3.3 and 5 volts) from an unregulated input voltage. The supply includes a 4-15 volt battery pack, a first (5.0 volt) output, a second (3.3 volt) output, and a ground. The positive terminal of the battery is connected directly to the second output. The 3.3 volt differential with ground is maintained by a voltage regulator that couples the negative terminal of the battery pack to ground (i.e. ground floats relative to the battery). A second voltage regulator couples the positive terminal of the battery pack to the first output, and maintains this first output at 5.0 volts relative to ground. This latter regulator is capable of boost operation, permitting a 5.0 volt output to be maintained even if the battery pack voltage is less than this value. Neither regulator includes a transformer, making the supply particularly well suited for use in miniaturized equipment, such as palmtop computers.

Abstract: An implantable medical device, such as an implantable pulse generator (IPG) used with a spinal cord stimulation (SCS) system, includes a rechargeable lithium-ion battery having an anode electrode with a substrate made substantially from titanium. Such battery construction allows the rechargeable battery to be discharged down to zero volts without damage to the battery. The implantable medical device includes battery charging and protection circuitry that controls the charging of the battery so as to assure its reliable and safe operation. A multi-rate charge algorithm is employed that minimizes charging time while ensuring the battery cell is safely charged. Fast charging occurs at safer lower battery voltages (e.g., battery voltage above about 2.5 V), and slower charging occurs when the battery nears full charge higher battery voltages (e.g., above about 4.0 V). When potentially less-than-safe very low voltages are encountered (e.g., less than 2.5 V), then very slow (trickle) charging occurs to bring the battery voltage back up to the safer voltage levels where more rapid charging can safely occur. The battery charging and protection circuitry also continuously monitors the battery voltage and current. If the battery operates outside of a predetermined range of voltage or current, the battery protection circuitry disconnects the battery from the particular fault, i.e. charging circuitry or load circuits.

Abstract: As electric vehicle penetration grows, it is important to ensure that this new technology is deployed such that long-term efficiency and environmental benefits are maximized. In this study we examined the charging efficiency of Level 1 (120 Volt) and Level 2 (240 Volt) Electric Vehicle Supply Equipment (EVSE). Charging efficiency was defined as the percentage of power drawn from the electric grid that is actually taken up by the vehicle battery.

Abstract: A novel vehicle power supply system is suggested which receives its voltage supply from a starter/generator which can be used as a generator in normal operation and as a starter when starting, wherein the starter/generator is connected with a 24 volt ring mains as well as with a 24 volt battery via a pulse inverter and a 300 volt DC intermediate circuit and a bidirectional converter. Additional consumers can be supplied with higher voltages than 24 volts and electric control devices can be supplied with voltage, possible via additional converters, from the bidirectional push-pull converter and the 300 volt DC intermediate network. In addition, this vehicle power supply system contains a plug receptacle with a 220 volt 50 Hz voltage.