Abstract: An electronic device for effectively preventing time-varying current from passing through an electro-chemical cell or battery is disclosed. Time-varying current flowing in a circuit which includes the cell/battery is sensed externally to the cell/battery with a magnetically-coupled ac current probe thereby producing an induced time-varying signal. This induced signal is amplified to the level of the original time-varying current and applied to the cell/battery's terminals in phase-opposition to the original current. As a result, the component of time-varying current flowing in the cell/battery's external leads assumes an alternate path around the cell/battery and is effectively canceled within the cell/battery itself. Time-varying voltage across the cell/battery, which would normally result from time-varying current passing through its internal impedance, is likewise eliminated.
Abstract: In a method and a device for determining and indicating a residual capacity of a battery, a charging amount is measured in a charging mode in which a charger having a sensor for detecting a fully charged state is connected to the battery. If the charging amount in the charging mode is more than a trickle charging amount, the measured charging amount is added to a present charging amount to obtain the present charging amount and a ratio of the present charging amount to a fully charged state is indicated on a display unit. If the charging amount in the charging mode is less than a trickle charging amount, it is judged that the present charging amount is the fully charged amount and this amount is the fully charged state. The device further includes a current-to-voltage converting circuit, an analog-to-digital converter, and an operation control unit such as a MPU connected to the display unit and executing and controlling the operation of the device.
Abstract: A contactless recharging system and method for recharging a battery storage device onboard an electric vehicle has a primary converter station for converting power from a power source into high frequency power at a selected charging rate. The vehicle has a secondary converter for converting high frequency power into DC power to charge the battery. The converters are coupled together by a contactless coupling of a conductor loop and a coupling link forming a coaxial winding transformer. The coupled link and loop carry a communication indicating the selected charging rate of the battery. The link has a magnetic core and a core-mounted conductor at least partially surrounded by the core. The core-mounted conductor selectively at least partially surrounds a portion of the loop to transfer power therebetween. The core-mounted conductor is coupled to one of the converters, and the loop is coupled the other converter.
October 20, 1992
Date of Patent:
August 23, 1994
Electric Power Research Institute, Inc.
Keith W. Klontz, Deepakraj M. Divan, Donald W. Novotny, Robert D. Lorenz
Abstract: The electronic device powering system enables a battery powered device to power another device needing power while also powering itself. The accessory power connector (102) makes a connection before breaking it by a spring contact (110) that is more flexible in one end (111) than the other (112). This allows the less flexible end (112) to force the internal power connector (104) in the electronic device to break its connection.
Abstract: In the case of the multiphase switching system (1), each (for example L.sub.3) of the phase conductors is arranged in the course of a generator output line (2), which is arranged between a generator (7) and a network transformer (8), together with a switching apparatus, in encapsulation (5) which is insulated by air gaps, in a manner isolated from the other phase conductors.The switching system is intended to allow virtually all the switching, protection, and measurement functions occurring in a generator arrangement to be executed despite a compact and space-saving construction.This is achieved by the switching apparatus (three-position interrupter switch 10) having at least two switching positions. A first of these two switching positions is arranged between the generator (7) and an output of the switching system (1) which acts on the network transformer (8).
Abstract: An electric power system for an automotive vehicle is provided with a generator to which a 48-volt battery, a blower motor and a DC--DC converter are connected in parallel. An output terminal of the converter is connected to a load which is constituted by a 12-volt battery, a head lamp, a vehicle speed sensor and a resistance to which a switch is connected in series. The system is further provided with a voltmeter for detecting a voltage value of the 12-volt battery and an ammeter for detecting a load current applied to the load, a controller for controlling the converter and the switch. The controller controls the converter to start operation and the switch to be turned on when the voltage value detected by the volt-meter is lower than a first predetermined value and the load current detected by the ammeter is smaller that a second predetermined value. Accordingly, an operating period of the converter is shortened and therefore an energy loss generated in the system is suppressed.
Abstract: A device for use in conjunction with a battery in a motor vehicle which is connected to an electrical load. The device includes a microprocessor which iteratively inputs the value of the battery voltage as well as the ambient temperature surrounding the battery. The microprocessor also sets a cut off voltage level which increases proportionately with elapsed time from the last system reset of the device and preferably adjusts the cut off voltage level as a function of the ambient temperature of the battery. The cut off voltage level is set so that when the battery reaches the cut off voltage, sufficient energy remains in the battery for engine ignition, i.e. engine starting. The microprocessor then iteratively compares the battery voltage signal with the cut off voltage level and generates an output signal whenever the battery voltage is less than or equal to the cut off voltage level. The output signal initiates a timer which counts down a relatively short period of time, for example two minutes.
Abstract: A charger includes a control circuit (308) for determining the charge rate and charge capacity of a battery (312). Control circuit (308) switches the rate at which battery (312) is being charged from a first charge rate such as a rapid charge rate (206) to a charge rate which is increasing in charge over time (208). Once battery (312) becomes fully charged, control circuit (308) then charges battery (312) at a third charge rate such as a trickle rate (214).
Abstract: A method of regulating the charging of batteries containing a number of cells, for example NiCd cells. The battery is connected to a battery charger for impressing a current through the battery for charging thereof. Prior to the actual impression of current through the battery cells for raising their terminal voltage, the voltage drop caused by cables, connections, the inner resistances of the battery caused by the battery cells, etc., is established for a number of different brief current pulses. The value of the voltage drop established for each current pulse is stored in a memory, and currents of substantially the same magnitude as each respective current pulse are impressed successively through the battery, each one of a length of time such that the voltage measured across the battery corresponds to the maximum permitted terminal voltage of the battery, plus the voltage drop established and stored for the corresponding current pulse.
Abstract: A hand-held inductive charger having concentric windings for transferring electrical power across a dielectric medium using magnetic induction. The charger comprises a removable primary coil assembly having a housing with a primary core disposed therein, and a primary winding protruding from the primary core. An electrical cable coupled to the primary winding that is adapted to couple power thereto from a power source. A secondary coil assembly having a receptacle housing is also provided, and a secondary core is disposed in the receptacle housing, and first and second concentric secondary windings are disposed in the secondary core. The first and second concentric secondary windings are coupled to a battery of an automobile. The first and second concentric secondary windings have a gap therebetween that is adapted to receive the primary winding therein. The primary and secondary coil assemblies form a transformer when their respective windings are mated.
Abstract: A battery protection system for an engine-driven system having an engine, a storage battery to provide starting power for the engine, a main switch having a first condition in which the engine is operative and a second condition in which the engine is inoperative, and a load circuit connected to the battery to receive electrical power from the battery. The battery protection system protects the battery from being discharged below a predetermined minimum value sufficient to start the engine.
Abstract: A portable computer battery charger has a hollow housing which is supportable on a generally horizontal surface and has a power wiring board horizontally disposed within a bottom portion thereof beneath a depending pair of vertically tilted, open-topped wells formed in the top wall of the housing. The power wiring board is adapted to receive electrical charging energy from a source thereof, and has a plurality of resilient metal clip members electrically connected thereto and projecting upwardly through bottom end openings in the wells. To charge a pair of elongated portable computer batteries charging ends thereof are placed in the wells which support the batteries in a vertically tilted orientation in which major longitudinal portions of the batteries project upwardly beyond the top side of the housing.
Abstract: When an AC adapter and a battery are connected to a system, trickle charge is performed with respect to the battery through a trickle charge resistor. During the trickle charging of the battery, the adapter voltage of the AC adapter and the battery voltage of the battery are detected by voltage detectors, respectively. On the basis of a differential voltage representing a difference between the two detected voltages, a power source controller controls the start and stop of the trickle charge at predetermined timings in such a manner that a trickle charge current does not exceed a predetermined value even when the differential voltage increases.
Abstract: The problems of minimizing size and weight in an aircraft and avoiding requirements for custom design are minimized in a generator control unit (22) provided with separate digital control circuits (74 and 76) for implementing voltage regulation and speed control. These circuits (74 and 76) are manufactured using custom very large scale integration (VLSI) technology to reduce size, weight, life cycle costs and improve reliability.
Abstract: A regulator circuit for regulating the voltage delivered by an alternator for charging an associated battery, the alternator including an excitation winding and the regulator circuit controlling the current flowing through said excitation winding by switching between a first state in which excitation current increases and a second state in which excitation current decreases, said current being controlled as a function of a voltage value delivered by said alternator, wherein the circuit comprises:(a) detection means for determining whether the time during which the regulator circuit is in its first state is greater than a threshold time;(b) means for generating a speed signal representative of the speed of rotation of the alternator;(c) means responsive to a signal provided by the detection means to periodically compare said speed signal with a predetermined relationship establishing admissible decrease in the speed of rotation of the alternator as a function of time; and(d) means for temporarily switching sai
Abstract: A weatherized curb-side battery charging system that provides a mechanism for transferring electrical power to an electric vehicle to recharge its battery. The battery charging system includes a housing that is disposed on a wall or is slidably attached to a track mounted to a ceiling, for example A retractable charging device is coupled to a power supply and mates with a receptacle device disposed in the vehicle. A variety of charging devices that may be employed in the battery charging system are disclosed. Electronic circuitry controls power supplied to the vehicle from the power supply of the charging system. In addition, an interface circuit is provided that allows a user to enter a code to use the system and that provides an identification for billing purposes, or a credit card type key that activates the system and performs the same functions. A fan is provided for cooling purposes that causes an air flow through the system.
January 22, 1992
Date of Patent:
June 21, 1994
Hughes Aircraft Company
Michael F. Bruni, Gerald A. Cox, Mark Biasotti
Abstract: A power supply device including a switching regulator, to supply electric power from a battery to a device to be operated, such as a motor. A first switch is provided between the battery and the switching regulator. A second switch is provided between the switching regulator and the device to be operated. A voltage sensing circuit is provided for sensing an output voltage of the battery. When the battery voltage is higher than a predetermined value, the first and second switches are switched so that the battery voltage is applied on the motor through the switching regulator. When the battery voltage is lower than a predetermined value, the first and second switches are switched, so that the battery voltage is applied on the motor without the switching regulator.
Abstract: A battery charger device is provided with a control switch which connects electrically a rechargeable battery load to a power supply which supplies charging current for charging the battery load. A pulse generator generates a series of pulses that control the control switch to connect and disconnect intermittently the power supply and the battery load. A maximum battery terminal voltage of the battery load is stored in a voltage memory means, and a fractional voltage is derived from the maximum battery terminal voltage. The fractional voltage is compared with a current battery terminal voltage from the battery load. A control signal is generated so as to prevent the control switch from receiving the pulses from the pulse generator, thereby disconnecting the power supply from the battery load so as to terminate charging of the battery load when the current battery terminal voltage is less than the fractional voltage.
Abstract: A current limited, voltage regulated, battery maintainer and charger apparatus includes a circuit for monitoring and maintaining a 12 volt storage battery, determining the presence of forward polarity and in response controlling the amount of charging current necessary to continuously maintain the battery in a ready state, without overcharging or causing other damage to said battery. The battery maintainer device selectively charges 12 volt lead acid, gel-cell or sealed lead acid batterys using current limitation and voltage regulation circuitry, to modulate an amount of current to maintain a voltage potential across the battery, whereby the current flow can drop to zero current flow, to maintain a constant and continuous storage battery voltage of 13.8 volts.
Abstract: A charging control apparatus for a vehicle, which controls a power generation of an AC generator for charging a battery, comprises: a switching circuit connected in series to a field winding of the generator; a comparator for detecting a voltage of a battery and comparing the battery voltage with a sawtooth wave of a predetermined period; a memory device for storing a value regarding a duty factor of an output of the comparator at the same period as the predetermined period of the sawtooth; a control value increasing/decreasing circuit for increasing or decreasing a control value as an output, thereby making the stored value coincide with the control value; and an AND circuit to calculate AND of the control value and an output of the comparator.