A power converter nearly losslessly delivers energy and recovers energy from capacitors associated with controlled rectifiers in a secondary winding circuit, each controlled rectifier having a parallel uncontrolled rectifier. First and second primary switches in series with first and second primary windings, respectively, are turned on for a fixed duty cycle, each for approximately one half of the switching cycle. Switched transition times are short relative to the on-state and off-state times of the controlled rectifiers. The control inputs to the controlled rectifiers are cross-coupled from opposite secondary transformer windings.

High efficiency power converter

An AC adapter that allows a lower power rating while still providing the necessary power to a load which is substantially constant over a varying voltage range and to charge a discharged Ni-Cad battery in a desired time. The AC adapter regulates its output power to a maximum level just greater than the maximum of the load rather than providing a controlled current until a predetermined fully charged voltage is attained. In this manner, the output voltage and current are allowed to vary inversely with respect to each other in order to maintain the desired power level, allowing the output current level to be reduced as the voltage level increases. A regulated voltage mode is also provided to keep the output voltage from rising above a predetermined maximum level should the Ni-Cad battery be disconnected. One preferred embodiment includes a regulated current mode wherein the current through the Ni-Cad battery is maintained at the desired trickle level once the battery is fully charged.

Maximum power regulated battery charger

Systems and mehtods for producing standby uninterruptible power for an AC load rectify an AC utility input voltage to produce a rectified voltage and activate a DC battery voltage in response to a change in the AC utility input voltage to thereby produce a standby DC voltage. The rectified voltage and the standby DC voltage are connected to an AC load that includes input rectification to thereby produce standby uninterruptible power without the need for costly, bulky, and/or unreliable inverters or converters. Seamless transfer of power may be provided to support the AC load upon failure of the AC utility input voltage and upon restoration of the AC utility input voltage. The AC utility input voltage is preferably rectified by a diode rectifier, most preferably a full-wave diode rectifier including at least four diodes, to produce the rectified voltage. A diode switch is used to activate the DC voltage from the battery in response to a change in the AC utility input voltage to thereby produce the standby DC voltage. The diode switch may include a separate diode and an electronic or electromechanical switch. Alternatively, the diode switch may be a single element such as a thyristor. The diode rectifier and the diode and switch are connected in a diode-OR connection that provides the standby uninterruptible power for the output of the UPS. The diode-OR connection allows the strongest source to support the AC load at all times.

Systems and methods for producing standby uninterruptible power for AC loads using rectified AC and battery

A battery charger having an input receptacle, and different AC electrical cords pluggable therein for adapting the charger to a variety of different AC distribution systems. Portions of rectified signals are coupled by a triggerable switching device to a battery to be charged. The switching device is triggered only on a negative slope portion of the rectified signal, at a specified rectified signal amplitude, only when a battery is connected to the charger, and when the battery indeed requires charging.

Universal battery charger

An emergency lighting fixture, for plug-in installation in a wall connector mounted protruding from a fixed wall plate, has a back plate secured to its wall-engaging face. The back plate and the wall plate are provided with interfitting flanges and a pivoted latch secures the plates together in facing juxtaposed engagement. A mating multi-prong plug and socket connects A.C. line power from the wall connector to internal circuitry in the lighting fixture for lighting a lamp, for charging a rechargeable internal battery and for operating a transfer circuit to deliver battery power in the event of line power failure. The conductor from one terminal of the battery is connected to said circuitry by two prong-and-socket pairs, in the multi-prong plug and socket, which are connected by a permanent jumper conductor in the wall connector, affording battery isolation in the lighting fixture until its plug-in installation in the wall connector is completed.

Connector assembly for plug-in energization and battery activation of an associated electrical apparatus

A voltage-regulated power supply with standby power capability particularly adapted for use in data-processing equipment and the like is shown to comprise a sealed, rechargeable battery to be connected across a load for determining load voltage and for cooperating in meeting current demands of the load, a direct current energy source arranged to provide charging current to the battery and to cooperate in meeting the current demands of the load, and control means regulating the charge state of the battery for maintaining load voltage within selected limits

Bertrand J Misek

Papers

Voltage-regulated power supply with standby power capability