A circuit and method for controlling a switching voltage regulator having (1) a switch including one or more switching transistors and (2) an output adapted to supply current at a regulated voltage to a load including an output capacitor. The circuit and method generates a control signal to turn said one or more switching transistors OFF under operating conditions when the voltage at the output is capable of being maintained substantially at the regulated voltage by the charge on the output capacitor. Such a circuit and method increases the efficiency of the regulator circuit particularly at low average current levels.

Control circuit and method for maintaining high efficiency over broad current ranges in a switching regulator circuit

Power supply systems and methods are provided. In one aspect, a power supply system includes a frame, a power input to receive input power from a power source, a power output to provide output power to a load, at least one battery module mounted in the frame and having a battery output that provides battery power, at least one power module mounted in the frame and coupled to the power input to receive the input power, coupled to the battery output to receive the battery power, and coupled to the power output to provide the output power from at least one of the battery power and the input power, a first controller coupled to the at least one power module, and a second controller, substantially similar to the first controller, coupled to the first controller, and coupled to the at least one power module, wherein each of the first controller and the second controller are configured to determine operational parameters of the power supply system and store a first set of parameters determined by the first controller and a second set of parameters determined by the second controller.

Method and apparatus for providing uninterruptible power

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Distributed Power Harvesting Systems Using DC Power Sources

A light emitting diode (LED) lighting system includes a PFC and output voltage controller and a LED lighting power system. The controller advantageously operates from an auxiliary voltage less than a link voltage generated by the LED lighting power system. The common reference voltage allows all the components of lighting system to work together. A power factor correction switch and an LED drive current switch are coupled to the common reference node and have control node-to-common node, absolute voltage that allows the controller to control the conductivity of the switches. The LED lighting system can utilize feed forward control to concurrently modify power demand by the LED lighting power system and power demand of one or more LEDs. The LED lighting system can utilize a common current sense device to provide a common feedback signal to the controller representing current in at least two of the LEDs.

Power control system for current regulated light sources

A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes corresponding to different levels of input voltage or output current. The power converter comprises a power stage for delivering the electrical power from the power source to the load, a switch in the power stage that electrically couples or decouples the load to the power source, and a switch controller coupled to the switch for controlling the on-times and off-times of the switch according to the plurality of operation modes. Each of the operation modes correspond to associated ranges of at least one of an input voltage to the power converter and an output current from the power converter, where the associated ranges are different for each of the operation modes.

System and method for input current shaping in a power converter

An off-line switching power supply is described which controls the switching transistor of a fly-back circuit in such a fashion as to achieve better than 0.99 power factor control. The technique used for power factor control allows the switching power supply to operate either from AC or DC sources. The power supply operating from an AC source will accept all international voltages and line frequencies as input to produce a well-regulated DC output. The inductor of the fly-back circuit is maintained at the verge of continuous/discontinuous operation by the power factor control circuit to achieve a high efficiency operation and to minimize switching losses. The power factor correction circuit uses pulsewidth modulation and frequency modulation to control the switching transistor and maintain a high power factor under varying line and load conditions. The power supply also includes integral current limiting protection and RFI filtering for safe and quiet operation.

D. Bucher Ii James

Papers

Switching power supply with automatic power factor correction