1680 results about "Current sharing" patented technology

A new system-level approach to managing the delivery of DC voltage and current. Several system level functions may be enabled without requiring separate ICs to perform those functions. Supervisory functions for a voltage converter may be performed by a central control module or chip that may be coupled to point-of-load voltage converters comprised in digital power management devices (DPMD) through a serial digital bus. The DPMDs may also use the high-speed serial digital bus to provide real-time feedback information to the central control module or chip. Single DPMDs may be combined together in a current sharing configuration in a “plug-and-play” fashion, where the control logic in each DPMD is capable of automatically establishing control loops required a multi-phase supply. Feedback necessary for establishing control may be transmitted across the digital bus coupling the devices. The supervisory functions may be included in each DPMD, which may communicate with each other over a serial digital bus, where the DPMDs singly or together may operate to perform control of their respective POLs, enabling configurations that do not require a central control module.

A ripple-mode controller provides reliable operation in multi-phase power supply circuits, over a variety of operating conditions. Cross-phase blanking allows the controller to preserve the desired phase relationship between the switching pulses its provides to the different output phases, and permits the controller to operate each output phase at nearly 100% duty cycles. Active current sharing compliments blanking operations by adjusting the width of switching pulses the controller provides to one or more of the output phases based on detecting load current imbalances between the different output phases. With active current sharing, the controller prevents one or more output phases from carrying excessive portions of the load current. Further complimenting its operation, the controller may include virtual ripple generation to increase the noise immunity of its ripple-mode regulation.

A ring balancer comprising a plurality of balancing transformers facilitates current sharing in a multi-lamp backlight system. The balancing transformers have respective primary windings separately coupled in series with designated lamps and have respective secondary windings coupled together in a closed loop. The secondary windings conduct a common current and the respective primary windings conduct proportional currents to balance currents among the lamps. The ring balancer facilitates automatic lamp striking and the lamps can be advantageously driven by a common voltage source.

An LED driver includes at least two interlocked closed feedback loops. One feedback loop controls the duty cycle of the on / off times of a switch connected in series to the LED string, and the other feedback loop controls the duty cycle of the on / off times of a power switch in the switching power converter that provides a DC voltage applied to the LED string. The LED driver of the present invention achieves fast control of the LED brightness and current sharing among multiple LED strings simultaneously in a power-efficient and cost-efficient manner.

A power redundant power system and a method for controlling the power system are presented, wherein the power system is composed of at least one inverter for supplying AC power to a load through a bus, a phase lock system to synchronize all output voltages of the inverters and a current sharing circuit to properly distribute the load current among all inverters. Each inverter is controlled by an unbalanced power to limit the increase of its cross current. Moreover, the information related to DC bus voltage is further applied to control the inverters, whereby the cross current is mitigated and entire power system is operated steadily.

The invention discloses a PFC circuit which is provided with an average current control module, comprising a first boosting circuit, a second boosting circuit and the average current control module. The average current control module comprises a sampling unit, a difference value operating unit, a proportion integral unit and a duty ratio regulating unit which are connected one by one. The duty ratio regulating unit realizes the average current of the inductance current mean in a switch cycle. The invention also discloses an average current control method used for the PFC circuit, and the method comprises the following steps: A. a reference current is produced; B. the current is sampled and the difference value is operated to obtain the inductance current difference value of two parallel branches; C. control signal one of the first boosting circuit is produced through operation; D. control signal two of the second boosting circuit is produced through operation; E. the duty ratio of the two branches is obtained by regulating the duty ratio.

The various embodiments and example provided herein are generally directed to novel multiphase resonant converters. In an embodiment, a multiphase resonant converter comprises N unit resonant converters having inputs and outputs connected in parallel, respectively. Each unit converter comprises an inverter, a LLC series resonant tank, and a rectifier. In a preferred embodiment, the inverters of the N unit converters are driven by N drive signals phase-shifted 2π / N degrees apart. During operation, the current of the multiphase converter is shared among the unit converters, resulting in a smaller current in each unit converter. The smaller current in each unit converter reduces conduction losses, thereby increasing the efficiency of the multiphase converter. In addition, the smaller current in each unit converter reduces the amount of stress placed on individual components of the converter allowing for the use of lower tolerance components. Further, the multiphase converter has automatic current sharing ability.

A converter module for use as a phase in a multiphase DC-DC converter having a data bus for transferring current-sharing information is provided. The converter module comprises a power stage and a controller. The power stage comprises an input for receiving an input voltage and an output for providing an output voltage and an output current. The controller is coupled to the power stage to receive a feedback signal from the power stage. The controller further comprises a data bus port configured to receive the current-sharing information from the data bus and provide updated current-sharing information to the data bus. The controller is also configured to: (1) determine a current level being provided by said power stage, (2) update the current-sharing information based upon the determined current level, (3) determine a current error based upon the determined current level and the updated current-sharing information, (4) control an operation of said power stage based upon the current error, and (5) provide the updated current-sharing information to the data bus. In another embodiment, a multiphase DC-DC power converter comprising a first phase, a second phase, and a data bus is provided. In yet another embodiment, a method of sharing current information between phases of a multiphase DC-DC converter is provided.

The battery charger is modular and reconfigurable. It includes charging modular power stages that are configured to receive an alternating current (AC) input and provide a direct current (DC) output for charging a battery. These modular power stages include an inverter coupled to a rectifier circuit that outputs a battery charging current. The modular power stages can also each include a current mode controller coupled to the output of the rectifier circuit and configured to provide a current control signal for the modular power stage, a voltage mode controller coupled to the output of the rectifier circuit and configured to provide a voltage control signal for the modular power stage, and a droop sharing control and configured to ensure current sharing between a plurality of modular power stages under constant voltage operation. A system controller is configured to interface with the modular power stages.

Cutout and / or keep away regions are etched in the winding structure near the gapped center leg of a magnetic core. This reduces eddy current losses caused by the leakage field and improves current uniformity and current sharing between windings thereby increasing converter efficiency. Windings closest to the air gap are suitably formed with both keep away regions and cutouts. Windings a little further away are formed with only cutouts and the windings furthest away are unchanged. This approach keeps the net winding losses low in the presence of a fringing field. The precise configuration is determined by the core structure, air gap and winding arrangements.

A parallel redundant power system and a method for control the same, wherein the power system is composed by UPS modules with outputs coupled in parallel to supply power to a load through a bus. The control method employs the P-omega and Q-V slope lines of the droop method to perform phase locking and current sharing. Moreover, the method further utilizes the internal impedance of the UPS in accompaniment with a current shift method to simulate an actual inductor being coupled to the output of the UPS module so as to satisfy the droop method. Therefore, the drawbacks otherwise caused from actual inductors such as the large size and heave weight are eliminated.

A parallel DC-to-AC power inverter system is provided. The parallel DC-to-AC power inverter system has a first DC-to-AC power inverter electrically connected in parallel with a second DC-to-AC power inverter, and each of the DC-to-AC power inverters includes an input port, an output port, a switching circuit electrically connected between the input port and the output port responsive to inverter control signals to convert a DC voltage at the input port to a first AC output voltage, an inductor-capacitor filter electrically connected to the switching circuit for filtering the first AC output voltage to an AC output voltage at output port, and a controller module for detecting an inductor current at the inductor-capacitor filter to generate an AC inductor current signal, for detecting the AC output voltage at the output terminals and transforming the AC output voltage to generate a first AC reference current signal, for detecting a load current at output port to generate an AC load current signal, for generating a second AC reference current signal by adding the first AC reference current signal to the AC load current signal, for performing a numerical operation of the second AC reference current signal of the first DC-to-AC power inverter and the second AC reference current signal of the second DC-to-AC power inverter to generate an AC reference current signal, and for generating the inverter control signals responsive to the AC reference current signal and the AC inductor current signal by sensing the inductor current at the inductor-capacitor filter. The related methods are also discussed.

Disclosed is a digital current sharing structure and method in which a plurality of regulators are configured to share the load current. Current share circuits in each of the regulators are configured to measure and compare the average current provided by that particular regulator with the overall average current provided by all the regulators. Each of the current share circuits then provides an output so that the output of each regulator is adjusted to provide the same amount of current to the load. Digital processing with both analog and digital averaging are disclosed. Also disclosed is a programmable hysteresis technique to eliminate relatively trivial adjustments.

The invention discloses a parallel structure and a control method for a photovoltaic power generation grid-connected inverter and belongs to the technical field of renewable energy sources. A topological circuit structure of the photovoltaic power generation grid-connected inverter is divided into a parallel structure of single-phase voltage type pulse-width modulation (PWM) inverters and a parallel structure of three-phase voltage type PWM inverters; and in the control method, an outer ring regulator of a control circuit of the parallel voltage type PWM inverters is independent based on a power grid voltage-oriented vector control technology in a control mode of voltage outer ring and current inner ring so as to form a common unified outer ring regulator; control strategies of various inverters are simplified into single closed loop current control so as to achieve the consistency of energy flow directions of the parallel voltage type PWM inverters and avoid ring current; and the parallel current sharing of the voltage type PWM inverters is realized. Therefore, multiple modules of the voltage type PWM inverters are connected in parallel to realize high-power modularized large-scale application.

A multi-phase power block for a switching regulator includes a phase control circuit, N power cells and a current sharing control circuit. The phase control circuit is configured to receive a single phase PWM clock signal and generate N clock signals in N phases. Each of the N power cells includes a pair of power switches, gate drivers, a control circuit receiving one of the N clock signals and generating gate drive signals for the gate drivers, and an inductor. The current sharing control circuit is configured to assess the inductor current at the inductor of the N power cells and to generate duty cycle control signals for the N power cells. The duty cycle control signals are applied to the control circuits to adjust the duty cycle of one or more clock signals supplied to the power cells to balance a current loading among the N power cells.

A ring balancer comprising a plurality of balancing transformers facilitates current sharing in a multi-lamp backlight system. The balancing transformers have respective primary windings separately coupled in series with designated lamps and have respective secondary windings coupled together in a closed loop. The secondary windings conduct a common current and the respective primary windings conduct proportional currents to balance currents among the lamps. The ring balancer facilitates automatic lamp striking and the lamps can be advantageously driven by a common voltage source.

The provided method and control circuit are employed to alternately control the dual boost PFC circuits. The control circuit for alternately controlling parallel-connected first and second boost circuits of a dual boost PFC circuit to achieve a current-sharing of the first and the second boost circuits includes: a first control circuit having a first current control loop for employing an output voltage of the PFC circuit, a feed-forward voltage, and an input reference voltage to generate a current reference, and sending the current reference to an input terminal of the first current control loop to generate a first PWM signal to drive the first boost circuit, and a second control circuit having a second current control loop for receiving the current reference through an input terminal of the second current control loop to generate a second PWM signal to drive the second boost circuit.

A pulse width modulator (305) for driving a load in a multi-phased power system having circuitry (270) responsive to channel signals for providing an average signal by summing the channel signals at a node (221) which is coupled with a plurality of resistive elements, and having further circuitry for providing an error between said load and said reference potential, and having still further circuitry (250) for summing the channel signals, average signal, and error for providing a respective drive signal for each of the power switches, wherein the error signal and the average signal have complementary effects on a duty factor of the drive signals and the channel signal has an effect contrary to the error signal and the average signal. Further, a plurality of pulse width modulators (305) can be combined as a system (300) by connecting respective nodes (221) for providing current sharing between all phases.

The invention discloses a design scheme of an energy storage bidirectional current converter for a high-capacity storage battery. The current converter utilizes a modularization design idea and supports the idea that a plurality of branch DC / DC modules are connected in parallel and then are connected to a DC bus bar. The problems of circulation and current sharing caused by serial and parallel connection of battery packs are solved. Energy collected by the DC bus bar is exchanged with the energy of a power grid or an independent load through a backward DC / AC current converter. Due to the adoption of a technology of time-sharing rotation and dynamic hibernation, the efficiency of a system under the low power and electric energy quality at the AC and DC sides can be effectively improved so as to realize balanced use of the battery packs. Each storage battery branch is subjected to automatic and intelligent charge and discharge management, a control function and a protection function are completely independently configurated, and the highest availability of the system is ensured. An experimental result shows that the energy storage bidirectional current converter for the high-capacity storage battery has good universality, practicality and application prospect.

The invention relates to the field of direct current (DC) / DC conversion and rectification, and aims to provide a multiphase current-sharing controlled parallel-connection adjusting circuit and a control method. The circuit comprises n phases of adjusting circuits connected in parallel, the structure of each phase of the adjusting circuits are identical; each phase comprises a main transformer and an auxiliary transformer; a primary side winding of the master transformer and a primary side winding of the auxiliary transformer in each phase of circuits are connected in series and then connected in parallel to two ends of an equivalent alternating input power supply PN; secondary side windings of the main transformers in two outputs penetrate through the rectification circuit and then are directly connected to the right end of a current device output side, and the other end is grounded; a secondary winding of the auxiliary transformer in another circuit penetrates through the rectification circuit and then is connected to the input end of a DC-DC converter, and the output end of the DC-DC converter is connected in parallel to the current device output side. Current sharing among multipath transformers is achieved by controlling the balance of power of a small-power DC-DC module; the feedback is realized on a secondary side, the feedback signal can be transmitted to a primary side without isolation, and the system reliability is improved.

An LED driver includes at least two interlocked closed feedback loops. One feedback loop controls the duty cycle of the on / off times of a switch connected in series to the LED string, and the other feedback loop controls the duty cycle of the on / off times of a power switch in the switching power converter that provides a DC voltage applied to the LED string. The LED driver of the present invention achieves fast control of the LED brightness and current sharing among multiple LED strings simultaneously in a power-efficient and cost-efficient manner.

An active current sharing circuit that provides a plurality of paralleled DC-DC converters each having a lossless inductor-based current sensing circuit for sensing the average current of the associated DC-DC converter through its output inductor, and a means for adjusting the voltage reference coupled to each of the DC-DC converter's PWM controllers through a one pin interconnection between the converters. The circuit provides a high percentage current sharing level at lower cost, with reduced circuit wiring complexity, and fewer components. In an alternate embodiment, the inductor-based current sensing is replaced with a resistor-based current sensing, such that comparable current sharing levels are achieved albeit with higher loss.

The invention provides a parallel current sharing circuit of a charging module of an electric automobile charger, comprising a charger monitoring unit and at least one charging module which are connected in parallel, wherein the charging modules are linked in parallel; the charger monitoring unit is connected with the charging modules through communication signal lines; and the charging modules are connected through average current signal lines, and connected with a grid alternating current end and a power battery direct current end of the electric automobile respectively. By using the current sharing circuit disclosed by the invention, the sampling feedback coefficient of the output voltage of the module is adjusted according to the differential value between a module charging current sampling signal and average current signals of all the parallel modules, thus the charging voltage and the charging current of the module are further adjusted to reach the purpose of load-sharing current in parallel of every charging module. The parallel current sharing circuit has relatively high current sharing precision and current sharing dynamic responding speed, is beneficial to improving the reliability and the maintainable performance of the charger and better satisfies the charging requirement of the power battery of the electric automobile.

The provided method and control circuit are employed to alternately control the dual boost PFC circuits. The control circuit for alternately controlling parallel-connected first and second boost circuits of a dual boost PFC circuit to achieve a current-sharing of the first and the second boost circuits includes: a first control circuit having a first current control loop for employing an output voltage of the PFC circuit, a feed-forward voltage, and an input reference voltage to generate a current reference, and sending the current reference to an input terminal of the first current control loop to generate a first PWM signal to drive the first boost circuit, and a second control circuit having a second current control loop for receiving the current reference through an input terminal of the second current control loop to generate a second PWM signal to drive the second boost circuit.

A power system for providing an output current at a regulated system output voltage includes a first power stage and a second power stage, each being a constant on-time (COT) controlled power converter. The first and second power stages generate respective first and second regulated output voltage having reduced or very small output ripple at a common output voltage node. The first and second power stages each includes a ripple injection circuit to inject a ripple signal to the feedback control circuit in each power stage. The power system further includes a current sharing control circuit configured to measure a first output current of the first power stage and a second output current of the second power stage, and to generate a control signal to modulate the feedback control circuit of the second power stage to force the second output current to equal to the first output current.

The invention relates to a voltage conversion device in the electronic power system in order to simplify the loop structure, save switch devices and solve the issues of bidirectional flow of the power as well as the equal flows in the low voltage stages. The device includes 1-4 phases. Each phase is independent with the identifical structure composed of the high voltage stage, the isolation stage and the low voltage stage. The high voltage stage includes 2-30 identical power conversion modules in serial. The isolation stage includes the part of the modulation / demodulation in high frequncies etc. The low voltage stage includes the power conversion module. Comparing with the foreign scheme, the number of the devices is reduced one-third, and the cost also is reduced.

A power supply in an embodiment of the invention includes a plurality of dc-dc switching power converters, each of which has its input isolated from its output. The power converters are arranged with their respective inputs being series connected and their respective outputs being parallel connected in an embodiment of the invention. In another embodiment of the inputs are parallel connected and the outputs series connected. Each power converter includes an input filter in each of said dc-dc switching power converters and an output filter. Each power converter includes a sensorless current mode control circuit controlling its switching duty ratio.