51results about How to "Corrected power factor" patented technology

A power supply apparatus, such as an uninterruptible power supply, includes an AC input configured to be coupled to an AC power source and an AC output. The apparatus also includes an AC/DC converter circuit, e.g., a boost rectifier circuit, with an input coupled to the AC input. The apparatus further includes a DC/AC converter circuit, e.g., an inverter circuit, configured to be coupled between an output of the AC/DC converter circuit and the AC output. A bypass circuit is operative to establish a coupling between the AC input to the AC output in a first (e.g., bypassed) state and to interrupt the coupling in a second (e.g., “on line”) state. The AC/DC converter circuit is operative to control current at the AC input when the bypass circuit is in the first state. For example, the AC/DC converter circuit may be operative to control current at the AC input to correct a power factor at the AC input port when bypassed, such that the AC/DC converter circuit may act as a line conditioner in the bypassed state.

A Power Factor Correction (PFC) system providing near unity power factor for an AC power source (VAC) connected to a complex load. The system includes a bridge rectifier, boost or buck-boost converter, complex load, and pulse width modulation (PWM) controller to provide pulses with variable duty cycle to a power switch. The invention is a constant pulse proportional current (CPPC) PWM controller that generates trains of pulses constant in frequency and duty cycle for one semi-cycle of the VAC. The duty cycle of the driving signal is modified by applying open-loop correction signals to summing nodes of PWM circuits. Since the PWM provides a constant train of driving pulses with constant duty cycle for one semi-cycle of the VAC, the current absorbed by the converter is contingent and linearly proportional to the voltage. Thus, the output current follows the voltage resulting in a power factor of near unity.

A flyback converter utilizes a boost inductor coupled between a source of AC power and a bridge rectifier to provide power factor correction. A primary winding of the flyback transformer is coupled in series with a storage capacitor across the output of the bridge rectifier. A circuit, which includes a switching transistor, is also coupled across the output of the bridge rectifier to provide a low resistance path when the switch is closed. The cores of the boost inductor and the transformer are loaded with energy when the switch is closed. When the switch opens, the energy stored in the magnetic cores is transferred to the output via the transformer secondary winding and rectification circuitry.

A one cycle power factor correction converter circuit comprising a switch for controlling a DC output voltage of the converter circuit, the switch being switched by a drive signal having a frequency determined by a clock signal; the converter circuit being provided with a DC input voltage and producing the DC output voltage, the DC input voltage being rectified from an AC input; a controller circuit for controlling an on-time or off-time of the switch to set the output voltage and to achieve power factor correction at the AC input; the controller circuit comprising an error amplifier receiving a feedback voltage from the output of the converter circuit and a reference voltage and producing an error signal; a ramp generator receiving the error signal and generating a first ramp signal by integrating a signal related to the error signal; a pulse width modulation circuit receiving the first ramp signal and a signal related to the error signal and producing a pulse width modulated signal by comparing the first ramp signal and the signal related to the error signal; the pulse width modulated signal determining the on-time or off-time of the switch to control the output voltage with power factor correction; further comprising a circuit for terminating the first ramp signal when a predetermined inequality exists between the first ramp signal and a reference signal and for developing the clock signal from the first ramp signal.

A phase-control dimming electronic ballast system and the control method thereof, wherein the system includes a phase controller, a converter, an inverter and a system controller. Moreover, the system controller senses a firing angle from the phase controller, and adjusts the output voltage of the converter and the switching frequency of the inverter to achieve the operation of dimming fluorescent lamp.

A power factor correction circuit includes; a series circuit connected to a positive-electrode output terminal P1 and negative-electrode output terminal P2 of a full-wave rectifying circuit B1, which rectifies an having current power-supply voltage of an alternating current power-supply Vac1, and including a booster winding 5a and a wind-up winding 5b wound on a booster reactor L1, a diode D1 and a smoothing capacitor C1; a series circuit, connected between the positive-electrode output terminal P1 and the negative-electrode output terminal P2 and having the booster winding 5a, a ZCS reactor L2 and a switch Q1; a diode D2 connected between a junction, between the switch Q1 and the ZCS reactor L2, and the smoothing capacitor C1; and a control circuit 10 that controllably turns the switch Q1 on and off for controlling an output voltage of the smoothing capacitor C1 to a given voltage.

A power converter provides constant load power while achieving a high power factor in a single stage configuration with reduced component count and ratings. The power converter takes a rectified line input to a switching half-bridge that supplies current to a load. A series combination of shunt switch and capacitor is connected across the load to store energy from the input and supply energy to the load. The switches are operated with conduction angles that achieve constant power supplied to the load while drawing a sinusoidal current in phase with the input voltage to achieve high power factor. The circuit provides a simplified configuration over prior power converters that may be used with a resonant load as part of an electronic ballast or an AC-to-DC converter. The power converter configuration and operation also achieves a low total harmonic distortion on the input line power.

A parallel-connected power conversion system of a multi-phase generator configured to provide a power factor correction for a multi-phase generator. The parallel-connected power conversion system includes a parallel-connected power conversion apparatus and a control unit. The parallel-connected power conversion apparatus has a plurality of power conversion units connected in parallel to each other. The parallel-connected power conversion apparatus receives a plurality of generator currents and a plurality of generator voltages generated from the multi-phase generator, and outputs a DC voltage. The control unit generates a plurality of control signals to correspondingly control the power conversion units so that the generator currents linearly follow the generator voltages, therefore the power factor correction of the multi-phase generator is achieved.

The invention relates to an LED circuit, which comprises a power factor control and voltage boosting unit, an LED lamp, and a voltage reduction unit which are connected in turn, a control unit which is connected with the power factor control and voltage boosting unit, the LED lamp, and the voltage reduction unit, and a detection unit, wherein the power factor control and voltage boosting unit and the voltage reduction unit independently work. On the basis of constant current output, the LED circuit can also adjust the phase difference between input voltage and loop current so as to greatly correct power factors and obtain high work efficiency; and compared with the prior art, the LED circuit has flicker-free adjust luminance, good stability and high reliability.

The invention relates to an LED (light-emitting diode) wall wash lamp, which comprises a lamp body, a light-transmitting plate and two hinge pressing bars, wherein the light-transmitting plate is arranged on a light-emitting opening at the top of the lamp body; the two hinge pressing bars are symmetrically arranged at the two sides of the lamp body, and are distributed along the length direction of the lamp body; circular grooves are arranged near outside of the top of the lamp body; the circular grooves are distributed along the length direction of the lamp body; ribs which are distributed along the length direction are arranged near the inner side surface of a neck part of the hinge pressing bar; the ribs are in a cylindrical shape, and are in running fit with the circular grooves; the tail end extending inwards at the top of each hinge pressing bar is suitable for compressing the edge of the light-transmitting plate; the lower end part of each hinge pressing bar is provided with a bolt used for controlling the tail end to compress the light-transmitting plate; under the action of the bolt, the lower end part of each hinge pressing bar is suitable for the side away from the lamp body; and the ribs rotate in the circular grooves, so that the light-transmitting plate is compressed by the tail end.

Disclosed herein is a charger for electric vehicles, which has a wide output voltage range. The charger is a slow charger having an improved configuration to respond to a wide output voltage range as well as output change. The charger may achieve limited switching loss and reduced noise via soft-switching operation, thereby enabling high-efficiency large-power Power Factor Correction (PFC) and increasing conversion efficiency of a DC/DC converter.

A method according to one embodiment may include generating, by a controller, a plurality of control signals to control operations of inverter circuitry to generate an AC signal from a DC signal. The method of this embodiment may also include using the control signals generated by the controller to also control operations of power factor correction (PFC) circuitry, via the inverter circuitry, to enable the PFC circuitry to generate power factor correction of an input source coupled to the PFC circuitry and the inverter circuitry. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.

A switching-mode power supply circuit includes a boost inductor, a boost capacitor, a storage capacitor, a transformer or DC-DC inductor, a first switching component, an output rectification component, a filter capacitor, a feedback and control circuit, first and second rectification circuits. When first switching component conducts, the boost inductor, boost capacitor and first switching component form a first boost loop, the boost inductor stores energy, and the storage capacitor, first switching component and transformer or DC-DC inductor form a first DC-DC loop. When first switching component cuts off, the boost inductor, boost capacitor, storage capacitor and transformer or DC-DC inductor form a second boost loop, and the transformer or DC-DC inductor, output rectification component and filter capacitor form a second DC-DC loop. The filter capacitor supplies energy to a load. The feedback and control circuit drives the first switching component to turn on/off according to a chopping wave having specific frequency and duty to control a voltage, current or power output to the load.

Disclosed are a display apparatus and an electronic apparatus, the display apparatus including: a main body including a display and a connector; and an adapter connectable to the main body and configured to supply power to the connected main body, the adapter including: a transformer configured to boost an input first alternating current (AC) voltage, a switch including a switching device configured to switch a current flowing in the transformer, a controller configured to control the switching device to output a second AC voltage boosted by the transformer, and the main body including a power factor correction (PFC) converter configured to correct a power factor of the second AC voltage output from the adapter and output a direct current (DC) voltage.

A circuit for powering an LED lighting array, the circuit comprising: a transformer for receiving AC line current and stepping down the voltage; one of a rectifier bridge or tapped secondary windings of the transformer paired with steering diodes, for providing a varying DC current; an inductor for receiving the varying DC current so as to smooth out the varying DC current with respect to both voltage and current; and a electrical connection for directing the smoothed-out DC current to the LED lighting array to power the LEDs.

The invention relates to an electrolyser applicable to titanium cathode plates. The electrolyser comprises a electrolyser body, wherein ion exchange membranes are arranged in the electrolyser body and are used for partitioning the electrolyser body into anode chambers and cathode chambers, and a discharging funnel is further arranged at the bottom of the electrolyser body and is connected with the cathode chambers; the titanium cathode plates are arranged between the anode chambers and the cathode chambers; the discharging funnel is connected with a liquid outlet pipe so as to discharge electrolysis waste liquid; and a collection bin which is suitable for collecting precipitated metal is arranged at the bottom of the discharging funnel, and the entrance of the collection bin is connected with the bottom of the discharging funnel. According to the electrolyser, the precipitated metal is collected by the collection bin, so that the precipitated metal can all be collected, the electrolysis operation and the operation collection are separated from each other and are independent from each other, and the electrolysis efficiency is increased.