52 results about "Valley-fill circuit" patented technology

An electronic ballast for driving a gas discharge lamp includes a rectifier, a valley-fill circuit, an inverter having first and second series-connected controllably conductive switches having complementary duty cycles, a control circuit for controlling the controllably conductive switches, and an independent cat ear power supply to provide power to the ballast control circuits. The result is a ballast having substantially improved power factor, THD, and current crest factor. In a preferred embodiment, the valley-fill circuit includes an energy storage device that stores energy in response to a controllably conductive switch. In an especially preferred embodiment, the controllably conductive switch of the valley-fill circuit is also one of the switches of the inverter.

An electronic ballast for driving a gas discharge lamp includes a rectifier to convert an AC mains input voltage to a rectified voltage, a valley-fill circuit for producing a DC bus voltage, an inverter for converting the DC bus voltage to a high-frequency AC voltage for driving the lamp, a control circuit for controlling the inverter, and a flyback cat-ear power supply for supplying current to the inverter when the rectified voltage is less than a predetermined level. The flyback cat-ear power supply also provides power to the control circuit. Preferably, the flyback cat-ear power supply draws current only when the inverter is not drawing current directly from the AC mains, so as to make the input current to the ballast substantially sinusoidal. The result is a ballast having substantially improved power factor and THD. Also, the ballast operates more efficiently because the flyback cat-ear ear power supply supplies excess energy not needed by the ballast control circuitry to the inverter to be used to drive the lamp.

The invention discloses an active-control valley fill circuit and a control method thereof which are mainly applied to pre-stage power factor correction and energy accumulation of a switching power supply. The active-control valley fill circuit comprises an alternating-current power supply, a current rectifier, a load, an energy storing capacitor, a switch circuit and control circuit, the alternating-current power supply is connected with an input end of the current rectifier, an output end of the current rectifier is connected with the load, the switch circuit comprises two power ends and a control end of a power channel, the energy storing capacitor is serially connected with the two power ends of the switch circuit and is then parallelly connected with an output end of the current rectifier, and the control end of the switch circuit is connected with the control circuit. According to the control method, by means of presetting threshold voltage, switching between power supplying of the load and energy storing of the energy storing capacitor is realized according to changes of relationships among alternating-current phase position voltage, voltage at two ends of the energy storing capacitor and the threshold voltage. The active-control valley fill circuit has the advantages that a circuit structure is simple, a power factor is improved, output voltage is not higher than alternating-current crest voltage, and the minimum value of the output voltage can be set.

Provided herein is a power factor correction (PFC) power supply, comprising: a bridge rectifier having an input and an output, a filter capacitor connected to the output of the bridge rectifier, a transformer having a primary winding, a fly-back winding and a secondary winding, a forward diode, a fly-back diode, a storage capacitor circuit having a valley-fill circuit and a capacitor connected in parallel, and a switch connected between the primary winding and the output of the bridge rectifier. The PFC power supply features improved efficiency and low switching loss.

An electronic ballast for driving a gas discharge lamp includes an EMI filter, a bridge rectifier coupled to a DC bus without a conventional electrolytic capacitor, a passive valley fill circuit built as a network having 4 charge / discharge energy storage capacitors and 9 diodes (4C9C), and a resonant DC to AC high frequency inverter for powering gas discharge lamp. The 4C9D circuit divides the rectified peak voltage by four and the low output voltage of the circuit is used to provide continuous lamp operation. The result is a ballast having substantially improved power factor, total harmonic distortion, and current crest factor. The electronic ballast is provided with a dimming capability from a TRIAC based wall dimmer.

The present invention discloses a power supply circuit for driving an LED lamp and a power supply method. The power supply circuit is constituted by an AC-DC converter by adopting DCM-DCM. Also, the power supply circuit adopts a valley fill circuit to reduce rippling of output current and adopts the DCM-DCM to stabilize a link voltage, thereby realizing a power factor correction circuit having two-stage structures. Thus, an input voltage of the flyback converter may be improved, and a high reverse voltage may be applied.

The invention discloses a flyback switching power circuit. A valley filling circuit is adopted in a filter circuit of the flyback switching power circuit. The work voltage of a capacitor C1 and the work voltage of a capacitor C2 in the valley filling circuit are reduced by a half, -40 DEG C electrolytic capacitor can be adopted, and a third capacitor C3 is in parallel connection to a charging diode D3 in an existing valley filling circuit, so that the withstand voltage of the third capacitor C3 is half of a peak value of input pulse direct current, and high-frequency ripple current of a back switching power 300 can be fully and effectively absorbed. A varistor RV1 and a varistor RV2 are arranged before and behind a rectifier bridge 101, and a thermistor NTC, a safety capacitor X1 and an inductor L form a multi-level two-way filter and protection circuit. The flyback switching power circuit has the advantages that the power factor is high and not affected by a value of the C3, the topological structure of the circuit is simple, the absorption effect on surging voltages is good, cost is low, the size is small, and the difference mode conduction interference degree of the flyback switching power circuit reaches the CLASS B in GB9254.

An embodiment of the invention discloses an LED power supply with high power factors. The LED power supply comprises a resistive and capacitive voltage relief circuit, a rectifying bridge pile and a valley fill circuit. The resistive and capacitive voltage relief circuit is connected to the input end in series and relieves voltage on the input voltage, and the relieved voltage is rectified by the rectifying bridge pile; the valley fill circuit is connected to the output end of the rectifying bridge pile in parallel and increases the power factors of the circuit. By the aid of the LED power supply, voltage is relieved by using the resistive and capacitive voltage relief circuit, transformer usage is avoided, space is saved, and the power factors of the circuit is increased by using the valley fill circuit.

The present invention relates to a circuit arrangement for operating at least one light source. Cost-effective power factor correction of the system input is achieved by a combination of a charge pump and a valley-fill circuit. According to the invention, the voltage (UN2) produced by the charge pump is fed into the valley-fill circuit with a lag, for example by means of an inductor (L2).

The invention provides a valley fill circuit with the protection function. A charging diode D3 of an existing valley fill circuit is connected with a third capacitor C3 in parallel, so that the withstand voltage of the third capacitor C3 is a half of the maximum peak of input pulsating direct currents, and high frequency ripple currents of a later-stage switching power source 300 can be fully and effectively absorbed. The front and the back of a rectifier bridge 101 are provided with a multi-stage double-direction filter circuit composed of a voltage dependent resistor RV1, a voltage dependent resistor RV2, a thermistor NTC and a safety capacitor C and a protection circuit composed of an inductor L respectively. The valley fill circuit has the advantages that the power factor is large, the value of the C3 does not influence the power factor, the circuit topology structure is simple, the absorbing effect on surge voltage is good, the cost is low and the size is small. When the later stage is the switching power source, the difference module conducted interference degree accords with the grade of CLASSB in GB9254.

The invention discloses a driving power source for a smart LED bulb. The driving power source comprises an EMI filtering circuit, a rectifying circuit, a power factor correcting circuit, a power converting circuit, a DC-DC converting circuit and a dimming control circuit, wherein the power factor correcting circuit comprises a valley filling circuit and an electrolytic capacitor connected to the valley filling circuit, and the output end of the valley filling circuit is connected with the input end of the power converting circuit; the power converting circuit is a primary side feedback power converting circuit, and the output end of the power converting circuit is connected with the dimming control circuit; the dimming control circuit comprises a single-chip microcomputer control module and an MOS transistor, the input end of the DC-DC converting circuit is connected with the output end of the power converting circuit, the output end of the DC-DC converting circuit is connected with the single-chip microcomputer control module, and the switch-on duty ratio of the MOS transistor is controlled through the single-chip microcomputer control module so that dimming and color modulation on loads can be achieved. The driving power source for the smart LED bulb is low in cost, small in size and low in power consumption; the driving power source meets the requirement for a high power factor and the requirement for non-flickering lighting of the bulb at the same time.

An embodiment of the invention discloses an LED power supply circuit which comprises a voltage reducing circuit, a filter, a rectifier bridge, a valley fill circuit and two groups of LED loads. The voltage reducing circuit consists of a resistor and a capacitor which are connected in parallel and is connected to the input end in series, the filter is an LC filter and performs high-frequency filtering on reduced voltage, the rectifier bridge performs full-wave rectification on filtered voltage, the valley fill circuit is connected to the rectified voltage output end of the rectifier bridge in parallel, and two groups of LED loads are of same-number structures and connected to the output end. By adopting the LED power supply circuit, input pulsating wave forms can be rectified, and the circuit power can be improved to be higher than 0.9. In addition, the LED power supply circuit can be combined with different forms of loads.

The electronic ballast circuit is connected electrically to an input power supply to provide input voltage. The electronic ballast circuit includes one rectifier connected to the input voltage for rectifying and providing one first voltage; one electric energy converter to switch and output the HF component in the first voltage and to provide electric energy to the load; and one valley fill circuit connected to the output of the electric energy converter and the output of the rectifier. When the first voltage is higher than some set value, the electric energy converter is switched to charge the valley fill circuit; and when the first voltage is lower than the set value, the valley fill circuit is used to make up the first voltage, with the set value being regulated in designing the valley fill circuit.

The invention discloses an LED drive device with a valley fill circuit. The device includes a bridge rectification module connected to commercial power, a valley fill circuit, a filter capacitor C3, a constant current module connected to the bridge rectification module, and an LED load connected to both the bridge rectification module and the constant current module. One end of the filter capacitor C3 is connected to the output end of the bridge rectification module, and the other end of the capacitor C3 is connected to the ground. The valley fill circuit is connected to the output end of the bridge rectification module. The valley fill circuit is additionally adopted to greatly increase a conduction angle of a rectifier diode, input currents are made to change from spike pulses into waveforms similar to sine waves through valley point filling, the total harmonic distortion is substantially reduced, and a power factor can be increased to be around 0.9. The LED drive device has the advantages of simple structure and low cost.

The invention discloses a simple and practical harmonic wave improved LED drive circuit. The circuit includes a bridge rectification module, and a constant current module, an LED load, an electromagnetic interference filter and a valley fill circuit that are connected to the bridge rectification module. The bridge rectification module is connected to commercial power through the electromagnetic interference filter. The valley fill circuit is connected to the output end of the bridge rectification module. The electromagnetic interference filter is in series connection between an AC wire inlet end and the bridge rectification module to filter electromagnetic interference, harmonic waves are improved by improving of a conduction angle input to a rectification filter circuit, the valley fill circuit is utilized to fill the circuit, and total harmonic wave distortion is minimized. Therefore, harmonic wave components are prevented from polluting a power grid, and active power is guaranteed. The drive circuit has the advantages of simple structure and low cost.

In a circuit arrangement for operating light sources, inexpensive technologies for power factor correction can be used in combination. Owing to the combination of a dual charge pump and a valley fill circuit it is also possible to adhere to relevant standards for rated current harmonics even at rated powers of over 25 W whilst maintaining low component loading.

The invention discloses an LED linear constant current driving circuit in an active valley fill circuit mode. The LED linear constant current driving circuit comprises a rectifier bridge, a capacitor C1, a diode D1, a diode D2, a diode D3, a diode D4, an LED light string, and a constant current module. The constant current module comprises an NMOS tube N1, a first operational amplifier, an NMOS tube N2, and a second operational amplifier. In a power frequency period, the LED light string is used for the charging and the energy storage of the capacitor C1 by the constant current, and the energy stored in the capacitor C1 is used for discharging the current to the LED light string by the constant current, and therefore under a condition of large voltage differences between a direct current input voltage and the voltages of the two ends of the LED light string, the efficiency of the whole linear constant current driving circuit is improved, and the current flowing through the LED light string has smaller power frequency ripples.

The embodiment of the invention discloses a power supply, a power supply method and a computer storage medium. The power supply comprises a rectifying circuit and a valley fill circuit. The rectifyingcircuit is used for carrying out voltage conversion on input alternating-current voltage to obtain first pulsating direct-current voltage; the valley fill circuit comprises at least one energy storage capacitor and is used for storing energy through the at least one energy storage capacitor when the first pulsating direct-current voltage output by the rectifying circuit is in a first preset interval; and when the first pulsating direct-current voltage output by the rectifying circuit is lower than a preset threshold value, energy is provided through the at least one energy storage capacitor,so that the trough voltage of the first pulsating direct-current voltage is increased. Thus, the stability of the output voltage can be ensured by adopting a capacitance valley-fill technology, the circuit is simple, the reliability is high, and meanwhile, the volume of the power supply can be reduced.

The invention relates to a high-efficiency passive power factor correction circuit, which comprises a rectifier bridge circuit, an output circuit and a mutual induction valley fill circuit; and the mutual induction valley fill circuit is connected in parallel between bridge arms of the rectifier circuit and the output circuit. The rectifier bridge circuit is composed of a first diode D1, a second diode D2, a third diode D3 and a fourth diode D4; the mutual induction valley fill circuit is composed of a fifth diode D5, a sixth diode D6, a seventh diode D7, an eighth diode D8, a first capacitor C1, a second capacitor C2 and a transformer T1; and the output circuit comprises a third capacitor C3.

The invention provides a power supply device and a charging method. The power supply device comprises a first-stage conversion circuit, a second-stage conversion circuit and a valley fill circuit. Thefirst-stage conversion circuit is used for converting a rectified direct-current voltage to obtain a first direct-current voltage; the second-stage conversion circuit is used for converting the firstdirect-current voltage and outputting a second direct-current voltage, and the second direct-current voltage is lower than the voltage value of the first direct-current voltage; and the valley fill circuit is used for providing energy for the output end of the power supply device when the second direct-current voltage is lower than a set value so that the output voltage of the power supply deviceis constant direct-current voltage. According to the technical scheme, the size of the power supply device can be reduced.

The invention provides a high-power factor valley-filled circuit for driving a switch type load and a switching power supply. The high-power factor valley-filled circuit comprises three ports, wherein the first end of a first switching tube is the first port; the first end of the first switching tube is connected with the positive output end of a pulsating DC power supply, and the second end of the first switching tube is connected with a first joint; the first end of a second switching tube is connected with the first joint, and the second end of the second switching tube is connected with the negative output end of the pulsating DC power supply; the second end of the second switching tube is the second port; the first end of a first inductor is connected with the positive output end of the pulsating DC power supply, and the second end of the first inductor is connected with a second joint; the second joint is the third port; the first end of a first capacitor is connected with the first joint, and the second end of the first capacitor is connected with the second joint; the switch type load is connected between the second port and the third port. The first capacitor in the circuit can be a low-voltage capacitor, so the types of the capacitor can be selected easily; power factors can be controlled by adjusting the conduction angle of a rectifier bridge.

The invention discloses a valley filling circuit. A third capacitor C3 is connected to a charging diode D3 in an existing valley filling circuit in parallel, and therefore the withstand voltage of the third capacitor C3 is half the peak value of the input pulsating direct current, and the high-frequency ripple current of a back-stage switching power supply 300 can be fully and effectively absorbed. Due to the fact that the third capacitor does not directly discharge to a load 300, the power factor of the valley filling circuit is large, no high-voltage capacitor which is high in cost and large in size is needed, the capacity value of the third capacity is easy to obtain, and no average striking is needed.

The embodiment of the invention discloses a power supply device, and a charging method and system. The power supply device comprises a rectification module used for rectifying an AC voltage to obtain a first pulsating DC voltage, a conversion module used for converting the first pulsating DC voltage to obtain a stable DC voltage, and a valley filling circuit which is connected with the rectification module and the conversion module, and is used for boosting the first pulsating DC voltage output by the rectification module when the voltage value of the first pulsating DC voltage is greater than a first voltage threshold value, and storing energy based on the boosted first pulsating DC voltage; and when the voltage value of the first pulsating DC voltage is smaller than a second voltage threshold value, electric energy is provided for the conversion module so that a trough voltage of the first pulsating DC voltage input to the conversion module is increased. According to the power supply device, the charging method and system, the size of the power supply device can be reduced, and the stability of the output voltage of the power supply device is ensured.

The embodiment of the invention discloses a power supply device, a charging method and system, and a computer readable storage medium. The power supply device comprises a rectification module used forrectifying an AC voltage to obtain a first pulsating DC voltage, a primary conversion circuit, a secondary conversion circuit and a valley fill circuit, wherein the primary conversion circuit is connected with the rectification module and is used for carrying out isolation conversion on the first pulsating DC voltage to obtain a second pulsating DC voltage; the secondary conversion circuit is connected with the primary conversion circuit and is used for converting the second pulsating DC voltage to obtain a stable DC voltage; and the valley fill circuit is connected with the primary conversion circuit and is used for providing electric energy for the input of the primary conversion circuit when the voltage value of the first pulsating DC voltage is lower than a first voltage threshold value so as to increase a valley voltage of the first pulsating DC voltage. According to the power supply device, the charging method and system, and the computer readable storage medium, the size of thepower supply device can be reduced.