342 results about "Flyback transformer" patented technology

The invention relates to series battery equalizing equipment. Each battery of a plurality of batteries connected in series is connected with an equalizing module, and the equalizing module comprises a diffluence module and a flyback transformer unit. The diffluence module of the equalizing module spans two adjacent single batteries. In the diffluence module, a grid electrode of a switching tube MOSFET is connected with the anode of the first single battery; a source electrode of the switching tube MOSFET is connected with an energy storage inductor; a gate electrode is connected with a controller; the energy storage inductor is connected with the cathode of the first single battery; the cathode of a diode is connected with the source electrode of the MOSFET; and the anode of the diode is connected with the cathode of the second battery. The flyback transformer unit is characterized in that a grid electrode of the switching tube MOSFET for controlling a flyback transformer is connectedwith the anode of a third battery; the source electrode is connected with a primary side same polarity of the transformer; the gate electrode is controlled by the controller; a primary side synonyms polarity and a vice-side same polarity of the flyback transformer are both connected with the cathode of the third battery; a vice-side synonyms polarity of the flyback transformer is connected with the anode of a protection diode of the flyback transformer; and the cathode of the protection diode is connected with the anode of the first battery.

The invention relates to a forward-flyback two-way DC-DC converter, composing a forward transformer by coupling secondary and primary windings; composing a flyback transformer by coupling another secondary and primary windings, where the two secondary windings are connected in series with the two switches tubes, respectively, and then connected in parallel with a DC power supply. The two primary windings are connected in series and then connected in parallel with a DC power supply through rectifier/inverter. It uses active clamping, RCD clamping, LCD clamping, ZVT and other techniques to compose a family of two-way converter topologies. It uses the forward transformer and a coupling inductance together to transmit energy, solving the defect in using transformer leakage inductance or coupling inductance to transmission energy; avoids the peak problem in current topologies in existing techniques; has the advantages of small current ripple, implementing soft switch for each switch tube, etc.

The embodiment of the invention provides a method for constantly outputting current, comprising the following steps: an input circuit receives externally input voltage, and a drive controller and a power switch are in operating condition; the controller controls the power switch to ensure that a peak value of input current IP of the power switch is a constant value and a product of a switching frequency f of the power switch and degaussing time Tdemag of a flyback transformer is a constant value, that is, Tdemag*f=c, wherein, c is a constant; and the current input end of the power switch is connected with a primary coil of the flyback transformer, wherein, primary current on the primary coil is IP, an auxiliary winding signal of the flyback transformer is fed back to the input circuit, and output current on a secondary coil is rectified and filtered through an output circuit to obtain constant output current which is provided to load. In the technical scheme provided by the invention,the switching frequency of the power switch can be adjusted by the degaussing time, thus eliminating influence of output current deviation of a power supply system caused by transformer inductance variation, and improving accuracy of the output current.

Systems and methods for extending the useable capacity of a battery pack are disclosed. In one example, flyback transformers supply charge to lower capacity battery cells to extend battery output.

The invention discloses an electrolytic capacitor-free LED driving power supply based on flyback converter leakage inductance energy utilization. The power supply comprises an alternative current input power supply, a bridge rectifier circuit, an auxiliary circuit, a main switch tube, a flyback transformer, a rectifier circuit, an output filter capacitor and an LED load. The power supply has the characteristics and advantages that firstly, as energy storage capacitance voltage of the auxiliary circuit is designed into a working mode that direct current voltage is overlapped with large pulse ripple voltage, not only is the dependence of the LED driving power supply on an electrolytic capacitor eliminated, but also flyback converter leakage inductance energy utilization is achieved; secondly, the flyback transformer works in a current interrupted mode, and input power factor correction is achieved; thirdly, due to adoption of the auxiliary circuit, the low frequency pulse power of input power pin and output power po can be balanced, and the constant current can be achieved to drive the LED load through coordination work of the auxiliary circuit and a main circuit.

The arc suppression system for electrical contacts includes a transistor, such as an IGBT, which is connected across the contacts. A control circuit controls the operation of the transistor such that the turning on of the transistor results in a current path around the contacts, thereby tending to prevent arcing across the contacts. A current sensor, such as a flyback transformer, is positioned in series with the contacts, wherein when the contacts open, current is interrupted through the contacts and the transformer, a secondary voltage results which is applied to the transistor, which tends to maintain the transistor on for a time which is sufficient to allow the contacts to either open or close without an arc.

A flyback power converter includes a hybrid clamp circuit and a corresponding power management unit that substantially optimizes the performance of the flyback power converter in its entire line and load ranges. The clamp circuit, which is connected in parallel to a primary winding of the flyback transformer, includes a parallel combination of a capacitor and resistor that is connected in series with a parallel combination of a switch and a diode. By sensing the operating conditions, the power management circuit configures the clamp circuit either as a passive clamp or as an active clamp. In the passive-clamp configuration, the switch is kept turned off. In the active-clamp configuration, the switch operates with pulse-width modulation (PWM) which enables ZVS turn-on of the main switch.

An electronic flash charger having an electronic flash charging circuit of a separate excitation oscillating. The charger includes: a flyback transformer, having at least a primary coil and a secondly coil; a switching element for turning on or off electric power, to be supplied to the primary coil, based on control signals supplied to a control input terminal; a rectifying diode for rectifying a flyback pulse generated on the secondly coil when the switching element is changed from ON state, that the electric power is turned on, to OFF state, that the electric power is turned off; a main capacitor for charging a current rectified by the rectifying diode; and an oscillation controller for generating control signals for changing at least one of time spans of ON state and OFF state of the switching element in accordance with a period from generation to extinction of the flyback pulse generated on the secondly coil, and for supplying the control signals to the control input terminal of the switching element.

The invention discloses an active equalization system for a power battery pack and a control method, and belongs to the technical field of battery management. The active equalization system comprisesa power battery pack, a monitoring and collecting module, a master control module, an equalization control module and an equalization circuit module; one end of monitoring and collecting module is connected with all battery cells in the power battery pack, the other end of the monitoring and collecting module is connected with the master control module, the master control module is connected withthe equalization control module to perform two-way communication, and the driving end of the equalization control module is connected with the power battery pack through the equalization circuit module. According to the active equalization system, based on an equalization circuit of a flyback transformer, energy is transferred between the batteries and not dissipated in a resistance mode, and therefore the equalization efficiency is improved. In addition, a battery simulator is adopted for replacing the real power battery pack, the method for control over the simulator is integrated to verifyequalization experiments of the equalization system under charging, discharging and standing, and the high efficiency of the system is verified.

The high performance polyphenylene ether composition consists of polyphenylene ether 40-90 weight portions, polyethylene resin 5-30 weight portions, TPE elastomer 1-10 weight portions, phosphorus containing organic flame retardant 4-18 weight portions, lubricant 0.1-0.3 weight portions, and antioxidant 0.2-0.4 weight portions. The composition has high rigidity, high heat resistance, high size stability, excellent flame retardant property, etc. and may be used in flyback transformer part, deflection coil skeleton, convergent magnetic assembly skeleton, casing of various electronic and electric parts, etc.

Disclosed is a PWM controller with programmable switching frequency for PSR/SSR flyback converter so as to maximize the performance-to-cost ratio by tailor-making the switching frequency as a non-decreasing function of the output load and the maximum switching frequency as a non-increasing function of the input voltage, leading to a plurality of programmable voltage-dependent frequency-load curves, making possible the downsizing of flyback transformer while facilitating the simultaneous compliance with DoE and CoC efficiency requirements.

A signal is described herein that provides light output for automotive, rail, ship traffic and/or illumination control that includes a light emitting diode (LED) array, wherein the LED array includes three groups of disparate colored LEDs. A power supply unit provides independent power to each of the three LED groups. Each LED group power supply unit includes an input controlled switch connected to a power line to provide power to the LED array. An input under voltage/over voltage circuit monitors the voltage level of the power line and for enabling and/or disables the input controlled switch according to the voltage level of the power line. A flyback transformer converts the power received from the power line from an alternating or a continuous current signal to a direct current signal output to the LED array. A dummy load draws power additional to the LED array and a dummy load detection circuit monitors the dummy load to insure that the power drawn by the load is greater than or equal to a predetermined threshold. A light out detection circuit monitors the light output of the LED array via an optical sensor.

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 transformer fault analysis method. The method includes the steps that a historical faulty transformer is obtained, fault causes of the historical transformer are analyzed, and the fault state quantity of the historical transformer is extracted; a transformer fault database is built, and the fault causes of the historical transformer and the fault state quantity of the historical transformer are stored in the transformer fault database; fault state information of a to-be-detected faulty transformer is obtained; the transformer fault database is inquired, the fault state information of the to-be-detected faulty transformer is analyzed, and fault causes of the to-be-detected faulty transformer are obtained. The invention further provides a transformer fault analysis system. The transformer fault analysis method and system are beneficial to improving power transformer fault judgment efficiency, and a power transformer is prevented from being detached before fault judgment.

The invention discloses a step-up converter for high speed solenoid valve driving, which belongs to the field of high actuator driving. The step-up converter aims to overcome the shortcomings of a single-inductor step-up circuit and a flyback transformer, combines the advantages of a single-inductor step-up way and a flyback transformer step-up way, adopts a centre-tapped transformer as a step-up inductor, achieves improvements in step-up ratio, working frequency, inductor volume and working efficiency, and can reduce system cost and improve the level of integration; and a centre-tapped transformer step-up way combines the advantages of transformer step-up and inductor step-up, is particularly suitable for high voltage production for the high speed solenoid valve driving, and ensures an output voltage range of 80 to 150V.

A switching amplifying method or a switching amplifier for obtaining one or more than one linearly amplified replicas of an input signal, is highly efficient, and does not have the disadvantage of “dead time” problem related to the class D amplifiers. Another aspect of the present invention provides a switching amplifier that is completely off when there is no input signal. Yet another aspect of the present invention provides a switching amplifier for obtaining a plurality of different linearly amplified replicas of the input signal, and adds more slave outputs easily and economically.

The present invention discloses an isolated type interleaving DC/DC converter with a switching capacitor, comprising two power switching tubes, two output diodes, two clamping diodes, two auxiliary power switching tubes, two clamping capacitors, two switching capacitors, one output capacitor and two flyback transformers. The converter uses the second windings and two switching capacitors of two flyback transformers to realize the improvement of the output power level of the converter. Two auxiliary switching tubes and two clamping capacitors are respectively used for absorbing the leakage inductance energy of the two flyback converters. The parallel capacitors existed in the two power switching tubes and the gate pole arrangement of the two power switching tubes and the two auxiliary switching tubes are used for realizing the zero voltage cutover and the zero voltage shutoff of the two power switching tubes and the two auxiliary switching tubes. The leakage inductance of the two flyback converters is used for realizing the soft shutoff of the two output diodes and the two clamping diodes. The circuit has no dissipative elements, and the power class and the circuit efficiency of the converter can be improved.

A multi-stage flyback circuit is provided for a wide range of DC input voltage applications. An intermediate circuit is coupled across a DC source which may be for example an output from a diode bridge rectifier. A first flyback stage includes a primary winding of a flyback transformer and a first switch coupled in series between a midpoint of the intermediate circuit and a negative DC terminal. A second flyback stage includes a second primary winding and a second switch coupled in series between the midpoint of the intermediate circuit and a positive DC terminal. A secondary winding of the flyback transformer is coupled to a DC load. The first and second switches are operated synchronously, wherein the voltage stress on each of the first and second switches is substantially reduced.

The present invention discloses a half-bridge flyback resonant circuit. The half-bridge flyback resonant circuit comprises a half-bridge circuit comprising an upper bridge arm and a lower bridge arm,wherein the upper bridge arm and the lower bridge arm are connected in series between an anode and a cathode of an input power, and the upper bridge arm and the lower bridge arm are respectively provided with switch elements which are used for switching on and off in turn; a primary input circuit being connected in parallel with the lower bridge arm and comprising an energy storage element and a primary winding of a flyback transformer, wherein a dotted terminal of the primary winding is connected between the upper bridge arm and the lower bridge arm, and a non-dotted terminal of the primary winding is connected with the cathode of the input power through the energy storage element; and a flyback secondary circuit configured to output an appropriate output voltage and comprising a secondary winding of the flyback transformer, wherein a non-dotted terminal of the secondary winding is taken as an anode outputting the output voltage, and a dotted terminal of the secondary winding is takenas a cathode outputting the output voltage. The half-bridge flyback resonant circuit improves the efficiency, reduces the cost, improves EMI, and is especially suitable for but not limited to a low-power source with high-voltage input and an auxiliary power source.