21 results about "Flyback topology" patented technology

A two-transistor flyback topology in which a portion of leakage inductance energy in the transformer is extracted and used to obtain zero voltage switching on both switching elements in any operating conditions, and in which a third low power switch eliminates parasitic oscillations and allows an operation at a determined frequency. In this topology, there are no switching losses and there are no spikes or glitches in any switching node, eliminating the need for snubbers. This topology is an “ideal two transistor flyback topology.”

The invention discloses a voltage stabilization control circuit applied to multi-path output flyback topology, which relates to the field of multi-path output auxiliary power supply, and comprises a transformer, a primary side driving switch circuit, a feedback control loop and a plurality of groups of secondary side output loops and load simulation circuits, a load simulation circuit composed of a diode, a capacitor and a resistor is introduced into a key secondary output loop, a feedback sampling point is moved to the capacitor, and the time constant of the load simulation circuit is matched with the load time constant of each output loop through fine design. By means of the design, the controller can be intelligently guided to adjust the duty ratio, it is ensured that under all load conditions, output voltages of all paths can be kept above rated values, system downtime is fundamentally avoided, and the reliability of the system is improved. According to the circuit, the reliability and the load adaptability of the power supply are remarkably improved with extremely low cost.

The invention belongs to the technical field of flyback constant current driving, and relates to a variable load circuit applied to flyback constant current driving and an implementation method of the variable load circuit. The invention aims to solve the technical contradiction that the existing fixed resistor dummy load cannot give consideration to the LED turn-off function, the high full-load efficiency and the low-load power consumption at the same time. The circuit comprises a flyback topology circuit unit and a variable load circuit unit, the variable load circuit automatically switches impedance according to an output voltage: when the output voltage is lower than a threshold value, the impedance is low, excess energy in a turning-off state is efficiently consumed, and stable turning-off of an LED is ensured; when the output voltage is higher than the threshold, high impedance is presented, and invalid power consumption is remarkably reduced. An additional control circuit is not needed, self-adaptive adjustment is achieved through pure hardware logic, compatibility with an existing flyback topology is high, a fixed resistance dummy load can be directly replaced, the LED adjusting and extinguishing function is guaranteed, meanwhile, the driving full-load efficiency is improved, and the no-load power consumption is reduced.

The invention discloses an inverter topology circuit, an inverter and a photovoltaic power generation system. The inverter topology circuit comprises an input circuit, a forward and reverse excitation circuit and an output circuit, the input circuit comprises a photovoltaic panel and a first capacitor, the forward and reverse excitation circuit comprises a first branch circuit, a second branch circuit and a second capacitor; wherein the first branch is connected with the first capacitor in parallel, the second branch is connected with the first branch in parallel, and the second capacitor is connected with the second branch in parallel; the first branch circuit and the second branch circuit are both forward-flyback topological circuits and are alternately conducted; the output circuit comprises a first switch group, a second switch group and an external load; wherein the first switch group is connected with the second capacitor in parallel, the second switch group is connected with the first switch group in parallel, one end of the external load is connected with the first switch group, and the other end of the external load is connected with the second switch group. By adopting a double-transformer structure and an interleaved parallel forward-flyback topological circuit, the power density is increased, ripples are reduced, and the reliability is improved.

The embodiment of the invention discloses a flyback topology circuit and a circuit board, and relates to the field of power circuits. The flyback topology circuit provided by the invention comprises a resonant conversion LLC module, a first rectification filtering module, a first load module, a switching module, a flyback module, a second rectification filtering module, a voltage regulation module and a second load module. Based on the circuit structure provided by the invention, when the voltage value of the first working voltage is greater than the voltage value of the second working voltage, the switching module is switched on to enable the second load module to work based on the first working voltage, or when the voltage value of the first working voltage is smaller than or equal to the voltage value of the second working voltage, the switching module is switched off to enable the second load module to work based on the second working voltage. And the second load module works based on the second working voltage. According to the embodiment of the invention, the power conversion efficiency of the flyback topology circuit can be improved, and the flyback topology circuit is simple in structure.

The utility model relates to the field of audio power supplies, in particular to a double-transistor flyback topology circuit structure of an audio power supply module, which is characterized by comprising a double-transistor flyback switching circuit and a voltage conversion circuit, and the output end of the double-transistor flyback switching circuit is electrically connected with the input end of the voltage conversion circuit. According to the utility model, the output power and efficiency are improved, the peak voltage and the peak current can be effectively controlled, the ripples at the output end can be reduced, and the circuit is especially suitable for equipment sensitive to the ripples.

The utility model discloses a kind of determination circuits of output power of flyback topology structure, comprising: the detection end of synchronous rectification mos pipe SR end is connected to resistance R1 low end, parallel resistance R2 between detection end and resistance R1, detection end includes diode D1 and bias voltage source V B Diode clamping circuit composed of diode D1 and diode D2, triode Q1 and triode Q2 compose low-connection current mirror, triode Q2 connects dynamic voltage;Low-connection current mirror delivers detection current mirror image to resistance R3;Voltage comparator T1 is based on detection current and resistance R3 output detection signal, rising edge counter J1 determines the rising edge frequency of detection signal, output determination result. Thus, only need to add a resistance on existing drive circuit, can be compared by voltage comparator output detection signal containing rising edge and falling edge, according to this determination switching frequency, realize load determination, device demand is greatly reduced, and detection accuracy is greatly improved.

The winding multiplexing soft switching flyback circuit comprises an energy storage unit, a main control unit, a switch unit, a VCC power supply soft switching unit, a sampling unit, a high-frequency transformer unit and a rectification output unit. According to the utility model, the second primary winding of the flyback switching power supply is used as the main power winding, the VCC power supply winding and the soft switching auxiliary winding to supply power to the main control unit and realize the soft switching of the main switch, compared with the conventional flyback topology, the flyback topology circuit can realize the ZVS of the main power tube, and can realize the soft switching of the main switch. Meanwhile, a soft switch auxiliary winding does not need to be added, loss is reduced, transformer primary side framework pins can be effectively reduced, and therefore the size of the transformer is reduced.

A transitional USB receptacle has one USB PD port and one USB-C port (non-PD). The receptacle includes flyback topology for AC / DC conversion, a bypass circuit, a buck converter, and a USB controller that determines the voltage demands of external devices connected to the USB-C and PD ports. The flyback topology uses a transformer with two sets of windings that produce different output voltages. The bypass switch is configured to ensure that only voltage signals under 10V are input to the buck converter, resulting in a different one of the transformer output voltages being input to the buck converter under different load demands. This enables the buck converter to more efficiently produce a 5V at the USB-C port when the USB PD port needs to simultaneously supply either 15V or 20V, and also enables the buck converter to more efficiently produce a 5V or 9V output at the USB PD port.

A motor driving circuit based on pre-charging and multipath flyback power supplies belongs to the field of motor driving, and comprises high-voltage DC input terminals, a pre-charging buffer unit, a multipath isolation power supply conversion unit and a motor driving unit, the pre-charging buffer unit is connected between the input terminals, current-limiting charging is carried out on a bus capacitor through a pre-charging resistor, and the multipath isolation power supply conversion unit is connected with the motor driving unit. The power-on impact current is suppressed; the multi-path isolation power supply conversion unit adopts flyback topology, bus voltage is converted and isolated into multi-path independent low-voltage direct-current power supplies, a closed-loop voltage stabilizing circuit is configured for at least one path of output, and the motor driving unit obtains driving power from a bus capacitor and obtains a control power supply from the multi-path isolation power supplies, so that efficient and reliable driving of a motor is realized; according to the invention, the problems of high-voltage power-on impact and multi-path isolation power supply are solved, and high reliability, high integration and strong anti-interference capability are realized.

The application provides an OTP balance protection circuit, and relates to the field of protection circuits.The OTP balance protection circuit comprises a flyback topology main circuit, a VCC power supply circuit, an OTP protection pin control circuit and an OTP balance control circuit.The utility model discloses a single point detection is realized to many devices balance protection, reduces circuit complexity and cost;the OTP protection point is adaptively adjusted, and the reliability under different input voltages and load conditions is ensured;the insulation problem of cross connection is avoided, and the design is simplified;the OTP function is closed when the load is light, and the risk of false triggering is reduced;the circuit can reliably protect various power devices under different input voltages and different load currents.

The invention discloses an LED backlight driving circuit controlled by an N-type MOSFET. The primary side of a flyback transformer of the driving circuit is connected with a primary side switching tube; a first winding in a secondary side winding of the flyback transformer is connected with a first rectification filter circuit, and the output end of the first rectification filter circuit forms a voltage stabilization output end to supply power to a system mainboard; one end of a second winding in the secondary side winding is connected with the cathode of a protection diode, and the anode of the protection diode is grounded; the drain electrode of the first N-type MOSFET is connected with the other end of the second winding, and the source electrode of the first N-type MOSFET is connected with the positive electrode of the light bar; the grid electrode of the first N-type MOSFET is connected with a grid electrode driving circuit; the power supply end of the PWM control chip is connected with the voltage stabilization output end, the output pin of the PWM control chip is connected with the grid drive circuit, and the feedback pin of the PWM control chip is connected with the current sampling end of the LED light bar. According to the invention, integration of voltage stabilization and constant current output is realized in the single-stage flyback topology.

The utility model discloses a 240W grade electric vehicle program control charger circuit, comprising a low pass filter circuit module, a rectifier bridge, an RCD absorption circuit module, a transformer T1, a diode D4, a relay FJ1, a feedback voltage loop module, a feedback current loop module and the like, the 240W grade electric vehicle program control charger circuit uses a chip U10 as a core to form a flyback topology, uses a PQ3230 transformer to isolate output, and uses a relay FJ1 as a relay FJ1. And the relay controls output, and the feedback loop is matched with the voltage loop and the current loop to control the voltage and the current respectively so as to output the desired voltage and the desired current. Compared with the prior art, the charger has the advantages of being small in heat productivity, high in switching speed and capable of working without a fan, has the functions of over-temperature protection, over-power protection and overvoltage and undervoltage protection, and enables the safety of the charger to be greatly improved.

The invention discloses a wide-voltage input high-efficiency conversion device based on full-bridge or half-bridge resonance forward and reverse excitation topology and a control method, which break through the efficiency and adaptability bottlenecks of the traditional wide-voltage conversion device through dual-transformer forward and reverse excitation mode collaborative switching, resonance network soft switching optimization, magnetic circuit air gap design and adaptive frequency control. The device supports 20V-1000V ultra-wide input voltage, the peak efficiency is greater than or equal to 96.5%, and the device has the advantages of high power density, low loss, strong reliability and the like, and can be widely applied to the fields of industrial power supplies, new energy automobiles, aerospace and the like.

This invention relates to the field of high-voltage power conversion technology, and discloses an 800V high-voltage input dual-transistor flyback auxiliary power supply device. The device includes an input filtering module, a dual-transistor flyback power conversion module, a control and drive module, an output rectification and filtering module, and a protection module. The core of this invention lies in utilizing the clamping characteristics of the dual-transistor flyback topology to precisely limit the voltage stress of the power switching transistors (Q1, Q2) to an 800V input voltage level, thereby achieving a breakthrough by using industrial-grade MOSFETs with a 900V withstand voltage rating, avoiding the need for ultra-high withstand voltage (>1600V) special devices required in single-transistor solutions. Combined with a symmetrical transformer primary winding design, EE-type magnetic core air gap optimization, and an isolated drive scheme, this invention solves the problems of high cost, low efficiency, and complex structure inherent in existing 800V auxiliary power supplies. It features low voltage stress, high conversion efficiency, compact structure, low cost, and high reliability, and can be widely adapted to 800V high-voltage platforms such as new energy vehicles and energy storage systems.

The utility model discloses a winding multiplexing flyback circuit which comprises an energy storage unit, a main control unit, a switch unit, a VCC power supply unit, a sampling unit, a high-frequency transformer unit and a rectification output unit. The second primary winding serves as the main power winding and also serves as the VCC power supply winding to supply power to the main control unit, compared with a conventional flyback topology, one VCC power supply winding can be omitted, the size of a high-frequency transformer framework is reduced, meanwhile, the coil saturation is optimized, and the overall performance of the high-frequency transformer is improved. And meanwhile, the cost of the high-frequency transformer is reduced.

The present application belongs to the technical field of flyback constant current driving, and relates to a variable load circuit applied to flyback constant current driving and an implementation method thereof. The present application aims to solve the technical contradiction that the existing fixed resistance dummy load cannot simultaneously consider the LED dimming function and high full-load efficiency and low no-load power consumption. The circuit comprises a flyback topology circuit unit and a variable load circuit unit. The variable load circuit automatically switches impedance according to the output voltage: when the output voltage is lower than the threshold value, low impedance is presented, the excess energy in the dimming state is efficiently consumed, and the LED is ensured to be stably extinguished; when the output voltage is higher than the threshold value, high impedance is presented, and the invalid power consumption is significantly reduced. Without an additional control circuit, adaptive adjustment is realized through pure hardware logic, the compatibility with the existing flyback topology is high, and the fixed resistance dummy load can be directly replaced, so that the LED dimming function is ensured, the driving full-load efficiency is improved, and the no-load power consumption is reduced.

The application discloses a control method of a switching converter, which sequentially enters a bootstrap capacitor pre-charging stage, a narrow pulse mode low-frequency starting stage, a narrow pulse mode volt-second balance frequency increasing stage and a complementary mode volt-second balance frequency increasing stage before entering a stable working state of a clamped asymmetric half-bridge flyback topology; on the one hand, the main power tube and the secondary rectifier tube can realize full-range zero-voltage switching and zero-current switching in the starting process, greatly improving the problems of large primary voltage and current stress and large secondary voltage stress of the existing clamped asymmetric half-bridge flyback topology during power-on starting; on the other hand, the starting speed of the switching converter can be effectively improved, and the smooth switching of the switching converter from soft-start voltage to loop feedback voltage for controlling the working of the switching converter can be ensured, and the current stress peak of the main power tube and the secondary rectifier tube caused by switching can be reduced; therefore, the safety and reliability of the switching converter can be improved.

The utility model discloses an asymmetric half-bridge flyback cell charging and discharging test system, which relates to the technical field of battery charging and discharging and comprises a bidirectional ACDC module and a bidirectional isolation DCDC module. One end of the bidirectional ACDC module is connected with a power grid, the other end of the bidirectional ACDC module is connected with one end of the bidirectional isolation DCDC module, and the other end of the bidirectional isolation DCDC module is connected with the battery cell; the bidirectional ACDC module is used for realizing bidirectional energy flow between alternating current of a power grid and a direct current bus, and the bidirectional isolation DCDC module adopts an asymmetric half-bridge flyback topology to directly control a battery cell to charge and discharge. According to the utility model, energy is stored by using the resonant capacitor and the transformer through asymmetric half-bridge flyback, energy transmission between the primary and the secondary is realized through the high-frequency power transformer, zero-voltage switching-on and zero-current switching-off of the power switch tube are realized at the same time, switching loss is reduced, and efficiency is improved.

The invention discloses a load balancing control method for an unmanned aerial vehicle battery BMS system, and relates to the technical field of computers, and the method comprises the steps: collecting a multi-source flight state and battery parameters in real time, and carrying out the filtering; dynamically estimating the SOC of each battery cell by fusing an open-circuit voltage method and an ampere-hour integral method, and calculating a consistency deviation; identifying a flight stage based on the lightweight decision tree, and dynamically adjusting a balance trigger threshold; when the conditions are met, single-channel equalization is carried out on the SOC extreme value battery cell through bidirectional flyback topology, and the optimal equalization current is analyzed and solved; meanwhile, closed-loop energy efficiency feedback is introduced, and the driving duty ratio is dynamically adjusted according to a copper loss and iron loss model so as to suppress loss. According to the method, quick response, efficient low-noise balance and whole machine endurance improvement under the high-dynamic working condition are achieved, the SOC consistency convergence time is remarkably shortened, and the balance energy consumption is lower than the preset proportion upper limit of the total discharge energy.

The application discloses a switch tube control method, a controller, a converter and a power adapter. The switch tube control method is used for controlling a first switch tube in a hybrid flyback topology converter. The switch tube control method comprises the following steps: generating a first feedback voltage based on a current flowing through a photocoupler, and determining an operation mode based on the first feedback voltage; outputting a second feedback voltage based on a first difference value between a voltage of an input power supply and a first voltage and the first feedback voltage, so that the same first feedback voltage can be obtained under different input power supplies and output voltages of the hybrid flyback topology converter, wherein the first voltage is a product of a turn ratio of a primary winding and a secondary winding and the output voltage; and controlling the first switch tube to be turned off based on the operation mode and the second feedback voltage. In the foregoing manner, the stability of the corresponding relationship between the first feedback voltage and an output current can be improved, so that debugging and power optimization can be facilitated.