60 results about "Active clamp" patented technology

The invention relates to the technical field of series voltage sharing of power electronic power devices, in particular to a dynamic voltage sharing circuit of a high-voltage integrated gate commutated thyristor (IGCT) series valve group and a control method of the dynamic voltage sharing circuit of the high-voltage IGCT series valve group. The voltage is monitored in real time; the overvoltage energy release unit is used for releasing transient overvoltage energy; all the active clamping circuits are connected in series to form a clamping matrix, corresponding overvoltage energy discharge units are triggered when overvoltage is detected, and transient voltage sharing is optimized by the central controller in combination with an arbitration strategy. By improving the voltage balancing capability between the IGCT device valve group modules, transient overvoltage energy can be quickly sensed and released, the dynamic voltage balancing problem is effectively solved, the system operation stability is improved, meanwhile, the power consumption in the online operation process is remarkably reduced, the size of a heat dissipation system is reduced, and the power density of the converter valve is greatly improved.

The utility model relates to a switching power supply circuit and electronic equipment. The circuit comprises a power supply input end, a power supply output end, a transformer comprising a primary winding and a secondary winding, a main power switch unit, an active clamping unit, a clamping driving unit, a voltage dividing unit and a built-in MOS control chip. The main power switch unit is connected with the power supply input end, the primary winding and the voltage division unit, and is switched on when receiving voltage division output of the voltage division unit; the voltage dividing unit is connected with the power supply input end and the built-in MOS control chip, and generates divided voltage output when the built-in MOS control chip is switched on; the clamping driving unit is connected with the built-in MOS control chip and generates a first driving level when the clamping driving unit is switched on and generates a second driving level when the clamping driving unit is switched off, and the active clamping unit is connected with the primary winding and the clamping driving unit, is switched off when receiving the first driving level and is switched on when receiving the second driving level. According to the utility model, the loop loading capability and the voltage stress bearing capability can be improved through a simple circuit design.

A power converter includes a transformer, a main switch, an active clamp switch, and a primary side controller circuit. The primary side controller circuit is configured to indirectly measure a magnetizing current through the transformer during a first switching cycle of the power converter and estimate a zero-crossing point of the magnetizing current for a second switching cycle based on the indirect primary side measurement of the magnetizing current. Based on the estimated zero-crossing point, the primary side controller circuit generates an auto-tuned delay, for the second switching cycle, between disabling the main switch and enabling the active clamp switch before the zero-crossing of the magnetizing current occurs. The active clamp switch is enabled during the second switching cycle in accordance with the auto-tuned delay.

The invention relates to a converter circuit and electronic equipment. The converter circuit comprises an active clamping circuit, a control circuit and a voltage stabilizing circuit, active devices in the active clamping circuit are controlled through the active clamping circuit to realize soft switching, that is, a first switching tube and a second switching tube are controlled to realize soft switching, so that the conduction loss of the first switching tube and the second switching tube is reduced, and the switching efficiency is improved. The problem that large loss is caused when the PFC converter works at high frequency due to the fact that an existing passive clamping circuit cannot achieve soft switching is solved.

A controlling method of a power converter includes performing a first switch controlling step and a second switch controlling step. The first switch controlling step is performed to control a primary switch of the power converter by a first controlling signal. The second switch controlling step is performed to control an active clamp switch of the power converter by a second controlling signal. The primary switch is turned on by the first controlling signal at each of a plurality of power converter switching cycles. The active clamp switch is not turned on by the second controlling signal at a part of the power converter switching cycles, and the active clamp switch is turned on by the second controlling signal at another part of the power converter switching cycles.

Solid-state circuit breakers (SSCBs) have been witnessing an impressive progress with the aid of wide bandgap (WBG) devices such as silicon carbide (SiC) MOSFETs. Along with obtaining high efficiency as the result of low on-state resistance, response times have been gaining remarkable achievements in microseconds range. Not only that, the reported successes in control and gate drivers design and incorporating fault detection / location techniques in SSCBs are promising. A MOV-resistive capacitive switch (MOV-RCS) snubber for solid state circuit breakers addresses the following: 1) the MOV degradation issue in DCCBs is solved, 2) the maximum allowable DC bus voltage on DCCBs is extended. The solid state circuit breaker and an active clamping snubber includes a first circuit including a fault current bypass based solid state breaker for low voltage direct current systems.

The application provides a controller of an active clamp flyback conversion circuit, a power module and an electronic device. After the active clamp flyback conversion circuit operates in a suspended working state, the controller controls the discharge of a resonance capacitor of the active clamp flyback conversion circuit, so that the voltage value of the output voltage of the power circuit is higher than the preset voltage value of the low-voltage protection of the controller, thereby avoiding the restart of the controller due to the low-voltage protection, and improving the stability of the power module and the electronic device in which the active clamp flyback conversion circuit is located. Moreover, when the controller controls the discharge of the resonance capacitor, the output voltage ripple of the active clamp flyback conversion circuit is not increased, and noise from the input power is not introduced.

The present invention provides a semiconductor device that can reduce the overall surface area of ​​multiple diode elements in a clamp circuit while satisfying the required element breakdown voltage for each individual diode element. [Solution] The semiconductor device includes a chip 2 having a first main surface 3, a p-type first well region 64 formed on the surface of the first main surface 3, and an active clamp circuit interposed between the drain terminal 15 and the gate control circuit. The active clamp circuit includes a plurality of diode elements DS formed on the surface of the first well region 64 in a diode formation region 8 set on the first main surface 3 and connected in series with each other. The plurality of diode elements DS include two first diode elements DS1 and ten second diode elements DS2 whose distance in the first element direction X1 on the outer circumference is shorter than that of the first diode elements DS1. The two first diodes DS1 are connected to the drain terminal 15 side of the ten second diodes DS2.

The application provides a kind of driver protection function test circuit and test method, the test circuit includes: short-circuit protection function test circuit, gate under-voltage protection function test circuit and high-voltage active clamping protection test circuit, wherein, short-circuit protection function test circuit is tested by double-path voltage division between the collector / drain and emitter / source of the driver to be tested, power emitter / source and emitter / source to apply voltage to carry out short-circuit protection function test;Gate under-voltage protection function test circuit is tested by series voltage division to adjust the power supply voltage of the driver to be tested to carry out gate under-voltage protection function test;High-voltage active clamping protection test circuit carries out active clamping protection test by detecting high-voltage DC power output current. By implementing the application, the protection function test of the driver is realized, and the function retest of the driver under the condition of no structural damage before final shipment is solved.

In an example embodiment, a method comprising identifying, by a primary-side controlled Universal Serial Bus Power Delivery (USB-PD) alternating current to direct current (AC-DC) converter, a first pulse, wherein the first pulse is received from a pulse transformer. The method further includes determining that a threshold duration of time is satisfied. In response to determining that the threshold duration of time is satisfied, the method includes identifying a second pulse, wherein the second pulse is received from the pulse transformer. The first pulse and the second pulse are used for control of a high-side field effect transistor (FET) and a low-side FET, where the high-side FET is coupled to an active clamp flyback (ACF) circuit and the low-side FET is coupled to a flyback transformer of the USB-PD AC-DC converter. In response to identifying the second pulse, the method further includes controlling operation of the high-side FET or the low-side FET.

The invention belongs to the technical field of elevator falling prevention, and particularly relates to a self-locking anti-falling elevator which comprises a safety tongs mounting plate, main structures are symmetrically clamped and mounted on the end face of the side, close to the gravity, of the safety tongs mounting plate, an anti-falling structure is arranged on the side, close to the gravity, of each main structure, and a cleaning structure is arranged outside the safety tongs mounting plate; when the brake clearance is abnormal (insufficient compensation or excessive compensation trigger), the driving caliper arm is pulled through the steel wire rope, relative clamping is generated between the brake wedge block in the progressive safety caliper and the guide rail, and no matter whether the brake wedge block fails to brake the guide rail or not, the cable always changes the traction wheel to a set angle range, so that the safety of the safety caliper is ensured. And finally, the elastic floating clamping mechanical chain transmission of the brake clamping plate to the guide rail is realized through whether the Z-section rack is meshed with the brake gear or not, and the limitation of a fixed indexing value is avoided.

The invention relates to the technical field of semiconductors, and discloses a GaN HEMT structure with an active clamping absorption circuit, the GaN HEMT structure comprises a base layer substrate, a base layer buffer layer, a base layer GaN layer and a base layer AlGaN layer, and the GaN HEMT structure further comprises a base layer source electrode, drain electrode metal, a base layer grid electrode, a base layer dielectric layer and a connecting dielectric layer; the active clamping absorption part and the GaN HEMT core structure are efficiently integrated, a potential conduction path is optimized, the instantaneous overvoltage peak generated by the drain electrode in a high-frequency switching scene can be quickly responded, overvoltage energy is efficiently absorbed and discharged, a grid electrode or a drain electrode insulation structure is prevented from being broken down by overvoltage, the working stability of the device is remarkably improved, and the reliability of the device is improved. The core problem that a traditional device is prone to being damaged due to overvoltage is solved.

The invention relates to an SEPIC-ZETA bidirectional DC-DC efficient converter based on improved RCD passive absorption and active clamping. The SEPIC-ZETA bidirectional DC-DC efficient converter comprises a bidirectional DC-DC isolation conversion module, a first-stage RCD clamping absorption unit, a second-stage RCD clamping absorption unit, a third-stage RCD clamping absorption unit and an active clamping circuit module. According to the bidirectional DC-DC high-efficiency converter, stress of a switch tube can be effectively clamped when the SEPIC-ZETA works bidirectionally, meanwhile, energy of leakage inductance is absorbed through the corresponding RCD clamping absorption unit and fed back to a bus to be utilized, and the working efficiency and the dynamic performance of the isolation converter are greatly improved. Through efficiency optimization and the working characteristics of the SEPIC-ZETA circuit, the converter can be better suitable for a DC-DC bidirectional circuit, and PWM closed-loop control is used under the condition that the efficiency of the converter is kept, so that the converter can be better applied to more power supply devices such as an energy storage inverter, a UPS, a server power supply and the like.

The invention relates to an active clamping flyback converter and a control method thereof, and belongs to the field of flyback converters. According to the active clamping flyback converter, voltage stabilization of output voltage is achieved through a double-closed-loop control structure composed of a peak current mode loop and a dead time control loop, and the peak current mode loop is used for controlling the conduction time of a main switching tube. And the dead time control loop is used for detecting whether the active clamping flyback converter realizes a soft switching function or not. A double-loop control loop of a peak current mode and a dead time control mode is adopted, the problem that when the active clamping flyback converter is in light load, zero voltage switching is difficult to achieve in the first switching period, and additional loss is caused is solved, the cost of circuit design is effectively reduced, the occupied size is reduced, and the integration level is improved.

The invention discloses an IGBT (Insulated Gate Bipolar Translator) driving control method based on secondary side hardware protection and active clamping, which comprises the following specific steps of: establishing an IGBT digital twin model, and updating junction temperature distribution, saturation voltage drop and theoretical boundaries of a dynamic safe working area under different working conditions in real time through model simulation; in the normal switching process of the IGBT, voltage waveforms and current change rate waveforms in the switching-on and switching-off stages of the IGBT are collected in real time, key parameters are identified, and meanwhile self-adaptive correction is carried out; according to the invention, the conversion from passive protection to active prediction can be realized, the accuracy of protection criteria is greatly improved, the voltage stress and loss of a device are remarkably reduced, false triggering and misjudgment are reduced, the self-diagnosis capability and response speed of a system are improved, the time precision and coordination of protection decisions are ensured, and the reliability of the system is improved. Thermal fatigue and breakdown risks caused by overstress are reduced, so that the service life of the device is prolonged, and the overall reliability and operation efficiency of the power module are improved.

The application discloses a working mode detection method and circuit of an active clamp flyback converter, a main control chip, samples a drain end voltage VDS of a main power tube QL in a current period, detects a first voltage drop time of the main power tube QL after the main power tube QL is turned off, and determines the working mode of the current period of the active clamp flyback converter by judging the sequence of the first voltage drop time and a clamp tube driving time. Furthermore, based on the working mode determination result, the dead time of the active clamp flyback converter is accurately adjusted to be suitable for the detected working mode, the problem of mismatching between the dead time and the working mode is avoided, the main power tube QL of the active clamp flyback converter can keep realizing soft switching in a full load range, the switching loss of the active clamp flyback converter is greatly reduced, and the efficiency of the converter is improved.

This invention relates to the field of clamping control, and more particularly to an active voltage overshoot clamping system for battery testing equipment. The invention comprises a clamper, a feature memory, a filter, an interference analyzer, a predictor, and a clamping controller. It uses prior data—including the test step execution sequence, time-domain mapped overshoot characteristics, and the attribute characteristics of the tested battery—to filter out overshoot step combinations and construct a drift feature pool specific to each combination. Subsequently, when the test equipment pre-executes the overshoot step combination, the overshoot occurrence is predicted, and a clamping optimization strategy is determined based on the adaptability of the drift feature pool, adjusting the duty cycle upper limit in advance. This invention utilizes prior data to summarize overshoot step combinations and considers the differences in the attributes of the tested battery to construct a drift feature pool. This allows the system to perform clamping control adaptably to the attributes of the tested battery under different overshoot step combinations, improving the accuracy and reliability of overshoot voltage suppression.

This invention belongs to the field of power electrical technology and relates to a wide voltage range clamped boost LLC resonant converter, comprising: an input DC bus voltage unit, an active clamped boost unit, an inverter bridge unit, an LLC resonant tank unit, a transformer T, and a rectification and filtering unit; the active clamped boost unit includes a first feed inductor, a second feed inductor, a clamping capacitor, a third switch S3, and a fourth switch S4; the LLC resonant tank unit includes a resonant inductor and a resonant capacitor connected in series, and a magnetizing inductor of the transformer T; the rectification and filtering unit includes a first rectifier diode, a second rectifier diode, and a filter capacitor C. o Load R L This invention solves the technical problem in the prior art that traditional LLC converters have a limited gain adjustment range and cannot simultaneously meet high boost requirements.

The utility model provides a forward active clamping driving system. A control circuit in the forward active clamping driving system comprises a main switch unit, an active clamping switch unit and an active clamping capacitor. The main control chip comprises a first pin and a plurality of second pins. The control end of the active clamping switch unit is electrically connected with the plurality of second pins through the clamping control circuit, the first end of the active clamping switch unit is electrically connected with the second polar plate of the active clamping capacitor, and the second end of the active clamping switch unit is electrically connected with the grounding end; and the clamping control circuit is used for controlling the active clamping switch unit to be switched on when the forward active clamping driving system is in a shutdown state. Thus, through the clamping control circuit, the active clamping switch unit can still be conducted when the system is in the shutdown state, and the situation that the active clamping switch unit is continuously turned off when the system is in the shutdown state, consequently, an active clamping capacitor is continuously charged, and the reliability of the main switch unit or the active clamping switch unit is affected is avoided.

The invention provides a high-precision output voltage sampling system of a primary side feedback active clamping flyback converter, input signals are a main switch tube switching signal and an auxiliary winding feedback voltage of the primary side feedback active clamping flyback converter, and the high-precision output voltage sampling system mainly comprises a slope generation module, a sampling time judgment module and an output voltage acquisition module; the output signal is a sampling voltage value, and the sampling voltage value is transmitted to the control loop, thereby achieving the closed-loop control of the converter. The slope generation module generates a voltage signal in direct proportion to the change slope of the feedback voltage of the auxiliary winding; the sampling time judgment module determines an output voltage sampling time based on the voltage signal representing the slope; and the output voltage acquisition module acquires an auxiliary winding feedback voltage at an output voltage sampling moment, and transmits the auxiliary winding feedback voltage as an output voltage value to the control loop for closed-loop control. According to the invention, high-precision output voltage sampling of the primary side feedback active clamping flyback converter can be realized.

The invention relates to an active clamping forward topology synchronous rectification driving circuit. The circuit comprises a power transformer, a primary switch tube V1 and an active clamping branch. The primary switch tube V1 is used for converting input direct-current electric energy into high-frequency alternating-current electric energy and transmitting the high-frequency alternating-current electric energy to the secondary through the power transformer; the active clamping branch comprises a clamping switch tube V2 and a clamping capacitor CCLAMP which are connected in series; and the active clamping branch is used for realizing magnetic reset of the power transformer and reducing the voltage stress of the primary switching tube V1. According to the invention, a synchronous rectification driving signal source does not need to be additionally designed, the driving signals of the primary switch tube and the clamping tube of the active clamping forward topology can be directly adopted, the secondary synchronous rectification switch tube of the converter can be driven after isolation and processing, and the design of a signal link is simplified. The direct connection risk of a synchronous rectifier tube in a traditional transformer self-driving scheme can be solved, meanwhile, the driving dead zone is adjustable, and the power conversion efficiency of a converter product is effectively improved.

The invention discloses a half-bridge driving circuit and a switching power supply, and the half-bridge driving circuit comprises two input ends which are respectively used for inputting a first initial PWM wave signal and a second initial PWM wave signal; the mode selection circuit is used for setting the driving mode of the circuit to be a direct or half-bridge driving mode; the logic circuit is used for interlocking the first initial PWM wave signal and the second initial PWM wave signal transmitted by the mode selection circuit when the mode selection circuit is set to be in the half-bridge driving mode, and generating first driving PWM wave signals and second driving PWM wave signals which are complementary and have dead time; the driving chip circuit is used for enhancing the driving capability of the second PWM wave signal and then controlling the lower bridge power tube, and enhancing the driving capability of the first driving PWM wave signal and then controlling the upper bridge power tube; and the active clamping circuit is used for clamping the voltage at the two ends of the power tube when the voltage at the two ends of the turned-off power tube exceeds a set value, and raising the driving voltage of the power tube by controlling the capacitor charging current at the control end of the power tube to be raised. The circuit stability can be improved.

The invention provides an active clamping flyback switching power supply multi-parameter identification method and device, and the method comprises the steps: collecting the output voltage and corresponding component parameters of a switching power supply under different working conditions, and the switching power supply comprises an active clamping flyback switching power supply; processing the output voltage and the component parameters to form training data; an initial model is constructed, the training data is utilized to train the initial model, a target model used for multi-parameter identification is formed, and the initial model comprises an input layer, two convolution pooling layers, a residual multi-head self-attention layer and a full-connection output layer; and processing the output voltage of the switching power supply to be detected to form target data, and calling the target model to process the target data to obtain a multi-parameter identification result about the switching power supply.

This invention discloses an active clamp flyback converter, comprising: a first capacitor; a second capacitor and a first resistor; a first switch, a second switch, and a second resistor; a transformer, including a leakage inductance, a primary winding, a secondary winding, and an auxiliary winding; a first diode and a fourth capacitor; a second diode and a third capacitor; a third resistor and a fourth resistor; and a control circuit, including a drive module and a bus voltage sampling module. The bus voltage sampling module utilizes the characteristic that the voltage value of the auxiliary winding is linearly correlated with the bus voltage when the voltage is negative, and clamps the connection point of the third and fourth resistors, which are connected in series across the auxiliary winding, to -200mV. This converts the auxiliary winding voltage into an IVS current sampled and stored internally in the chip. Combined with the switching timing, the IVS current information is converted into voltage information stored on the capacitor. This invention shifts the sampling of the bus voltage to the lower-voltage auxiliary winding, thereby reducing the resistance value of the voltage divider resistor under the same quiescent current.

The utility model provides a dead time adjusting circuit and an active clamping forward power supply chip, which belong to the technical field of switching power supply control, and comprise a current detection module used for detecting the current flowing through a pin OVLP through the resistance of the pin OVLP to the ground and outputting a digital control logic signal and a mirror current source; the digital control output module is connected with the current detection module and is used for receiving the digital control logic signal and converting the digital control logic signal into a control selection signal so as to determine the selected dead time; the variable current output module is connected with the current detection module and is used for outputting variable current according to the mirror current source so as to provide current required by time delay for the dead zone time selection module; and the dead zone time selection module is connected with the digital control output module and is used for selecting a dead zone time path according to the control selection signal, realizing a time delay function by using the current of the variable current output module, outputting a dead zone time control signal and realizing adjustability of dead zone time.

According to the semiconductor device packaging structure and the electronic equipment provided by the invention, triodes, resistors and the like in an active clamping circuit are packaged in an insulated gate bipolar transistor plastic package body, so that a gate active clamping circuit is integrated in the insulated gate bipolar transistor plastic package body on the premise of not changing the packaging boundary dimension of an original insulated gate bipolar transistor; according to the invention, the oscillation of the grid electrode caused by the Miller effect in the bridge topology structure circuit can be slowed down, and the construction of an external clamping circuit or the operation of other external circuits can be avoided at the same time. The insulated gate bipolar transistor device can be directly applied to the layout of an original printed circuit board.

The application discloses an active clamp flyback converter, which comprises a first capacitor, a second capacitor and a first resistor, a first switch tube, a second switch tube and a second resistor, a transformer comprising a leakage inductance, a primary winding, a secondary winding and an auxiliary winding, a first diode and a fourth capacitor, a second diode and a third capacitor, a first depletion-mode NMOS tube and a third resistor, and a control circuit comprising a driving module and a high-voltage power-on module, wherein the high-voltage power-on module controls the gate end of the first depletion-mode NMOS tube during the chip starting process, obtains energy from a high-voltage switch node, and charges the power supply rail of the control circuit. The high-voltage power-on module realizes safe power-on by limiting the charging current during the power-on process of the control circuit, and the charging circuit is turned off after the power-on of the control circuit is completed, so that the static current of the active clamp flyback converter is reduced, and the efficiency is optimized.

This invention relates to the field of charging and discharging equipment, specifically to a current-feedforward single-stage PFC fast charging converter based on an active clamp flyback circuit. The topology of this invention includes an EMI filter circuit, a rectifier bridge, and a BUS capacitor C. bus Isolated resonant converter, PFC inductor L pfc The output half-wave rectifier circuit; the EMI filter circuit is used to filter out harmonics; the PFC inductor is used to achieve AC input current tracking of voltage; the rectifier bridge provides a return path for the PFC inductor and a connection to the BUS capacitor C. bus The charging of the circuit; the isolated resonant converter is used to achieve primary-secondary side isolation and soft switching of the switching transistor; the isolated resonant converter includes a resonant capacitor C. r Isolation transformer, transformer leakage inductance L r Switches Q1 and Q2, where L r and C r The resonant cavity is formed; the output half-wave rectifier circuit includes an SR transistor located on the secondary side of the isolation transformer and an output capacitor C. o .

This invention discloses a zero-current switching active clamp forward converter and its control method and device, relating to the field of converter technology. The key technical points are: the invention samples the resonant current signal from the secondary side of transformer T1 and combines it with a pulse signal to generate an adaptive on-time signal. Then, based on the adaptive on-time signal, a complementary drive signal with a dead zone is generated to control the on- and off-state of the primary-side main power MOSFET Q1 and the reset MOSFET Q2 in the main power circuit. The pulse signal is used to trigger the operation of the zero-crossing detection control unit, enabling the adaptive on-time signal to dynamically adjust the on-time of the primary-side main power MOSFET Q1. This ensures that the zero-current switching active clamp forward converter achieves zero-current turn-off across the entire load range, reducing the turn-off losses of power devices across the entire load range, improving converter efficiency, reducing harmonics during the switching process, and optimizing the converter's EMI characteristics.

The invention relates to the technical field of rectifiers, and provides an active clamping three-phase high-frequency link matrix rectifier and a pulse width modulation method thereof.The active clamping three-phase high-frequency link matrix rectifier comprises a three-phase alternating-current power supply, an LC input filter, a matrix converter, a high-frequency transformer, an uncontrolled rectifier bridge, an output filter and a load which are connected in sequence; an active clamping circuit is connected in parallel between the uncontrolled rectifier bridge and the output filter; each of the upper and lower bridge arms of each phase of the matrix converter comprises two switching tubes which are reversely connected in series. Based on the topology, the resonance process characteristics of the parasitic capacitance of the secondary side diode and the leakage inductance of the transformer are combined, and the high voltage stress generated by the leakage inductance of the transformer and the oscillation of the parasitic capacitance of the secondary side diode is suppressed by driving the auxiliary switch Saux on the premise of ensuring the output quality.