367 results about "Resonant capacitor" patented technology

A resonant capacitor Crk (k is a natural number of one to n) of each circuit element has one end connected in series to a resonant reactor Lr and a primary winding N1 of a transformer T, and another end connected to the resonant capacitor Crk of another circuit element 10 so that a dimensional multiphase LLC converter having a phase difference of 360° / Pk is constructed by Pk (Pk is an optional natural number) of the circuit elements 10.

A control method and system for a resonant converter. The control method for a resonant converter comprises: in each switching cycle, determining a target power value on the basis of an input power control amount and a compensation amount corresponding to a bridge leg (S101); on the basis of the target power value, an input voltage, circuit parameters of the resonant converter, and the current operating mode of a full-bridge inverter module, determining a target slope control amount corresponding to a counter which corresponds to a switching transistor (S102); determining a comparison threshold on the basis of the target slope control amount, the current count value of the counter which corresponds to the switching transistor, and a DC bias voltage of a resonant capacitor corresponding to the current operating mode, wherein the counter starts counting using the DC bias voltage as an initial value in each switching cycle until the actual voltage of the resonant capacitor is equal to the comparison threshold (S103); and determining a control signal on the basis of the actual voltage of the resonant capacitor and the comparison threshold, and controlling the switching transistor on the basis of the control signal (S104).

The invention is suitable for the technical field of resonant converters, and provides a starting control circuit and a resonant converter. The starting control circuit comprises a feedback module, a comparison selection module and a logical operation module, the comparison selection module is electrically connected with the feedback module and the logical operation module, the feedback module is used for being electrically connected with the output end of a resonant conversion circuit in the resonant converter, and the logical operation module is used for being electrically connected with a driving circuit in the resonant converter. According to the starting control circuit provided by the embodiment of the invention, the resonant capacitor voltage constraint threshold value which is gradually enlarged along with the starting process can be constructed, smooth establishment of resonant capacitor direct current bias is realized, the fluctuation amplitude of the resonant capacitor voltage is limited, the problem that the total bus voltage is applied to the resonant inductor in a traditional scheme is avoided, and the starting control circuit is suitable for a high-voltage power supply. Finally, the resonance current peak value in the starting stage is effectively suppressed, and the impact of current stress on core devices such as a switching tube and a resonance inductor is reduced.

A switching control circuit for use in controlling a resonant flyback power converter generates a first driving signal and a second driving signal. The first driving signal is configured to turn on the first transistor to generate a first current to magnetize a transformer and charge a resonant capacitor. The transformer and charge a resonant capacitor are connected in series. The second driving signal is configured to turn on the second transistor to generate a second current to discharge the resonant capacitor. During a power-on period of the resonant flyback power converter, the second driving signal includes a plurality of short-pulses configured to turn on the second transistor for discharging the resonant capacitor. A pulse-width of the short-pulses of the second driving signal is short to an extent that the second current does not exceed a current limit threshold.

The invention relates to a single-stage AC-DC converter and a control circuit. The single-stage AC-DC converter comprises a filter, an input rectifier, a filter capacitor Cin, a first switch bridge arm, a second switch bridge arm, a capacitor Cb, an inductor Lb, a resonant cavity formed by a resonant inductor Lr and a resonant capacitor Cr, a transformer T, an output rectifier and an output capacitor Co. According to the invention, a traditional two-stage AC-DC converter and a control circuit are simplified. Compared with a single-stage AC-DC converter in the prior art, the problem that the current of a resonant cavity is too large can be solved only by adding one inductor, meanwhile, the control strategy is simple, the frequency range conversion of a switching tube is small, and soft switching of the switching tube is easy to achieve, so that high efficiency is easy to obtain, input current can be corrected to achieve a high power factor, and the power factor is high. And the output voltage ripple is small, and the method has remarkable engineering application value and market prospect.

The invention discloses a three-phase single-stage alternating-current and direct-current converter and a control method and device thereof, which are used for improving the conversion efficiency and the power density of the alternating-current and direct-current converter. The converter comprises a three-phase matrix switch circuit, a resonance circuit, an isolation circuit and a rectification circuit. The three-phase matrix switch circuit is connected with three-phase alternating current and comprises three switch branches which are independently arranged, each switch branch comprises an upper bridge arm and a lower bridge arm, the midpoint of the upper bridge arm and the midpoint of the lower bridge arm in each switch branch are connected with one phase of alternating current input, and each bridge arm comprises a bidirectional switch assembly or two switch assemblies which are reversely connected in series; the resonant circuit comprises a resonant capacitor, a resonant inductor and an excitation inductor which are connected in series, and is connected between the common endpoint of the upper bridge arms and the common endpoint of the lower bridge arms of the three switch branches; one side of the isolation circuit is connected with the resonance circuit, and the other side is connected with the rectification circuit; and the rectification circuit comprises at least two switch assemblies, the input side is connected with the isolation circuit, and the output side is connected with load equipment.

A battery heating circuit, a heating control method, a controller, a battery system and an electric device. The battery heating circuit comprises: a battery, a resonant capacitor and a bridge arm, wherein the battery has a battery inductor; the resonant capacitor is connected in parallel to the battery, such that the resonant capacitor and the battery inductor form an LC parallel resonant circuit; the bridge arm is connected in parallel to the battery; and the bridge arm comprises a first bridge arm switch tube and a second bridge arm switch tube connected in series.

A resonant converter includes an input circuit, a first switch circuit, a resonant circuit, a voltage regulation circuit, a second switch circuit, and an output circuit. The first switch circuit is coupled to the input circuit and includes first switch units. The resonant circuit includes resonant tanks, each resonant tank includes a resonant capacitor and a resonant inductor which are coupled in series, and the resonant inductors are coupled to the output nodes of the first switch units by wye connection. The resonant capacitors are coupled to the primary side of the voltage regulation circuit by the wye connection. The second switch circuit includes second switch units and is coupled to the second switch circuit, and the input nodes of the second switch units are coupled to the secondary side of the voltage regulation circuit by delta connection. By the aforementioned arrangement, ZVS or ZCS is implemented.

A multiphase LLC resonant converter of N phases (N represents an integer equal to or more than two) causes N resonant converters connected in parallel to a direct current power supply to operate with a phase difference of 360° / N. One of the resonant converters includes a lower adjustment inductor connected in parallel with primary windings of the lower conversion circuits. The one of the resonant converters includes an upper adjustment inductor connected in parallel with primary windings of upper conversion circuits. Outputs including high potential output terminals and low potential output terminals of the lower conversion circuits and the upper conversion circuits star connected at neutral points via a second resonant capacitor are connected.

The present disclosure relates to a kind of direct current transformer, direct current transformer includes: transformer circuit, inverter circuit, rectifier circuit and resonance circuit;The direct current side of inverter circuit is connected with direct current input port, the alternating current side of inverter circuit is connected with the primary side of transformer circuit;The alternating current side of rectifier circuit is connected with the secondary side of transformer circuit, the direct current side of rectifier circuit is connected with direct current output port;Resonance circuit includes multiple resonance modules, the alternating current side of inverter circuit is connected with the alternating current side of rectifier circuit through multiple resonance modules and transformer circuit;Resonance module includes first capacitor, resonance module is used to control the input or cut-out of first capacitor.The present disclosure can simulate the voltage outputted when direct current transformer adopts different capacitance resonant capacitor, so as to ensure that direct current transformer does not need to set resonant capacitor, can satisfy the realization condition of resonant soft switching in different working condition scene, and then make the switching device in inverter circuit and rectifier circuit can realize soft switching.

This application provides a wireless power transfer system with dual voltage level output and its switching method to solve the problem that existing WPT systems cannot meet the charging needs of different voltage levels. It includes a transmitting unit and a receiving unit. The transmitting unit includes a DC power supply, a high-frequency inverter, and a transmitting coil circuit connected in sequence. The transmitting coil circuit is connected in sequence to a first transmitting coil, a first primary-side resonant capacitor, a control switch, a second primary-side resonant capacitor, and a second transmitting coil. The other ends of both the first and second transmitting coils are connected to the output terminal of the high-frequency inverter. A switching circuit is also provided between the first and second transmitting coils to cooperate with the control switch to enable the system to switch between dual voltage levels. This application achieves the switching between different voltage levels through the control of the control switch and the switching circuit, thus meeting the charging needs of different voltage levels.

The application relates to a bidirectional output L2C3 resonant converter, which comprises two excitation sources and a resonant cavity, wherein the excitation sources are both half-wave bridge circuits; the resonant cavity comprises a transformer, three capacitors and two inductors; the primary winding of the transformer is connected in parallel with a resonant capacitor C p 1; the same end of the primary winding of the transformer is connected with a resonant capacitor C1 and an inductor L1 in series connection; the other end of the inductor L1 is connected with the connection point of the first excitation source and two switch tubes in series connection; the same end of the secondary winding of the transformer is connected with a resonant capacitor C2; the other end of the resonant capacitor C2 is connected with the connection point of the second excitation source and two switch tubes in series connection; the leakage inductor L g of the secondary winding of the transformer is used as a resonant inductor; the other ends of the same ends of the primary and secondary windings of the transformer are respectively connected with the negative poles of the direct-current power supplies of the corresponding excitation sources. Energy bidirectional transmission and synchronous rectification are realized through a brand-new circuit topology. All active switches can realize soft switching, and the working efficiency is improved. In an open-loop control state, the output current does not change with the change of a load, and the application is suitable for a bidirectional constant current working mode.

A signal-radiation device utilizes a metal portion of a connection port as a wireless antenna, including an equipment-connecting port, a resonant capacitor and a high frequency isolation inductor required under certain circuit conditions; wherein the equipment-connecting port is disposed with a metal portion, and one end of the resonant capacitor is connected to the metal portion, and another end of the resonant capacitor is electrically connected to an antenna pin of a piece of wireless equipment; the metal portion and the resonant capacitor together form an LC resonant circuit. By adjusting shapes of a metal wire connected to the connection port and adjusting the capacitance of the resonant capacitor, the LC resonant circuit has an LC resonant frequency equal to a wireless operating frequency, wireless signals can be radiated through the metal portion of the equipment-connecting port which is suitable for wireless equipment with very-small-sized equipment-connecting port.

A current sensor circuit (1) comprises, for example, a sensing coil (N1) configured to change its inductance with a DC current, a resonant capacitor (C1), a phase-adjusting circuit (10) receiving a feedback signal from the resonant capacitor and outputting a driver signal, a circuit (20) having several switching elements (Q1, Q2) forming a half-bridge or full-bridge circuit, wherein the circuit causes the several switching elements to perform a switching operation according to a pulse period of the driver signal, so that an AC signal is supplied to the sensing coil and the resonant capacitor, a signal converter circuit (40) converting the driver signal output by the phase-adjusting circuit into a sensing signal indicating a change in the DC current, and a sensing terminal (DCSIG) outputting the sensing signal externally.

The invention provides a power-limited resonant converter and converter equipment, and relates to the technical field of electronic circuits. The power-limited resonant converter comprises a primary side circuit, a secondary side circuit, a transformer module and a resonant module, the resonant module comprises at least one resonant capacitor, two ends of each resonant capacitor are reversely connected in parallel with a clamping unit, the clamping units are used for being disconnected when the current of the resonant converter is lower than a preset current, and the resonant converter works in a resonant state. When the current of the resonant converter is not lower than the preset current, the resonant capacitor is conducted and bypassed, and the resonant converter works in a non-resonant state. According to the invention, the voltage of the resonant cavity is limited to the preset value through the clamping units which are reversely connected in parallel, so that the current of the resonant cavity is reduced, the current of a switching tube can be fundamentally prevented from rapidly rising, the primary side current is always in a safe range, a conventional overcurrent protection scheme that primary side driving is blocked by overcurrent of a middle circuit does not need to be adopted, and the reliability of the circuit is improved.

A power conversion circuit includes a transformer, a resonant capacitor, a high-side transistor, a low-side transistor, a current detection circuit, a feedback circuit, and a control circuit. The transformer includes a primary coil connected with the resonant capacitor in series. The high-side transistor and the low-side transistor are coupled to the primary coil. The current detection circuit detects a resonant current flowing through the resonant capacitor to generate a current detection signal. The feedback signal generates a feedback signal based on the output voltage of the power conversion circuit. The control circuit integrates a superposition signal of the current detection signal and a slope compensation signal to generate a first integrated signal, integrates the feedback signal to generate a second integrated signal, and compares the first integrated signal to the second integrated signal to drive the high-side transistor and the low-side transistor.

A switching power supply apparatus includes: a pair of input terminals; a pair of output terminals; a transformer; an inverter circuit including first and second switching devices, first and second rectifying devices as voltage clamping devices, a resonant inductor, and a resonant capacitor; a rectifying and smoothing circuit; a current detector detecting whether a current is flowing through at least one of the first rectifying device or the second rectifying device; and a driver performing switching driving. The resonant capacitor is disposed between a second node and one of a pair of coupling lines. The driver performs switching driving to cause both the first and second switching devices to be set to an OFF state in a case where the current detector detects that a current is flowing through the at least one of the first rectifying device or the second rectifying device.

A power supply device with high output stability includes a voltage divider circuit, a full bridge rectifier, a resonant capacitor, a first transformer, a second transformer, a first switch element, a second switch element, a third switch element, an output stage circuit, and a detection and control circuit. The first switch element selectively couples the second transformer to the first transformer. The second switch element selectively couples the output stage circuit to the first transformer. The third switch element selectively couples the output stage circuit to the second transformer. The detection and control circuit appropriately controls the first switch element, the second switch element, and the third switch element according to a divided voltage from the voltage divider circuit and a capacitive voltage from the resonant capacitor.

A power conversion circuit includes a transformer, a resonant capacitor, a resonant inductor, a high-side transistor, a low-side transistor, and a control circuit. The transformer includes a primary coil and a secondary coil. The primary coil, the resonant capacitor, and the resonant inductor are connected in series between a switch node and a ground. The high-side transistor provides an input voltage to a switch node based on the high-side driving signal. The low-side transistor couples the switch node to the ground based on the low-side transistor. The control circuit operates in a pulse frequency modulation mode to generate the high-side transistor and the low-side transistor with a switch frequency. When the switch frequency exceeds the first threshold, the control circuit switches from the pulse frequency modulation mode to the pulse width modulation mode.

The invention discloses a three-phase staggered four-switch buck-boost integrated LLC (Logical Link Control) DCDC (Direct Current to Direct Current) isolation converter. The converter comprises a transformer based on magnetic integration design and a primary side circuit and a secondary side circuit which are connected with two sides of the transformer, the primary side circuit comprises a three-phase staggered parallel four-switch boost-buck circuit and a three-phase LLC resonant circuit, and each stage of four-switch boost-buck circuit comprises four switch tubes and a preceding-stage inductor. The front two switch tubes are located between the positive electrode and the negative electrode of the direct-current bus and form a front bridge arm, the rear two switch tubes are located between the middle bus and the negative electrode of the direct-current bus and form a rear bridge arm, and the front-stage inductor is connected between the middle point of the front bridge arm and the middle point of the rear bridge arm. The three ends of the three-phase LLC resonant circuit are correspondingly connected with the midpoints of the three rear axle arms respectively; the resonant capacitors of the LLC circuits are in angular connection, and other circuits of the LLC circuits are in star connection; the secondary side circuit is composed of a three-phase interleaved parallel full-wave rectification circuit. The invention has the advantages of wide input, high efficiency, high power density and high switching frequency.

The invention discloses a resonance type high-capacity direct-current change-over switch, a control method and a direct-current power transmission system. The switch comprises a main through-flow branch, a main on-off branch, a high-frequency resonance branch and a voltage-limiting energy consumption branch which are connected in parallel, the main through-flow branch is composed of an SF6 switch, the main on-off branch is composed of a vacuum trigger gap, the high-frequency resonance branch is composed of a resonance inductor, a resonance capacitor and a resonance excitation source which are connected in series, and the resonance excitation source is composed of a forward thyristor group, a reverse thyristor group and a pre-charging capacitor. And the states of the forward thyristor group and the reverse thyristor group are complementary. The functions of long-term through-flow, high-frequency on-off and resonance excitation are realized by different elements such as the SF6 switch, the vacuum trigger gap and the resonance excitation source, so that the rated current level and the resonance frequency are greatly improved, the capacitor consumption is reduced, the limitation of SF6 arc voltage on the conversion current level is broken, and the miniaturization design of the high-capacity direct-current conversion switch is realized.

The invention discloses a power conversion circuit and a control method thereof. The power conversion circuit comprises a transformer, a resonant capacitor, a resonant inductor, an upper bridge transistor, a lower bridge transistor and a control circuit. The transformer comprises a primary coil and a secondary coil. The primary coil, the resonant capacitor and the resonant inductor are connected in series between the switching node and the ground terminal. The upper bridge transistor supplies an input voltage to the switching node based on an upper bridge driving signal. The lower bridge transistor couples the switching node to a ground terminal based on a lower bridge driving signal. The control circuit is operated in a pulse frequency modulation mode to generate an upper bridge driving signal and a lower bridge driving signal at a switching frequency. When the switching frequency exceeds a first threshold value, the control circuit switches from the pulse frequency modulation mode to the pulse width modulation mode.

The invention relates to a modulation method and system for improving test power supply efficiency of a current transformer, and the method comprises the specific steps: building a time domain model based on a primary side resonant capacitor uCr1, a primary side resonant inductive current iLr1 and an excitation inductive current im of an LLC resonant converter, deducing a time domain expression of a single-phase-shift mode of the LLC resonant converter through a time domain analysis method, and calculating the test power supply efficiency of the LLC resonant converter. Calculating a phase shift angle of the LLC resonant converter in a low-frequency light-load working mode by combining a modal time domain equation; when the LLC resonant converter works, the output load and the working frequency of the LLC resonant converter are detected, and the working state of the LLC resonant converter is judged; when the output load of the LLC resonant converter is lower than a light-load threshold value and the working frequency is lower than a low-frequency threshold value, the LLC resonant converter automatically enters a low-frequency light-load operation mode; and when the LLC resonant converter enters the low-frequency light-load operation mode, the size of the phase shift angle is adjusted according to the time domain model, so that the LLC resonant converter is separated from the low-frequency light-load operation mode.

A bidirectional DC / DC converter according to an embodiment of the present invention comprises: a transformer; a primary-side circuit connected to one side of the transformer and including a full-bridge circuit composed of first to fourth switches, a first resonant inductor, a magnetizing inductor, and a first resonant capacitor; and a secondary-side circuit connected to the other side of the transformer and including a full-bridge circuit composed of fifth to eighth switches, a second resonant inductor, a second resonant capacitor, and a third capacitor. In a mode in which power is supplied from the secondary-side circuit to the primary-side circuit among operation modes of the bidirectional DC / DC converter, the sixth switch is set to OFF, the eighth switch is set to ON, and the fifth switch and the seventh switch may be turned ON / OFF according to a first switching frequency.

The resonance power supply circuit is provided with a transformer provided with primary and secondary winding wires, first and second switching elements for applying a rectangular wave voltage to one end of the primary winding wire, a resonance capacitor connected to the other end of the primary winding wire, and a control unit that alternately turns on and off the first and second switching elements. The resonance power supply circuit is further provided with a first output circuit including first and second rectification elements, a first capacitor, an output capacitor, and a backflow prevention rectification element, a second output circuit including third and fourth rectification elements, a second capacitor, the output capacitor, and a third switching element provided between the second capacitor and the output capacitor, and a circuit for providing, as feeding back, voltage information indicating a first voltage of the first capacitor to the control unit.

The utility model discloses an embodiment relates to a kind of push-pull resonant converter and the driving power supply of application this push-pull resonant converter, the push-pull resonant converter includes power supply, it includes power supply anode and power supply cathode;Main transformer, it includes primary winding and secondary winding, the primary winding of main transformer is connected to power supply anode and the source of first switch tube and the source of second switch tube, the secondary winding of main transformer is connected to resonant circuit;First switch tube and second switch tube, it is connected to the primary winding of main transformer, power supply cathode and controller;At least one secondary transformer, the secondary winding of each of the at least one secondary transformer is respectively connected to corresponding load;Resonant circuit, it includes first resonant capacitor and second resonant capacitor, resonant circuit is connected between the secondary winding of main transformer and the primary winding of each of at least one secondary transformer in series;And controller, it is used to control the conduction and turn-off of first switch tube and second switch tube.

The invention relates to a control method for a resonant converter. The control method comprises the following steps: determining a first turn-off threshold range and a first switching frequency of the resonant converter in a current first working mode; detecting an input voltage and an output voltage of the resonant converter to determine a current voltage gain of the resonant converter; determining a second switching frequency of the resonant converter in a second working mode to be switched to based on the current voltage gain and load of the resonant converter; calculating a second turn-off threshold range in a second working mode based on the first turn-off threshold range, the first switching frequency, the capacitance of the resonant capacitor and the second switching frequency; voltage feedback at the two ends of the resonant capacitor is collected in real time, and when the voltage feedback exceeds a first turn-off threshold value range, the turn-off threshold value of the resonant converter is switched to a second turn-off threshold value range, and the resonant converter is switched from the first working mode to the second working mode by enabling corresponding switches in the two-phase bridge arms in the full-bridge conversion circuit.

The invention provides a vertical embedded capacitive coupling type wireless power transmission system, which comprises a direct-current voltage power supply, a full-bridge inverter circuit module, a resonant inductor, a resonant capacitor, a coupler transmitting end, a coupler receiving end, a rectifying circuit module and a filter capacitor, according to the invention, a vertical embedded structure is adopted, the transmitting end and the receiving end of the coupler are respectively embedded into the charging device and the underwater to-be-charged equipment, no extra space is occupied, the size is reduced by more than 30% compared with a traditional PCC structure, and the space requirement of small underwater equipment is met; according to the invention, a vertical alignment design is adopted to reduce the polar plate dislocation influence caused by water disturbance, and a self-coupling path can be ignored and only needs to be matched with mutual coupling parameters by combining an air filling medium and a design of autonomously isolating seawater by equipment, so that the system detuning rate is reduced to below 5%, and the output voltage change rate is only 5%; the change of capacitive coupling is stabilized, the misalignment capability of the receiving pole plate is remarkably reduced, and the system volume is reduced in space structure.

The invention provides a comprehensive compensation method and system for radial dislocation non-contact energy transmission, and the method comprises the steps: constructing a three-dimensional compensation model through recognizing the inductance offset amplitude caused by dislocation, combining with the change of the ratio of input current to load voltage, and dynamically adjusting the resonant capacitance and working frequency according to the recognized dislocation scale, thereby achieving the precise compensation, and achieving the comprehensive compensation of the radial dislocation non-contact energy transmission. Comprising the following steps: S1, detecting an input current and a load voltage value of a transmitting end in real time; s2, according to the change of the load voltage value, identifying a transmission antenna inductance offset caused by radial horizontal position dislocation; s3, calculating the ratio of the inductance offset to the input current, querying a preset compensation calculation matrix according to the ratio and the inductance offset, and determining a corresponding compensation coordinate point; s4, judging a dislocation scale according to the position of the compensation coordinate point in the compensation calculation matrix and executing an adjustment strategy; and S5, calculating a compensated load voltage ratio, and if the load voltage ratio is greater than a second threshold value, feeding back to S1 for iterative optimization until the load voltage ratio is less than or equal to the second threshold value.

The circuits and methods of the present disclosure control the active off-time (high side switch on-time) to ensure the magnetization energy release and resonant capacitor energy release in an asymmetrical half-bridge (AHB) converter finish at the same time and all the stored energy is delivered to the output in each switching cycle. Multiple, parallel, techniques to control the high side switch on-time are illustrated. One is to track the volt-seconds applied during the storage cycle and allow the active release off-time to be limited to the same volt-seconds. A second option is to provide a high side switch on-time that is proportional to the on-time of the low side switch in that switching cycle. A third option is to provide a maximum high side switch on-time that can be programmed to ensure the high side on-time is equal to or smaller than half of the resonant period.