Voltage transformation circuit, charging circuit, power adapter, power module and electronic equipment

Abstract

The invention relates to a voltage transformation circuit, a charging circuit, a power adapter, a power module and electronic equipment. The voltage transformation circuit comprises an input end and an output end, each resonant transformation circuit in the plurality of resonant transformation circuits comprises a primary end, a secondary end, a resonant circuit and an output circuit; the plurality of resonant circuits are connected in series and then connected with the input end, and voltage provided by the input end is input to the primary end; and a plurality of output circuits included in the plurality of resonant transformation circuits are connected with the output end after being connected in parallel, and the plurality of output circuits are used for boosting the voltage output by the secondary end and balancing the current output by different secondary ends. According to the resonant transformation circuit, the resonant circuits of the plurality of resonant transformation circuits are connected in series, the output circuits are connected in parallel, and current sharing and voltage boosting among multiple phases are realized through the output circuits, so that the voltage stress of circuit elements is reduced, the output gain of the transformation circuit is improved, and the application requirement in a high-power scene is met.

Description

Technical Field

[0001] This disclosure relates to the field of power supply and charging technology, and in particular to a transformer circuit, a charging circuit, a power adapter, a power module, and an electronic device. Background Technology

[0002] With the technological advancements in new energy batteries, research and development of renewable energy sources such as solar cells and fuel cells are in full swing. Since the output voltage of renewable energy sources like solar cells and fuel cells is typically low, ranging from 20 to 50V, while the power grid generally operates at 400V DC, a boost converter with a high boost ratio is required to step up the voltage when inputting electrical energy from these sources into the grid system.

[0003] Among them, the inductor-inductor-capacitor (LLC) architecture technology is relatively mature in boost converters and is widely used in power supplies ranging from hundreds of watts to thousands of watts. However, due to the influence of its circuit architecture and frequency modulation control, the LLC architecture has a small gain range, which cannot meet the requirements of things like new energy batteries being input into the grid system. Summary of the Invention

[0004] To overcome the problems existing in related technologies, this disclosure provides a transformer circuit, a charging circuit, a power adapter, a power module, and an electronic device.

[0005] According to a first aspect of the present disclosure, a transformer circuit is provided, the transformer circuit comprising: an input terminal and an output terminal; a plurality of resonant transformer circuits, each of the plurality of resonant transformer circuits comprising a primary terminal, a secondary terminal, a resonant circuit, and an output circuit; wherein, the plurality of resonant circuits included in the plurality of resonant transformer circuits are connected in series with each other and connected to the input terminal, thereby inputting the voltage provided by the input terminal to the primary terminal; the plurality of output circuits included in the plurality of resonant transformer circuits are connected in parallel with each other and connected to the output terminal, the plurality of output circuits being used to boost the voltage output by the secondary terminal and to balance the current output by different secondary terminals, wherein the different secondary terminals are secondary terminals in different resonant transformer circuits.

[0006] In some embodiments, the output circuit includes: a voltage doubler rectifier circuit connected between the secondary terminal and the output terminal; and a current sharing element connected across the plurality of voltage doubler rectifier circuits in the plurality of resonant transformer circuits and the output terminal.

[0007] In some embodiments, the current sharing element is a capacitor; wherein the transformer circuit includes a first state and a second state; when the transformer circuit is in the first state, a portion of the plurality of resonant transformer circuits charges the current sharing element; when the transformer circuit is in the second state, another portion of the plurality of resonant transformer circuits, together with the current sharing element, outputs current to the output terminal.

[0008] In some embodiments, the number of current sharing elements is N-1, where N is the number of resonant transformer circuits.

[0009] In some embodiments, the voltage doubler rectifier circuit includes: a boost capacitor, one end of which is connected to the secondary terminal and the other end of which is connected to the output terminal; and a rectifier diode, the negative terminal of which is connected to the boost capacitor and the output terminal, and the positive terminal of which is grounded.

[0010] In some embodiments, the transformer circuit further includes a protection circuit disposed between the resonant circuit and the input terminal. When the current of the resonant circuit is greater than a threshold, the protection circuit disconnects the connection between the input terminal and the resonant circuit.

[0011] In some embodiments, the resonant circuit includes a resonant capacitor disposed between the input terminal and the primary terminal; the protection circuit includes a clamping diode connected in parallel with the resonant capacitor, the clamping diode being used to limit the voltage of the resonant capacitor to be less than or equal to a first threshold voltage.

[0012] In some embodiments, the transformer circuit further includes: a voltage divider capacitor connected in parallel with the input terminal and in parallel with the protection circuit; wherein the first threshold voltage is the voltage of the voltage divider capacitor.

[0013] In some embodiments, the resonant capacitor includes a first resonant capacitor and a second resonant capacitor connected in series; one end of the first resonant capacitor is connected to the positive terminal of the input terminal, the voltage divider capacitor, and the transformer circuit, and the other end of the first resonant capacitor is connected to the second resonant capacitor and the transformer circuit; one end of the second resonant capacitor is connected to the first resonant capacitor and the transformer circuit, and the other end of the second resonant capacitor is connected to the voltage divider capacitor and the transformer circuit; the protection circuit includes a first clamping diode and a second clamping diode; the first clamping diode is connected in parallel with the first resonant capacitor, and the negative terminal of the first clamping diode is connected to the voltage divider capacitor; the second clamping diode is connected in parallel with the second resonant capacitor, and the positive terminal of the second clamping diode is connected to the voltage divider capacitor.

[0014] In some embodiments, the resonant circuit includes: a switch group disposed between the transformer circuit and the input terminal; the number of switch groups is multiple, and each switch group corresponds to a resonant transformer circuit, wherein the switch group controls the multiple resonant transformer circuits to alternately output current to the output terminal.

[0015] In some embodiments, the primary terminal includes a magnetizing inductor and a primary coil; the resonant circuit includes a resonant inductor, one end of which is electrically connected to the magnetizing inductor and the primary coil, and the other end of which is electrically connected to the input terminal; one end of the resonant capacitor is electrically connected to the resonant inductor, and the other end of which is electrically connected to the input terminal, wherein the magnetizing inductor, the resonant inductor, and the resonant capacitor constitute an inductor-inductor-capacitor resonant circuit.

[0016] In some embodiments, the transformer circuit includes an output capacitor disposed between the output circuit and the output terminal, and the output capacitor is connected in parallel with the output terminal. The transformer circuit includes a first state and a second state. When the transformer circuit is in the first state, the output capacitor outputs current to the output terminal. When the transformer circuit is in the second state, the secondary terminal charges the output capacitor through the output circuit.

[0017] According to a second aspect of the present disclosure, a charging circuit is provided, the charging circuit comprising: the transformer circuit described in any of the first aspects.

[0018] In some embodiments, the charging circuit includes a rectifier circuit connected to the output terminal of the transformer circuit; the rectifier circuit is used to convert the direct current output by the transformer circuit into alternating current.

[0019] According to a third aspect of the present disclosure, a power adapter is provided, the power adapter comprising: a transformer circuit as described in any of the first aspects, or a charging circuit as described in any of the second aspects.

[0020] According to a fourth aspect of the present disclosure, a power module is provided, the power module comprising: a transformer circuit as described in any of the first aspects, or a charging circuit as described in any of the second aspects.

[0021] According to a fifth aspect of the present disclosure, an electronic device is provided, the electronic device comprising: a charging module, wherein the charging parameters of the charging module for charging the electronic device are matched with the charging parameters output by the charging circuit according to any one of the second aspects.

[0022] The technical solutions provided by the embodiments of this disclosure can include the following beneficial effects: This disclosure connects the resonant circuits of multiple resonant transformer circuits in series and the output circuits in parallel, and realizes the voltage boost of the transformer circuit and the current sharing among multiple phases through the output circuit, thereby reducing the voltage stress of the circuit components, improving the output gain of the transformer circuit, avoiding damage to the circuit components caused by excessive single-phase current, and meeting the application requirements of high-power scenarios.

[0023] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0025] Figure 1 This is a schematic diagram of a transformer circuit according to an exemplary embodiment.

[0026] Figure 2 This is a current schematic diagram of a transformer circuit in a first state, according to an exemplary embodiment.

[0027] Figure 3 This is a current schematic diagram of a transformer circuit in a second state, according to an exemplary embodiment.

[0028] Figure 4 This is a current schematic diagram of a transformer circuit in a third state, according to an exemplary embodiment.

[0029] Figure 5 This is a current schematic diagram of a transformer circuit in a fourth state, according to an exemplary embodiment. Detailed Implementation

[0030] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0031] In related technologies, multiphase LLC circuits are often used as voltage converters to achieve high-power voltage transformation. However, this approach requires individual control of each phase to achieve current sharing between different phases and prevent current concentration in one phase, which could damage the circuit. However, the control system is complex and difficult to tune, and as the number of phases increases, the number of control chips and auxiliary circuits also needs to be increased, which increases the cost of the transformer circuit.

[0032] To address the aforementioned technical problems, an embodiment of this disclosure provides a transformer circuit, comprising: an input terminal and an output terminal; and multiple resonant transformer circuits, each of which includes a primary terminal, a secondary terminal, a resonant circuit, and an output circuit. The multiple resonant circuits are connected in series with each other and then connected to the input terminal, inputting the voltage provided by the input terminal to the primary terminal. The multiple output circuits are connected in parallel with each other and then connected to the output terminal. These output circuits are used to boost the voltage output from the secondary terminal and to balance the current output from different secondary terminals, where the different secondary terminals are secondary terminals in different resonant transformer circuits.

[0033] This disclosure achieves voltage boosting and current sharing among multiple phases by connecting the resonant circuits of multiple resonant transformer circuits in series and the output circuits in parallel. This reduces voltage stress on circuit components, increases the output gain of the transformer circuit, avoids damage to circuit components caused by excessive single-phase current, and meets the application requirements of high-power scenarios.

[0034] It is understood that the transformer circuit disclosed herein can be used for voltage transformation during the charging process of a charging power supply, and can also be used for voltage transformation during the power supply process to the grid.

[0035] It is understood that the power adapter disclosed herein can be used to charge any of the following devices.

[0036] It is understood that the device to be charged involved in this disclosure is a device with a charging power source. For example, the device to be charged can be a handheld device with wireless connectivity, an in-vehicle device, etc. Currently, some examples of devices to be charged include: smartphones (mobile phones), pocket personal computers (PPCs), handheld computers, personal digital assistants (PDAs), laptops, tablets, wearable devices, in-vehicle devices, or motor vehicles with a charging power source, etc. In addition, when it is a vehicle-to-everything (V2X) communication system, the terminal device can also be an in-vehicle device. It should be understood that the embodiments of this disclosure do not limit the specific technology or specific device form used in the device to be charged.

[0037] Figure 1 This is a schematic diagram of a transformer circuit according to an exemplary embodiment.

[0038] In some embodiments, such as Figure 1 As shown, the transformer circuit may include: an input terminal Vin, an output terminal Vout, and multiple resonant transformer circuits. By using multiple resonant transformer circuits, the output gain of the transformer circuit can be increased, and the adaptable output range of the transformer circuit can be expanded. For example, the resonant transformer circuit may include a first resonant transformer circuit and a second resonant transformer circuit.

[0039] Current can flow into the transformer circuit from the input terminal Vin and then flow out of the transformer circuit from the output terminal Vout.

[0040] Each resonant transformer circuit may include a transformer module, a resonant circuit, and an output circuit.

[0041] A transformer module may include a primary terminal and a secondary terminal. The primary terminal is electrically connected to the input terminal Vin, and the secondary terminal is electrically connected to the output terminal Vout. The transformer module can change the current flowing from the input terminal Vin through the primary terminal, generate an induced current in the secondary terminal, and change the voltage generated in the secondary terminal according to the turns ratio of the primary and secondary terminals of the transformer module. For example, a first resonant transformer circuit may include a first transformer module 11, which may include a first primary terminal T1 and a first secondary terminal T2. A second resonant transformer circuit may include a second transformer module 21, which may include a second primary terminal T3 and a second secondary terminal T4.

[0042] A resonant circuit can be positioned between the primary terminal and the input terminal Vin. The resonant circuit enables the transformer circuit to output a high-frequency resonant current, thereby increasing the output power of the transformer circuit. For example, the first resonant transformer circuit may include a first resonant circuit 10, and the second resonant transformer circuit may include a second resonant circuit 20.

[0043] The output circuit can be set between the secondary terminal and the output terminal Vout. Multiple output circuits can be used to boost the voltage output from the secondary terminal, and multiple output circuits can also be used to balance the current output from the secondary terminal in different resonant transformer circuits and output the current to the output terminal Vout.

[0044] In this system, multiple resonant transformer circuits are connected in series with each other and then connected to the input terminal Vin, so that the voltage provided by the input terminal Vin is input to the primary terminal. Multiple output circuits are connected in parallel with each other and then connected to the output terminal Vout. By making the transformer circuits form an architecture of series input and parallel output, the voltage stress of a single resonant transformer circuit is reduced.

[0045] By connecting the resonant circuits of multiple resonant transformer circuits in series and the output circuits in parallel, the voltage of the transformer circuit and the current sharing among multiple phases are achieved through the output circuits. This reduces the voltage stress on the circuit components, increases the output gain of the transformer circuit, avoids damage to the circuit components caused by excessive single-phase current, and meets the application requirements of high-power scenarios.

[0046] In some embodiments, such as Figure 1 As shown, the output circuit may include: a voltage doubler rectifier circuit and a current sharing element Cf. For example, as... Figure 1 As shown, the first resonant transformer circuit may include a first voltage doubler rectifier circuit 12, and the second resonant transformer circuit may include a second voltage doubler rectifier circuit 22.

[0047] The voltage doubler rectifier circuit is connected between the secondary terminal and the output terminal Vout. Through the charging and discharging process of the capacitor and the rectification and guiding effect of the diode, the voltage doubler rectifier circuit can gradually increase the input low voltage and finally output a high voltage, thereby improving the voltage gain effect of the transformer circuit.

[0048] The current sharing element Cf can bridge multiple voltage multiplier rectifier circuits and the output terminal Vout in multiple resonant transformer circuits. The current sharing element Cf can balance the current in multiple resonant transformer circuits, thereby avoiding excessive current in a single resonant edge circuit and extending the life of circuit components.

[0049] In some embodiments, such as Figure 1 As shown, the current sharing element Cf can be a capacitor, that is, the current sharing element Cf can be a flying capacitor.

[0050] The transformer circuit may include a first state and a second state. When the transformer circuit is in the first state, a portion of the multiple resonant transformer circuits charges the current sharing element Cf.

[0051] When the transformer circuit is in the second state, another part of the multiple resonant transformer circuits, together with the current sharing element Cf, outputs current to the output terminal Vout.

[0052] Since multiple resonant transformer circuits both flow through the current-sharing element Cf in the two states of the transformer circuit, according to the law of conservation of charge of capacitors, the current-sharing element Cf can automatically balance the current of multiple resonant transformer circuits, thus eliminating the need for control devices for current balancing. This reduces the design cost of the transformer circuit while balancing the current in multiple resonant transformer circuits, thereby preventing excessive current in a single resonant edge circuit and extending the life of circuit components.

[0053] In some embodiments, the number of current sharing elements Cf is N-1, where N is the number of resonant transformer circuits.

[0054] For example, when there are two resonant transformer modules, the number of current sharing elements Cf can be one; when there are four resonant transformer modules, the number of current sharing elements Cf can be three. Each current sharing element Cf can balance the current of the two resonant transformer circuits, thereby ensuring the current sharing effect of the current sharing element Cf.

[0055] In some embodiments, such as Figure 1 As shown, a voltage doubler rectifier circuit may include a boosting capacitor and a rectifier diode. For example, the first voltage doubler rectifier circuit 12 may include a first boosting capacitor CbA and a first diode D1, and the second voltage doubler rectifier circuit 22 may include a second boosting capacitor CbB and a third diode D3.

[0056] The boosting capacitor has one end connected to the secondary side and the other end connected to the output terminal Vout. When the boosting capacitor is fully discharged, it can charge itself through the secondary side. When the boosting capacitor is fully charged, it can charge other capacitors together with the secondary side or supply power to the transformer output source together with other capacitors.

[0057] For example, when the current sharing element Cf is a flying capacitor, the boosting capacitor can charge the flying capacitor together with the secondary side or supply power to the transformer output source together with the flying capacitor. The voltage output by the secondary side can be U, and the voltage of the boosting capacitor after charging can be U. When the fully charged boosting capacitor and the secondary side charge the flying capacitor together, the voltage of the flying capacitor can be 2U.

[0058] The rectifier diode has its negative terminal connected to the boost capacitor and the output terminal Vout, while its positive terminal is grounded.

[0059] By arranging the rectifier diodes, the current can travel along a specific path under the constraints of the diodes and the voltage difference, thus forming different equivalent circuits. This allows the same capacitor to be charged or discharged separately in different states of the transformer circuit, thereby fulfilling the functional design of a voltage doubler rectifier circuit.

[0060] In some embodiments, such as Figure 1 As shown, the transformer circuit may also include a protection circuit, which can be set between the resonant circuit and the input terminal Vin. When the current of the resonant circuit is greater than the threshold, the protection circuit can disconnect the connection between the input terminal Vin and the resonant circuit, thereby stopping the transformer circuit from working and preventing excessive current or voltage from damaging the circuit components of the transformer circuit, thus protecting the transformer circuit.

[0061] In some embodiments, such as Figure 1 As shown, the resonant circuit may include a resonant capacitor, which can be used to bring the resonant circuit into a resonant state. The resonant capacitor is located between the input terminal Vin and the primary terminal.

[0062] The protection circuit may include a clamping diode, which may be connected in parallel with the resonant capacitor. The clamping diode may be used to limit the voltage of the resonant capacitor to be less than or equal to a first threshold voltage. For example, when the voltage of the resonant capacitor is greater than the first threshold voltage, the clamping diode may start to conduct and bypass the resonant capacitor, thereby stopping the resonance of the resonant circuit and preventing the energy from the primary terminal of the transformer module from being transferred to the secondary terminal of the transformer module.

[0063] The clamping diode also limits the resonant current, thereby protecting the circuit components of the transformer circuit and providing protection for the transformer circuit.

[0064] Because the transformer circuit with the boost function has a high gain ratio, when the power of the charging circuit is too high, it can make the voltage of the resonant capacitor reach the first threshold voltage and turn on the clamping diode, thereby realizing the automatic conduction of the clamping diode in the event of overpower in the charging circuit.

[0065] In some embodiments, such as Figure 1 As shown, the transformer circuit may further include: a voltage divider capacitor, which can be connected in parallel with the input terminal Vin and in parallel with the protection circuit; wherein, the first threshold voltage is the voltage of the voltage divider capacitor. The voltage divider capacitor can be used to filter noise and pulses in the input current, stabilize the voltage, reduce the voltage stress on other circuit components of the transformer circuit, reduce the withstand voltage requirements of the circuit components, thereby reducing the cost of the transformer circuit.

[0066] Furthermore, the clamping diode can use the voltage of the voltage divider capacitor as a reference to limit the voltage of the resonant capacitor.

[0067] For example, the voltage divider capacitor may include a first voltage divider capacitor CA and a second voltage divider capacitor CB.

[0068] In some embodiments, such as Figure 1 As shown, the resonant capacitor can include a first resonant capacitor and a second resonant capacitor connected in series. One end of the first resonant capacitor is connected to the positive terminal of the input Vin, the voltage divider capacitor, and the transformer circuit; the other end of the first resonant capacitor is connected to the second resonant capacitor and the transformer circuit. One end of the second resonant capacitor is connected to the first resonant capacitor and the transformer circuit; the other end of the second resonant capacitor is connected to the voltage divider capacitor and the transformer circuit. By configuring multiple resonant capacitors, the capacitance value of the first and second resonant capacitors as a whole can be made more accurate, which facilitates the parameter design of the transformer circuit.

[0069] The protection circuit may include a first clamping diode and a second clamping diode. The first clamping diode is connected in parallel with the first resonant capacitor, and the cathode of the first clamping diode is connected to the voltage dividing capacitor; the second clamping diode is connected in parallel with the second resonant capacitor, and the anode of the second clamping diode is connected to the voltage dividing capacitor.

[0070] For example, the first resonant transformer circuit may include a first capacitor C1, a second capacitor C2, a first clamping diode DAH and a second clamping diode DAL, and the second resonant transformer circuit may include a third capacitor C3, a fourth capacitor C4, a third clamping diode DBH and a fourth clamping diode DBL.

[0071] In some embodiments, such as Figure 1 As shown, the resonant circuit may include: a switch group, which is set between the transformer circuit and the input terminal Vin, and there are multiple switch groups, with each switch group corresponding to a resonant transformer circuit. The switch group can control multiple resonant transformer circuits to alternately output current to the output terminal Vout, thereby making the current output of the transformer circuit stable within one cycle, so that the transformer circuit can work normally.

[0072] For example, the first resonant transformer circuit may include a first switch QAH and a second switch QAL, and the second resonant transformer circuit may include a third switch QBH and a fourth switch QBL.

[0073] In some embodiments, such as Figure 1 As shown, the primary terminal may include a magnetizing inductor and a primary coil;

[0074] A resonant circuit may include a resonant inductor, one end of which is electrically connected to the magnetizing inductor and the primary coil, and the other end of which is electrically connected to the input terminal Vin.

[0075] One end of the resonant capacitor is electrically connected to the resonant inductor, and the other end of the resonant capacitor is electrically connected to the input terminal Vin.

[0076] The magnetizing inductor, resonant inductor, and resonant capacitor together form an inductor-inductor-capacitor resonant circuit.

[0077] The resonant inductor, resonant capacitor, and magnetizing inductor can form different resonant frequencies depending on the operating mode. Compared with series resonant converters, the magnetizing inductance and leakage inductance of resonant converters can be utilized, thus significantly reducing the occupied size.

[0078] Furthermore, due to the presence of the inductor-inductor-capacitor resonant module, the switch located between the input terminal Vin and the primary terminal can be turned on and off at zero voltage.

[0079] For example, the first resonant transformer circuit may include a first resonant inductor LrA and a first magnetizing inductor LmA, and the second resonant transformer circuit may include a second resonant inductor LrB and a second magnetizing inductor LmB.

[0080] In some embodiments, when the resonant frequency of the inductor-inductor-capacitor resonant circuit is equal to the switching frequency, the second resonant capacitor can form an inductor-inductor-capacitor resonant circuit together with the resonant inductor and the magnetizing inductor.

[0081] When the resonant frequency of the inductor-inductor-capacitor resonant circuit is not equal to the switching frequency, the first resonant capacitor can supplement the inductor-inductor-capacitor resonant circuit with electrical energy and participate in the circuit resonance together with the second resonant capacitor, thereby ensuring that the resonant circuit can work normally.

[0082] In some embodiments, such as Figure 1 As shown, the transformer circuit may include an output capacitor Cout, which is located between the output circuit and the output terminal Vout, and is connected in parallel with the output terminal Vout. The output capacitor Cout, together with the secondary side, can supply power to the transformer output source. The output capacitor Cout can be used to boost the output voltage, stabilize the output voltage, and stabilize the current waveform output by the transformer circuit.

[0083] The transformer circuit may include a first state and a second state.

[0084] When the transformer circuit is in the first state, the output capacitor Cout can be fully charged, and the output capacitor Cout outputs current to the output terminal Vout. When the transformer circuit is in the second state, the output capacitor Cout can be fully discharged, and the secondary side can charge the output capacitor Cout through the output circuit.

[0085] In some embodiments, the transformer circuit further includes a second diode D2 and a fourth diode D4 connected in series. One end of the current sharing element Cf can be connected between the second diode D2 and the fourth diode D4. Through the rectification effect of the second diode D2 and the fourth diode D4, the current of the flyaway capacitor and the output capacitor Cout can be prevented from flowing back to the output circuit in reverse.

[0086] Figure 2 This is a current schematic diagram of a transformer circuit in a first state, according to an exemplary embodiment. Figure 3 This is a current schematic diagram of a transformer circuit in a second state, according to an exemplary embodiment.

[0087] In some embodiments, such as Figure 1-3 As shown, the transformer circuit may include a first state and a second state, and the resonant transformer circuit may include a first resonant transformer circuit and a second resonant transformer circuit.

[0088] In the first state, the first switch QAH and the fourth switch QBL can be turned on, and the second switch QAL and the third switch QBH can be turned off. At this time, the first voltage doubler rectifier circuit 12 of the first resonant transformer circuit can charge the current sharing element Cf, which is a flying capacitor, and the output capacitor Cout can supply power to the output terminal Vout. The second resonant transformer circuit can charge the first boost capacitor CbA.

[0089] In the second state, the first switch QAH and the fourth switch QBL can be disconnected, and the second switch QAL and the third switch QBH can be turned on. At this time, the second voltage doubler rectifier circuit 22 of the second resonant transformer circuit can be connected in series with the current sharing element Cf, which is a flying capacitor, to charge the output capacitor Cout together. The first resonant transformer circuit can charge the second boost capacitor CbB.

[0090] Figure 4 This is a current schematic diagram of a transformer circuit in a third state, according to an exemplary embodiment. Figure 5 This is a current schematic diagram of a transformer circuit in a fourth state, according to an exemplary embodiment.

[0091] In some embodiments, such as Figure 4 and Figure 5 As shown, when the voltage of the resonant capacitor exceeds the first threshold voltage, the clamping diode connected in parallel with the corresponding resonant capacitor can be turned on, so that the resonant capacitor is bypassed, the resonant circuit stops working, and prevents energy from being transferred from the primary end of the transformer module to the secondary end.

[0092] For example, when the voltage of the resonant capacitor of the first resonant transformer circuit exceeds the first threshold voltage, the transformer circuit can be in the third state; when the voltage of the resonant capacitor of the second resonant transformer circuit exceeds the first threshold voltage, the transformer circuit can be in the fourth state.

[0093] For example, when the voltage of the first capacitor C1 exceeds the first threshold voltage, the first clamping diode DAH can be turned on, so that the first capacitor C1 is bypassed by the first clamping diode DAH. When the first resonant capacitor of the first resonant circuit 10 is bypassed, the first resonant circuit 10 stops working, so that the energy of the first primary terminal T1 of the first transformer module 11 cannot be transferred to the first secondary terminal T2, thus realizing the over-power limiting function.

[0094] The maximum power limit can be obtained using the following two formulas:

[0095] ① Pmax=(C1*Vin*Vin) / Ts

[0096] ② Ts=1 / (2 * Pi * Sqrt(Lr*(C1+C2))

[0097] Pmax is the maximum power limit;

[0098] C1 is the capacitance value of the first capacitor;

[0099] C2 is the capacitance value of the second capacitor;

[0100] Vin is the voltage at the input terminal;

[0101] Ts is the switching period;

[0102] Pi is the mathematical constant π.

[0103] Lr is the inductance value of the resonant inductor.

[0104] Based on the same concept, embodiments of this disclosure also provide a charging circuit.

[0105] In some embodiments, the charging circuit may include a rectifier circuit and a transformer circuit. The input terminal of the rectifier circuit may be connected to the output terminal Vout of the transformer circuit, and the output terminal of the rectifier circuit may be connected to the power grid. The rectifier circuit can be used to convert direct current into alternating current so that the current can be fed into the power grid.

[0106] Based on the same concept, this disclosure also provides a power adapter. A power adapter can be a device used to convert external power to meet the charging parameter requirements of the device being charged.

[0107] The device to be charged can be a laptop, desktop computer, mobile phone, digital broadcasting terminal, messaging device, game console, tablet, medical device, fitness equipment, personal digital assistant, translator, watch, bracelet, or a vehicle with a charging power source, etc.; it can be any type of device with a charging power source. In the following description, a mobile phone is used as an example, but this disclosure is not limited to this.

[0108] In some embodiments, the power adapter may include a charging circuit that can convert the current and voltage of an external power source into current and voltage that meet the charging parameter requirements of the device to be charged.

[0109] In some embodiments, the power adapter may include only a transformer circuit to adapt to a DC power supply.

[0110] Based on the same concept, embodiments of this disclosure also provide a power module. A power module can be a device that converts other forms of energy into electrical energy and provides that electrical energy.

[0111] The power module can be a power bank, a rechargeable battery built into an electronic device, a storage battery, a fixed charging station, etc., and can be a device with charging functionality. In the following description, a power bank is used as an example, but this disclosure is not limited to this.

[0112] In some embodiments, the power module may include a charging circuit that can convert the current and voltage of an external power source into current and voltage that meet the charging parameter requirements of the power module.

[0113] In some embodiments, the power module may include only a transformer circuit to adapt to a DC power supply.

[0114] Based on the same concept, embodiments of this disclosure also provide an electronic device.

[0115] The electronic device can be a laptop computer, desktop computer, mobile phone, digital broadcasting terminal, messaging device, game console, tablet device, medical device, fitness equipment, personal digital assistant, translator, watch, bracelet, or motor vehicle with a charging power source, etc., and can be any electronic device with a charging power source. In the following description, a mobile phone is used as an example, but this disclosure is not limited to this.

[0116] In some embodiments, the electronic device may include a charging module, through which a charging circuit can charge the electronic device. For example, the charging module may be a combination of a charging port of the electronic device and charging-related circuit components.

[0117] The charging module can match the charging parameters of the electronic device with the charging parameters output by the charging circuit, so that the charging module can carry the current and voltage output by the charging circuit and realize the fast charging of the electronic device.

[0118] This disclosure reduces voltage stress on the primary circuit components of the transformer module by constructing a novel two-phase resonant circuit topology. Simultaneously, the series connection of the resonant capacitor and the use of clamping diodes enable the transformer circuit to perform over-power limiting. Furthermore, on the secondary side of the transformer module, the combination of a voltage doubler rectifier circuit and a flying capacitor achieves a higher gain voltage output. The flying capacitor also simultaneously addresses the current imbalance problem of multiphase converters, making it more suitable for high-power applications. Moreover, this transformer circuit can be easily expanded according to power requirements.

[0119] It is understood that in this disclosure, "multiple" refers to two or more, and other quantifiers are similar. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. The singular forms "a," "the," and "the" are also intended to include the plural forms unless the context clearly indicates otherwise.

[0120] It is further understood that the terms "second," "second," etc., are used to describe various types of information, but this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another, and do not indicate a specific order or degree of importance. In fact, the expressions "second," "second," etc., are completely interchangeable. For example, without departing from the scope of this disclosure, second information can also be referred to as second information, and similarly, second information can also be referred to as second information.

[0121] It is further understood that the terms “center,” “longitudinal,” “lateral,” “front,” “rear,” “up,” “down,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0122] It can be further understood that, unless otherwise specified, "connection" includes both direct connections where no other components exist between the two parties and indirect connections where other components exist between them.

[0123] It is further understood that although operations are described in a specific order in the accompanying drawings in the embodiments of this disclosure, this should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all of the shown operations to be performed to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0124] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following scope of claims.

[0125] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A transformer circuit, characterized in that, The transformer circuit includes: Input and output terminals; Multiple resonant transformer circuits, each of the multiple resonant transformer circuits includes a primary terminal, a secondary terminal, a resonant circuit, and an output circuit; The multiple resonant circuits included in the multiple resonant transformer circuits are connected in series with each other and then connected to the input terminal to input the voltage provided by the input terminal to the primary terminal; The multiple output circuits included in the multiple resonant transformer circuits are connected in parallel to each other and then connected to the output terminal. The multiple output circuits are used to boost the voltage output of the secondary terminal and to balance the current output of different secondary terminals, which are the secondary terminals in different resonant transformer circuits.

2. The transformer circuit according to claim 1, characterized in that, The output circuit includes: A voltage doubler rectifier circuit, wherein the voltage doubler rectifier circuit is connected between the secondary terminal and the output terminal; A current sharing element is connected across multiple voltage multiplier rectifier circuits in the multiple resonant transformer circuits to the output terminal.

3. The transformer circuit according to claim 2, characterized in that, The current sharing element is a capacitor; The transformer circuit includes a first state and a second state; When the transformer circuit is in the first state, a portion of the plurality of resonant transformer circuits charges the current sharing element; When the transformer circuit is in the second state, another part of the plurality of resonant transformer circuits, together with the current sharing element, outputs current to the output terminal.

4. The transformer circuit according to claim 3, characterized in that, The number of current sharing elements is N-1. Wherein, N is the number of the resonant transformer circuits.

5. The transformer circuit according to any one of claims 2-4, characterized in that, The voltage doubler rectifier circuit includes: A boosting capacitor, one end of which is connected to the secondary terminal and the other end of which is connected to the output terminal; A rectifier diode, the negative terminal of which is connected to the boost capacitor and the output terminal, and the positive terminal of which is grounded.

6. The transformer circuit according to claim 3, characterized in that, The transformer circuit also includes: A protection circuit is provided between the resonant circuit and the input terminal. When the current of the resonant circuit is greater than a threshold, the protection circuit disconnects the connection between the input terminal and the resonant circuit.

7. The transformer circuit according to claim 6, characterized in that, The resonant circuit includes a resonant capacitor, which is disposed between the input terminal and the primary terminal; The protection circuit includes a clamping diode connected in parallel with the resonant capacitor. The clamping diode is used to limit the voltage of the resonant capacitor to be less than or equal to a first threshold voltage.

8. The transformer circuit according to claim 7, characterized in that, The transformer circuit also includes: The voltage divider capacitor is connected in parallel with the input terminal and in parallel with the protection circuit; Wherein, the first threshold voltage is the voltage of the voltage divider capacitor.

9. The transformer circuit according to claim 8, characterized in that, The resonant capacitor includes a first resonant capacitor and a second resonant capacitor connected in series. One end of the first resonant capacitor is connected to the positive terminal of the input terminal, the voltage divider capacitor, and the transformer circuit, and the other end of the first resonant capacitor is connected to the second resonant capacitor and the transformer circuit. One end of the second resonant capacitor is connected to the first resonant capacitor and the transformer circuit, and the other end of the second resonant capacitor is connected to the voltage divider capacitor and the transformer circuit. The protection circuit includes a first clamping diode and a second clamping diode; The first clamping diode is connected in parallel with the first resonant capacitor, and the negative terminal of the first clamping diode is connected to the voltage dividing capacitor. The second clamping diode is connected in parallel with the second resonant capacitor, and the positive terminal of the second clamping diode is connected to the voltage dividing capacitor.

10. The transformer circuit according to claim 1, characterized in that, The resonant circuit includes: A switch group, wherein the switch group is disposed between the transformer circuit and the input terminal; There are multiple switch groups, and each switch group corresponds one-to-one with the resonant transformer circuit. The switch group controls the multiple resonant transformer circuits to alternately output current to the output terminal.

11. The transformer circuit according to claim 7, characterized in that, The primary terminal includes a magnetizing inductor and a primary coil; The resonant circuit includes a resonant inductor, one end of which is electrically connected to the magnetizing inductor and the primary coil, and the other end of which is electrically connected to the input terminal. One end of the resonant capacitor is electrically connected to the resonant inductor, and the other end of the resonant capacitor is electrically connected to the input terminal. The magnetizing inductor, the resonant inductor, and the resonant capacitor together form an inductor-inductor-capacitor resonant circuit.

12. The transformer circuit according to claim 1, characterized in that, include: An output capacitor is disposed between the output circuit and the output terminal, and the output capacitor is connected in parallel with the output terminal. The transformer circuit includes a first state and a second state; When the transformer circuit is in the first state, the output capacitor outputs current to the output terminal; When the transformer circuit is in the second state, the secondary terminal charges the output capacitor through the output circuit.

13. A charging circuit, characterized in that, include: The transformer circuit as described in any one of claims 1 to 12.

14. The charging circuit according to claim 13, characterized in that, include: A rectifier circuit, wherein the rectifier circuit is connected to the output terminal of the transformer circuit; The rectifier circuit is used to convert the direct current output by the transformer circuit into alternating current.

15. A power adapter, characterized in that, include: The transformer circuit as described in any one of claims 1 to 12, or The charging circuit as described in claims 13 to 14.

16. A power supply module, characterized in that, include: The transformer circuit as claimed in any one of claims 1 to 12, or The charging circuit as described in claims 13 to 14.

17. An electronic device, characterized in that, include: A charging module, wherein the charging parameters for charging the electronic device are matched with the charging parameters output by the charging circuit as described in claims 13 to 14.

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