WO2023246061A1 - 变压电路、电压转换电路、电子设备和电路启动方法 - Google Patents

变压电路、电压转换电路、电子设备和电路启动方法 Download PDF

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Publication number
WO2023246061A1
WO2023246061A1 PCT/CN2022/142711 CN2022142711W WO2023246061A1 WO 2023246061 A1 WO2023246061 A1 WO 2023246061A1 CN 2022142711 W CN2022142711 W CN 2022142711W WO 2023246061 A1 WO2023246061 A1 WO 2023246061A1
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Prior art keywords
switch
switching
pulse width
circuit
unit
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PCT/CN2022/142711
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English (en)
French (fr)
Inventor
郭红光
张锦
张晨松
李建国
纪策
田晨
张加亮
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Oppo广东移动通信有限公司
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Publication of WO2023246061A1 publication Critical patent/WO2023246061A1/zh

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/4815—Resonant converters
    • H02M7/4818—Resonant converters with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/32—Means for protecting converters other than automatic disconnection
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/36—Means for starting or stopping converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/01—Resonant DC/DC converters
    • H02M3/015—Resonant DC/DC converters with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuit
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Definitions

  • the present application relates to the field of circuit technology, and in particular to a transformer circuit, a voltage conversion circuit, an electronic device and a circuit starting method.
  • LLC circuit topology and LLC-DC transformer are common voltage conversion topologies in high-voltage DC-to-DC (direct current-direct current, DCDC) circuits.
  • LLC circuit topology and DCX circuit topology include half-bridge circuit (or full-bridge circuit), resonant circuit and synchronous rectification circuit, etc.
  • the resonant circuit includes: independent resonant inductor, resonant capacitor and leakage inductance of the transformer. .
  • the leakage inductance of the transformer is used as the resonant inductor in the resonant circuit, which can save an independent inductor.
  • the leakage inductance of the transformer due to the limited inductance of the leakage inductance of the transformer, it cannot suppress current mutation to a certain extent like an independent inductor. Therefore, during the startup process of LLC circuit topology and DCX circuit topology, the inrush current may be too large, causing damage to the switch tube. question.
  • the present application provides a transformer circuit, which includes a half-bridge circuit, a resonant circuit, a switch unit, and a control unit connected to the switch unit, wherein the first circuit of the resonant circuit The second end of the resonant circuit is connected to the ground between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit is grounded through the switch unit; the first switch tube and the transformer circuit are The voltage input terminal is connected, and the second switch tube is grounded;
  • the control unit is used to control the switching unit to switch from the first switching state to the second switching state to start the transformer circuit, wherein when the switching unit is in the first switching state, the The switch unit is synchronously conductive with the second switch transistor and conducts complementary conduction with the first switch transistor; when the switch unit is in the second switch state, the switch unit is normally open.
  • the present application also provides a voltage conversion circuit.
  • the voltage conversion circuit includes a transformer circuit, wherein the transformer circuit includes a half-bridge circuit, a resonant circuit, a switch unit, and is connected to the switch unit.
  • a control unit wherein the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit is grounded through the switch unit;
  • the first switch tube is connected to the voltage input end of the transformer circuit, and the second switch tube is connected to ground;
  • the control unit is used to control the switching unit to switch from the first switching state to the second switching state to start the transformer circuit, wherein when the switching unit is in the first switching state, the The switch unit is synchronously conductive with the second switch transistor and conducts complementary conduction with the first switch transistor; when the switch unit is in the second switch state, the switch unit is normally open.
  • the present application also provides an electronic device.
  • the electronic device includes a voltage conversion circuit.
  • the voltage conversion circuit includes a transformer circuit.
  • the transformer circuit includes a half-bridge circuit, a resonant circuit, and a switching unit. , and a control unit connected to the switch unit, wherein the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit The terminal is grounded through the switch unit; the first switch tube is connected to the voltage input terminal of the transformer circuit, and the second switch tube is grounded;
  • the control unit is used to control the switching unit to switch from the first switching state to the second switching state to start the transformer circuit, wherein when the switching unit is in the first switching state, the The switch unit is synchronously conductive with the second switch transistor and conducts complementary conduction with the first switch transistor; when the switch unit is in the second switch state, the switch unit is normally open.
  • the application also provides a circuit starting method, which method is applied to a transformer circuit.
  • the transformer circuit includes a half-bridge circuit, a resonant circuit, a switch unit, and a control unit connected to the switch unit. , wherein the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit is grounded through the switch unit; the third A switching tube is connected to the voltage input end of the transformer circuit, and the second switching tube is grounded.
  • the method includes:
  • the control unit controls the switch unit to switch from the first switch state to the second switch state to start the transformer circuit
  • the switch unit when the switch unit is in the first switch state, the switch unit is synchronously conductive with the second switch transistor and conducts complementary conduction with the first switch transistor; when the switch unit is in the first switch state, In the second switch state, the switch unit is normally open.
  • the above-mentioned transformer circuit, voltage conversion circuit, electronic equipment and circuit starting method start by arranging a switch unit between the half-bridge circuit and the resonant circuit, and the control unit switches from the first switch state to the second switch state by controlling the switch unit.
  • transformer circuit when the switching unit is in the first switching state, it is complementary to the first switching tube in the half-bridge circuit; when the switching tube is in the second switching state, it is normally open.
  • the control unit controls the first switching tube and the switching unit to be in the conductive state at the same time during the switching cycle and gradually increases from zero, so that the flow to resonance can be controlled during the startup process of the transformer circuit.
  • the current size of the circuit can effectively suppress the current impact in the resonant circuit and help ensure the safe start-up of the transformer circuit.
  • FIG. 1 is a schematic structural diagram of an LLC circuit topology provided in related technologies
  • Figure 2 is a schematic structural diagram of a transformer circuit provided by an embodiment of the present application.
  • Figure 3 is a schematic structural diagram of a transformer circuit provided by another embodiment of the present application.
  • Figure 4 is a schematic diagram of a driving signal provided by an embodiment of the present application.
  • FIG. 5 is a schematic structural diagram of a voltage conversion circuit provided by an embodiment of the present application.
  • connection in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have the transmission of electrical signals or data between each other.
  • LLC circuit topology and LLC-DCX circuit are common voltage conversion topologies in DCDC circuits.
  • the LLC circuit can output a stable voltage by controlling changes in frequency.
  • the main difference between the DCX circuit and the LLC circuit is that the frequency of the DCX circuit does not change during normal operation.
  • FIG 1 is a schematic structural diagram of an LLC circuit topology provided in the related art.
  • the LLC circuit topology can include a half-bridge circuit 1 (or a full-bridge circuit, as shown in Figure 1 with a half-bridge circuit as an example).
  • the resonant circuit 2, etc., wherein the resonant circuit 2 may include: an independent resonant inductor Ls, a resonant capacitor Cs and the leakage inductance Lm of the transformer.
  • the DCX circuit topology can refer to the LLC circuit topology shown in Figure 1.
  • the advantage of this topology is that it can realize zero voltage switching (Zero Voltage Switch, ZVS) of each switch tube in LLC circuit topology or DCX circuit topology, which is helpful to improve the efficiency of voltage conversion.
  • ZVS Zero Voltage Switch
  • the leakage inductance of the transformer in LLC circuit topology and DCX circuit topology is used as the resonant inductor in the resonant circuit, which can save an independent inductor.
  • the leakage inductance of the transformer due to the limited inductance of the leakage inductance of the transformer, it cannot suppress current mutation to a certain extent like an independent inductor. Therefore, during the startup process of LLC circuit topology and DCX circuit topology, the inrush current may be too large, causing damage to the switch tube. question.
  • the inrush current brought to the resonant circuit in the DCX circuit topology is not obvious, but the half-bridge circuit in the DCX circuit topology is incompatible with the voltage input.
  • the switch tube connected to the terminal is turned on, it will charge the resonant capacitor in the resonant circuit, which will cause a large inrush current.
  • a switch unit is provided between the half-bridge circuit and the transformer circuit, and the control unit switches from the first switch state to the third switch state by controlling the switch unit.
  • Second switch state to start the transformer circuit.
  • the switching unit when the switching unit is in the first switching state, it is complementary to the first switching tube in the half-bridge circuit, that is, the duration of the switching unit and the first switching tube being in the conducting state at the same time during the switching cycle is zero; when the switching tube When it is in the second switching state, it is normally open, that is, the time period during which the switching unit and the first switch tube are in the conduction state at the same time during the switching cycle is the conduction time period of the first switch tube.
  • the control unit controls the switching unit to gradually switch from the first switching state to the second switching state, so that the first switching tube and the switching unit are in the conductive state at the same time during the switching cycle. Gradually increase from zero so that the current flowing to the transformer circuit can be controlled during the startup process of the transformer circuit, thereby effectively suppressing the current impact in the transformer circuit and ensuring the safe startup of the transformer circuit.
  • FIG 2 is a schematic structural diagram of a transformer circuit provided by an embodiment of the present application.
  • the transformer circuit of the embodiment of the present application may include a half-bridge circuit 101, a resonant circuit 102, a switch unit 103, and a switch unit. 103 connected control unit 104.
  • the first end of the resonant circuit 102 is connected between the first switching tube 101A and the second switching tube 101B in the half-bridge circuit 101.
  • the first switching tube 101A is connected to the voltage input end of the transformer circuit
  • the second switching tube 101A is connected to the voltage input end of the transformer circuit.
  • the switch tube 101B is grounded; the second end of the resonant circuit 102 can be grounded through the switch unit 103 .
  • control unit 104 is also connected to the half-bridge circuit 101 (not shown in FIG. 2 ), so as to control the on-off state of the first switching transistor 101A and the second switching transistor 101B in the half-bridge circuit 101.
  • switch unit 103 involved in the embodiment of this application may be a controllable switch transistor.
  • each switching transistor or switching unit involved in the embodiment of the present application may include but is not limited to a Metal-Oxide-Semiconductor Field-Effect Transistor (MOS transistor) or use Gallium Nitride (GaN) Switch transistors made of materials, such as Metal-Semiconductor Field Effect Transistor (MESFET), Heterojunction Field Effect Transistor (HFET) or Modulated Doped Field Effect Transistor (MODFET).
  • MOS transistor Metal-Oxide-Semiconductor Field-Effect Transistor
  • GaN Gallium Nitride
  • Switch transistors made of materials, such as Metal-Semiconductor Field Effect Transistor (MESFET), Heterojunction Field Effect Transistor (HFET) or Modulated Doped Field Effect Transistor (MODFET).
  • control unit 104 involved in the embodiment of the present application may include but is not limited to a controller, where the controller may have a driving function.
  • control unit 104 involved in the embodiment of the present application may include but is not limited to a controller and a driver.
  • the controller sends a control signal to the driver, so that the driver outputs a corresponding switch to the corresponding switch tube according to the control signal. driving signal.
  • control unit 104 is used to control the switch unit 103 to switch from the first switch state to the second switch state to start the transformer circuit.
  • process of starting the transformer circuit may include but is not limited to: a process in which the output voltage of the transformer circuit increases from zero to the target voltage. The increase in the output voltage of the transformer circuit from zero to the target voltage usually requires a transformation process. Multiple switching cycles of the switch tube in the voltage circuit. The switching cycle refers to the sum of the on-time and off-time of the switch tube within the cycle.
  • the switch unit 103 when the switch unit 103 is in the first switching state, the switch unit 103 is synchronously conductive with the second switch transistor 101B in the half-bridge circuit 101, and is complementary to the first switch transistor 101A.
  • the complementary conduction between the switch unit 103 and the first switch tube means that during the switching period, when the first switch tube 101A is in the on state, the switch unit 103 is in the off state, and the first switch tube 101A is in the off state. , the switch unit 103 is in the conductive state.
  • the first switch tube 101A is connected to the voltage input terminal of the transformer circuit.
  • the front-stage circuit of the transformer circuit transmits voltage to the transformer through the voltage input terminal.
  • the circuit applies a voltage such that current flows to the resonant circuit 102 of the transformer circuit.
  • the switch unit 103 when the switch unit 103 is in the second switching state, the switch unit 103 is normally open, that is, the switch unit 103 is always in the conductive state during the switching period. At this time, the switch unit 103 and the first switch The time period during which the tube 101A is in the conductive state during the switching period is the conduction time period of the first switch tube 101A.
  • the switching unit 103 is in the first switching state, that is, the time the switching unit 103 and the first switching transistor 101A are in the conductive state at the same time in one switching cycle is zero, therefore, this There is no inrush current in the resonant circuit of the time transformer circuit.
  • the control unit 104 controls the switching unit 103 to gradually switch from the first switching state to the second switching state through multiple switching cycles, that is, the first switching tube 101A and the switching unit 103
  • the duration of the conduction state during the switching cycle is gradually increased from zero to the conduction duration of the first switching transistor 101A, so that the current flowing to the resonant circuit during the startup of the transformer circuit can be controlled, thereby effectively suppressing
  • the current impact in the resonant circuit will not cause damage to the switching tube due to too large an impact current.
  • the switching unit 103 is in the first switching state from the 1st switching cycle to the 5th switching cycle, and the switching unit 103 is in the 6th switching cycle to the 10th switching cycle.
  • cycle is in the third switching state
  • the switching unit 103 is in the fourth switching state from the 11th switching cycle to the 15th switching cycle
  • the switching unit 103 is in the second switching state from the 16th switching cycle to the 20th switching cycle, where , when the switching unit 103 is in the third switching state and the first switching transistor 101A is in the on state at the same time during the switching cycle, the duration is 1.
  • duration of the conduction state at the same time is duration 2
  • duration 1 is greater than zero and less than duration 2
  • duration 2 is smaller than the conduction duration of the first switching tube 101A in the switching cycle.
  • a switch unit is provided between the half-bridge circuit and the resonant circuit, and the control unit controls the switch unit to switch from the first switch state to the second switch state to start the transformer. voltage circuit.
  • the control unit controls the switching unit to gradually switch from the first switching state to the second switching state, so that the first switching tube and the switching unit are in the switching state at the same time during the switching period.
  • the duration of the conduction state is gradually increased from zero so that the current flowing to the resonant circuit during the startup process of the transformer circuit can be controlled, thereby effectively suppressing the current impact in the resonant circuit and ensuring the safe startup of the transformer circuit.
  • control unit 104 is also connected to the first switching tube 101A and the second switching tube 101B in the half-bridge circuit 101 (not shown in FIG. 2 ), so that the control unit 104 can output a driving signal to control the half-bridge circuit.
  • the control unit 104 can output a second driving signal to the first switching tube 101A for controlling the on-off state of the first switching tube 101A, and output to the second switching tube 101B a second driving signal for controlling the on-off state of the second switching tube 101B.
  • the third driving signal of the state is also connected to the first switching tube 101A and the second switching tube 101B in the half-bridge circuit 101 (not shown in FIG. 2 ), so that the control unit 104 can output a driving signal to control the half-bridge circuit.
  • the control unit 104 can output a second driving signal to the first switching tube 101A for controlling the on-off state of the first switching tube 101
  • any driving signal involved in the embodiment of the present application may include, but is not limited to, a pulse width modulation (Pulse width modulation, PWM) signal.
  • PWM pulse width modulation
  • the control unit 104 is used to control the first drive signal output to the switch unit 103 to increase from the first pulse width to the second pulse width.
  • the first driving signal is the first pulse width
  • the phase of the first driving signal is complementary to the phase of the second driving signal output to the first switching tube 101A, and is complementary to the phase of the third driving signal output to the second switching tube 101B.
  • the phases of the signals are the same; when the pulse width of the first driving signal of the switching unit 103 is the first pulse width, it corresponds to the above-mentioned first switching state; when the pulse width of the first driving signal of the switching unit 103 is the second pulse width, it corresponds to Corresponds to the above second switch state.
  • the first pulse width involved in the embodiment of the present application may be less than or equal to 1/2 of the pulse period of the first driving signal. It should be understood that the pulse period involved in the embodiment of the present application is equal to the above-mentioned switching period.
  • the switching unit 103 when the switching unit 103 is in the second switching state, the switching unit 103 is normally open, that is, the switching unit 103 is always in the conducting state during the switching period. Therefore, the second pulse width involved in the embodiment of the present application may be equal to pulse period.
  • control unit 104 can control the first driving signal output to the switching unit 103 to gradually increase from the first pulse width to the second pulse width through multiple switching cycles during the startup process of the transformer circuit.
  • the duration during which the first switching tube 101A and the switching unit 103 are in the conductive state at the same time during the switching cycle gradually increases from zero to the conduction duration of the first switching tube 101A, so that the process of starting the transformer circuit can be controlled.
  • the size of the current flowing to the resonant circuit can effectively suppress the current impact in the resonant circuit.
  • the pulse width of the first driving signal of the switching unit 103 in the 1st switching cycle to the 5th switching cycle is the first pulse width
  • the switching unit 103 switches in the 6th switching cycle.
  • the pulse width of the first driving signal of the switching period to the 10th switching period is the third pulse width
  • the pulse width of the first driving signal of the switching unit 103 during the 11th switching period to the 15th switching period is the fourth pulse.
  • the pulse width of the first driving signal of the switching unit 103 in the 16th switching cycle to the 20th switching cycle is the second pulse width
  • the pulse width of the second driving signal of the first switching tube 101A in the above 20 switching cycles Can be equal to the first pulse width (complementary to the phase of the first drive signal).
  • the overlapping pulse width between the third pulse width and the pulse width of the second driving signal is pulse width 1
  • the overlapping pulse width between the fourth pulse width and the pulse width of the second driving signal is pulse width 2
  • the pulse width is 1 is greater than zero and less than pulse width 2 is less than the pulse width of the second driving signal.
  • control unit 104 can control the first driving signal to randomly increase the first preset pulse width from the first pulse width every at least one pulse period until it increases to the second pulse width, where the first The preset pulse width can be a random pulse width.
  • control unit 104 can control the first driving signal to increase from the first pulse width to the second preset pulse width every first preset pulse period until it increases to the second pulse width, where the The second preset pulse width may be a fixed value, or the second preset pulse width may increase during the startup process of the transformer circuit.
  • the second preset pulse width may increase the third preset pulse width every second preset pulse period, and the third preset pulse width may be a fixed value.
  • the pulse width of the first drive signal used to control the conduction of the switch unit and the pulse width of the drive signal used to control the conduction of each switch tube in the half-bridge circuit are Width has a certain width. It can be seen that the switch tube involved in the embodiment of the present application will be turned on for a relatively long time during the pulse cycle. Therefore, there is no need to consider the minimum conduction time requirement of the controller or driver with a driving function. Therefore, Can be adapted to various controllers or drives with drive functions.
  • the drain of the first switch 101A is connected to the voltage input terminal of the transformer circuit
  • the source of the first switch 101A and the drain of the second switch 101B are connected to the resonant inductor L
  • the drain of the switch 103 The pole is connected to the resonant capacitor C
  • the source stage of the second switch tube 101B and the source stage of the switch tube 103 are grounded. It should be understood that the positions of the resonant capacitor C and the resonant inductor L in the resonant circuit 102 in FIG. 3 can be interchanged.
  • the gate electrode of the switch tube 103 can be connected to the above-mentioned control unit 104, so as to receive the first driving signal sent by the above-mentioned control unit 104; the gate electrode of the first switch tube 101A can be connected to the above-mentioned control unit 104, In order to receive the second driving signal sent by the above-mentioned control unit 104; the gate of the second switch tube 101B can be connected with the above-mentioned control unit 104 in order to receive the third driving signal sent by the above-mentioned control unit 104.
  • FIG. 4 is a schematic diagram of a driving signal provided by an embodiment of the present application.
  • the control unit 104 can control the phase and phase of the first driving signal in the first pulse period (or when the transformer circuit is just started).
  • the phase of the second driving signal is complementary and is the same as the phase of the third driving signal, wherein the pulse widths of the first driving signal, the second driving signal and the third driving signal may all be the first pulse width, and the first pulse width may be It is equal to 1/2 of the pulse period T (not considering the switching dead time), that is, the duty ratios of the first drive signal, the second drive signal and the third drive signal are all 50%.
  • the control unit can control the first driving signal to gradually increase from the fourth pulse width to the second pulse width in the j+1th pulse period to the kth pulse period, wherein the duty cycle of the first driving signal can be 100 %, k is an integer greater than j.
  • the control unit 104 controls the first drive signal output to the switch unit 103 to gradually increase from the first pulse width to the second pulse width, so that the transformer circuit can be started.
  • the duration during which the first switch tube 101A and the switch unit 103 are in the conductive state at the same time during the pulse period gradually increases from zero, so that the current flowing to the resonant circuit during the startup process of the transformer circuit can be controlled, thereby It can effectively suppress the current impact in the resonant circuit and help ensure the safe starting of the transformer circuit.
  • a voltage conversion circuit may include the above-mentioned transformer circuit, wherein the transformer circuit includes a half-bridge circuit, a resonant circuit, a switch unit, and a control unit connected to the switch unit, wherein , the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, the second end of the resonant circuit is grounded through the switch unit; the first switch tube is connected to the voltage input end of the transformer circuit , the second switch tube is grounded;
  • control unit is also connected to the first switch tube and the second switch tube respectively;
  • the control unit is also used to control the first drive signal output to the switch unit to increase from the first pulse width to the second pulse width;
  • the phase of the first driving signal when the first driving signal is the first pulse width, is complementary to the phase of the second driving signal output to the first switching tube, and is complementary to the phase of the third driving signal output to the second switching tube.
  • the phases are the same; when the first driving signal is the second pulse width, the switch unit is in a normally open state.
  • control unit is configured to: control the first driving signal to increase from the first pulse width to a preset pulse width every preset pulse period until it increases to the second pulse width.
  • the preset pulse width is a fixed value, or the preset pulse width increases during the startup process of the transformer circuit.
  • the first pulse width is less than or equal to 1/2 of the pulse period of the first driving signal, and the second pulse width is equal to the pulse period.
  • the voltage conversion circuit provided in the embodiments of this application may include the voltage transformation circuit provided in the above embodiments of this application. Its implementation principles and technical effects are similar and will not be described again here.
  • the embodiment of the present application introduces the implementation method of the front and rear stage circuits of the transformer circuit in the voltage conversion circuit.
  • Figure 5 is a schematic structural diagram of a voltage conversion circuit provided by an embodiment of the present application.
  • the front-end circuit of the transformer circuit may also include a rectifier bridge circuit and a power factor correction (Power Factor Correction, PFC) circuit
  • the downstream circuit of the transformer circuit may also include a synchronous rectifier circuit and a voltage stabilizing circuit.
  • PFC Power Factor Correction
  • the voltage conversion circuit in the embodiment of the present application may also include other circuit units, which is not limited in the embodiment of the present application.
  • an electronic device may include the voltage conversion circuit provided in the above embodiment of the present application.
  • the voltage conversion circuit may include a transformer circuit, wherein the transformer circuit may include a half-bridge circuit and a resonant circuit. , a switch unit, and a control unit connected to the switch unit, wherein the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit is grounded through the switch unit ;
  • the first switch tube is connected to the voltage input end of the transformer circuit, and the second switch tube is connected to ground;
  • the control unit is used to control the switching unit to switch from the first switching state to the second switching state to start the transformer circuit, wherein when the switching unit is in the first switching state, the switching unit and the second switching tube are synchronously conducted, and It is complementary to the first switching tube and conducts; when the switching unit is in the second switching state, the switching unit is normally open.
  • control unit is also connected to the first switch tube and the second switch tube respectively;
  • control unit for outputting a driving signal to control the first switching tube and the second switching tube
  • the control unit is also used to control the first drive signal output to the switch unit to increase from the first pulse width to the second pulse width;
  • the phase of the first driving signal when the first driving signal is the first pulse width, is complementary to the phase of the second driving signal output to the first switching tube, and is complementary to the phase of the third driving signal output to the second switching tube.
  • the phases are the same; when the first driving signal is the second pulse width, the switch unit is in a normally open state.
  • control unit is configured to: control the first driving signal to increase from the first pulse width to a preset pulse width every preset pulse period until it increases to the second pulse width.
  • the preset pulse width is a fixed value, or the preset pulse width increases during the startup process of the transformer circuit.
  • the first pulse width is less than or equal to 1/2 of the pulse period of the first driving signal, and the second pulse width is equal to the pulse period.
  • the electronic equipment provided in the embodiments of this application may include the transformer circuit provided in the above embodiments of this application. Its implementation principles and technical effects are similar and will not be described again here.
  • the electronic devices involved in the embodiments of this application may include, but are not limited to: power adapters, mobile power supplies, mobile phones, laptops, tablets, smart watches, smart bracelets, sweeping machines, wireless headsets, electric toothbrushes or desktops. computer.
  • a circuit starting method for use in the transformer circuit provided in the above embodiment of the present application.
  • the transformer circuit includes a half-bridge circuit, a resonant circuit, a switch unit, and a control unit connected to the switch unit. unit, wherein the first end of the resonant circuit is connected between the first switch tube and the second switch tube in the half-bridge circuit, and the second end of the resonant circuit is grounded through the switch unit; the voltage between the first switch tube and the transformer circuit The input terminal is connected and the second switch tube is grounded.
  • the method includes:
  • the control unit controls the switch unit to switch from the first switch state to the second switch state to start the transformer circuit
  • the switch unit when the switch unit is in the first switch state, the switch unit is synchronously conductive with the second switch transistor and conducts complementary conduction with the first switch transistor; when the switch unit is in the second switch state, the switch unit is normally open.
  • control unit is also connected to the first switching tube and the second switching tube respectively, and the method further includes:
  • the control unit outputs a driving signal to control the first switching tube and the second switching tube;
  • control unit controls the switch unit to switch from the first switch state to the second switch state, including:
  • the control unit controls the first drive signal output to the switch unit to increase incrementally from a first pulse width to a second pulse width;
  • the phase of the first driving signal when the first driving signal is the first pulse width, is complementary to the phase of the second driving signal output to the first switching tube, and is complementary to the phase of the third driving signal output to the second switching tube.
  • the phases are the same; when the first driving signal is the second pulse width, the switch unit is in a normally open state.
  • the control unit controls the first driving signal to increase from the first pulse width to the preset pulse width every preset pulse period until it increases to the second pulse width.
  • the preset pulse width is a fixed value, or the preset pulse width increases during the startup process of the transformer circuit.
  • the first pulse width is less than or equal to 1/2 of the pulse period of the first driving signal, and the second pulse width is equal to the pulse period.
  • circuit starting method provided by the embodiments of this application can be applied to the transformer circuit provided by the above embodiments of this application. Its implementation principles and technical effects are similar and will not be described again here.

Abstract

本申请涉及一种变压电路、电压转换电路、电子设备和电路启动方法，通过在半桥电路与谐振电路之间设置开关单元，控制单元通过控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路。其中，当开关单元处于第一开关状态时与半桥电路中的第一开关管互补导通；当开关单元处于第二开关状态时为常开。可见，控制单元在变压电路启动过程中，通过控制开关单元由第一开关状态逐步切换至第二开关状态的方式，使得第一开关管与开关单元在开关周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。

Description

变压电路、电压转换电路、电子设备和电路启动方法
本申请引用于2022年6月20日递交的名称为“变压电路、电压转换电路、电子设备和电路启动方法”，申请号为2022106972514的中国专利申请，其通过引用被全部并入本申请。
技术领域
本申请涉及电路技术领域，特别是涉及一种变压电路、电压转换电路、电子设备和电路启动方法。
背景技术
LLC电路拓扑和LLC-直流变压器(direct current transformer，DCX)电路拓扑(以下简称为DCX电路拓扑)是常见的高压直流转直流(direct current-direct current，DCDC)电路中的电压转换拓扑结构。
通常情况下，LLC电路拓扑和DCX电路拓扑中包括半桥电路(或全桥电路)、谐振电路和同步整流电路等，其中，谐振电路中包括：独立的谐振电感、谐振电容和变压器的漏感。
随着电路空间结构限制或者成本限制等，LLC电路拓扑和DCX电路拓扑中通过变压器的漏感作为谐振电路中的谐振电感，可以节省一个独立的电感。但是由于变压器的漏感的感量有限，无法像独立的电感具有一定的抑制电流突变的能力，因此，在LLC电路拓扑和DCX电路拓扑启动过程中，会存在冲击电流太大导致损坏开关管的问题。
发明内容
基于此，有必要针对上述技术问题，提供一种变压电路、电压转换电路、电子设备和电路启动方法。
第一方面，本申请提供了一种变压电路，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述 半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地；
所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
第二方面，本申请还提供了一种电压转换电路，所述电压转换电路包括变压电路，其中，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地；
所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
第三方面，本申请还提供了一种电子设备，所述电子设备包括电压转换电路，所述电压转换电路包括变压电路，其中，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地；
所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
第四方面，本申请还提供了一种电路启动方法，所述方法应用于变压电路，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振 电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地，所述方法包括：
所述控制单元控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路；
其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
上述变压电路、电压转换电路、电子设备和电路启动方法，通过在半桥电路与谐振电路之间设置开关单元，控制单元通过控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路。其中，当开关单元处于第一开关状态时与半桥电路中的第一开关管互补导通；当开关管处于第二开关状态时为常开。可见，控制单元在变压电路启动过程中，通过控制第一开关管与开关单元在开关周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。
附图说明
图1为相关技术中提供的LLC电路拓扑的结构示意图；
图2为本申请一个实施例提供的变压电路的结构示意图；
图3为本申请另一个实施例提供的变压电路的结构示意图；
图4为本申请实施例提供的驱动信号的示意图；
图5为本申请实施例提供的电压转换电路的结构示意图。
具体实施方式
为了便于理解本申请，下面将参照相关附图对本申请进行更全面的描述。附图中给出了本申请的实施例。但是，本申请可以以许多不同的形式来实现，并不限于本文所描述的实施例。相反地，提供这些实施例的目的是使本申请的公开内容更加透彻全面。
可以理解，本申请所使用的术语“第一”、“第二”等可在本文中用于描述各种元件， 但这些元件不受这些术语限制。这些术语仅用于将第一个元件与另一个元件区分。
可以理解，以下实施例中的“连接”，如果被连接的电路、模块、单元等相互之间具有电信号或数据的传递，则应理解为“电连接”、“通信连接”等。
在此使用时，单数形式的“一”、“一个”和“所述/该”也可以包括复数形式，除非上下文清楚指出另外的方式。还应当理解的是，术语“包括/包含”或“具有”等指定所陈述的特征、整体、步骤、操作、组件、部分或它们的组合的存在，但是不排除存在或添加一个或更多个其他特征、整体、步骤、操作、组件、部分或它们的组合的可能性。
LLC电路拓扑和LLC-DCX电路(以下简称为DCX电路拓扑)是常见的DCDC电路中的电压转换拓扑结构。其中，LLC电路可以通过控制频率的变化以输出稳定的电压，DCX电路与LLC电路的主要区别在于DCX电路在正常工作时的频率不变。
图1为相关技术中提供的LLC电路拓扑的结构示意图，如图1所示，LLC电路拓扑中可以包括半桥电路1(或全桥电路，图1中以半桥电路为例示出的)和谐振电路2等，其中，谐振电路2中可以包括：独立的谐振电感Ls、谐振电容Cs和变压器的漏感Lm。需要说明的是，DCX电路拓扑可以参考如图1所示的LLC电路拓扑结构。这种拓扑结构的优势在于可以实现LLC电路拓扑或者DCX电路拓扑中各开关管的零电压开关(Zero Voltage Switch，ZVS)，从而有利于提高电压转换的效率。
随着对电路空间结构限制或者成本限制等，LLC电路拓扑和DCX电路拓扑中通过变压器的漏感作为谐振电路中的谐振电感，可以节省一个独立的电感。但是由于变压器的漏感的感量有限，无法像独立的电感具有一定的抑制电流突变的能力，因此，在LLC电路拓扑和DCX电路拓扑启动过程中，会存在冲击电流太大导致损坏开关管的问题。
例如，DCX电路拓扑启动过程中，由于DCX电路拓扑的容性负载相对较小，给DCX电路拓扑中的谐振电路带来的冲击电流不明显，但DCX电路拓扑中的半桥电路中与电压输入端连接的开关管导通时会给谐振电路中的谐振电容充电，会导致很大的冲击电流。
本申请实施例提供的变压电路、电压转换电路、电子设备和电路启动方法，通过在半桥电路与变压电路之间设置开关单元，控制单元通过控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路。其中，当开关单元处于第一开关状态时与半桥电路中的第一开关管互补导通，即开关单元与第一开关管在开关周期内同时处于导通状态的时长为 零；当开关管处于第二开关状态时为常开，即开关单元与第一开关管在开关周期内同时处于导通状态的时长为第一开关管的导通时长。可见，控制单元在变压电路启动过程中，通过控制开关单元由第一开关状态逐步切换至第二开关状态的方式，使得第一开关管与开关单元在开关周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向变压电路的电流大小，从而可以有效地抑制变压电路内的电流冲击，有利于保证变压电路的安全启动。
图2为本申请一个实施例提供的变压电路的结构示意图，如图2所示，本申请实施例的变压电路可以包括半桥电路101、谐振电路102、开关单元103，以及与开关单元103连接的控制单元104。
示例性地，谐振电路102的第一端连接到半桥电路101中的第一开关管101A和第二开关管101B之间，第一开关管101A与变压电路的电压输入端连接，第二开关管101B接地；谐振电路102的第二端可以通过开关单元103接地。
应理解，控制单元104还与半桥电路101连接(图2中未示出)，以便于控制半桥电路101中的第一开关管101A和第二开关管101B的通断状态。。可选地，本申请实施例中涉及的开关单元103可以为可控开关管。
可选地，本申请实施例中涉及的各开关管或者开关单元可以包括但不限于金氧半场效晶体管(Metal-Oxide-Semiconductor Field-Effect Transistor，MOS管)或者利用氮化镓(GaN)材料制备出的开关管，例如，金属-半导体场效应晶体管(Metal-Semiconductor Field Effect Transistor，MESFET)、异质结场效应晶体管(HFET)或者调制掺杂场效应晶体管(MODFET)。
示例性地，本申请实施例中涉及的控制单元104可以包括但不限于控制器，其中，控制器可以具有驱动功能。又一示例性地，本申请实施例中涉及的控制单元104可以包括但不限于控制器和驱动器，其中，控制器向驱动器发送控制信号，以使驱动器根据控制信号向对应的开关管输出对应的驱动信号。
本申请实施例中，控制单元104用于控制开关单元103由第一开关状态切换至第二开关状态，以启动变压电路。需要说明的是，变压电路启动的过程可以包括但不限于：变压 电路的输出电压从零增加到目标电压的过程，其中，变压电路的输出电压从零增加到目标电压通常需要经过变压电路中开关管的多个开关周期，开关周期指的是开关管在周期内的导通时长和断开时长的总和。
一种可能的实现方式中，当开关单元103处于第一开关状态时，开关单元103与半桥电路101中的第二开关管101B同步导通，且与第一开关管101A互补导通。其中，开关单元103与第一开关管互补导通是指：在开关周期内，第一开关管101A处于导通状态时，开关单元103处于断开状态，以及第一开关管101A处于断开状态时，开关单元103处于导通状态。
需要说明的是，第一开关管101A与变压电路的电压输入端连接，第一开关管101A与开关单元103同时处于导通状态时，变压电路的前级电路通过电压输入端向变压电路施加电压，使得电流流向变压电路的谐振电路102。
另一种可能的实现方式中，当开关单元103处于第二开关状态时，开关单元103为常开，即开关单元103在开关周期内一直处于导通状态，此时开关单元103与第一开关管101A在开关周期内同时处于导通状态的时长为第一开关管101A的导通时长。
应理解，由于在变压电路刚启动的时候，开关单元103处于第一开关状态，即开关单元103与第一开关管101A在一个开关周期内同时处于导通状态的时长为零，因此，此时变压电路的谐振电路中没有冲击电流。
本申请实施例中，控制单元104在变压电路启动的过程中，控制开关单元103由第一开关状态通过多个开关周期逐步切换至第二开关状态，即第一开关管101A与开关单元103在开关周期内同时处于导通状态的时长由零逐步增加到第一开关管101A的导通时长，以便于可以控制在变压电路启动的过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，不会存在冲击电流太大导致损坏开关管的问题。
需要说明的是，第一开关管101A与开关单元103在开关周期内同时处于导通状态的时长越大，则流向谐振电路的电流会越大，或者说，第一开关管101A与开关单元103在开关周期内同时处于导通状态的时长越小，则流向谐振电路的电流会越小。
例如，假设变压电路启动的过程包括20个开关周期，开关单元103在第1个开关周期-第5个开关周期处于第一开关状态，开关单元103在第6个开关周期-第10个开关周期 处于第三开关状态，开关单元103在第11个开关周期-第15个开关周期处于第四开关状态，开关单元103在第16个开关周期-第20个开关周期处于第二开关状态，其中，开关单元103处于第三开关状态时与第一开关管101A在开关周期内同时处于导通状态的时长为时长1，开关单元103处于第四开关状态时与第一开关管101A在开关周期内同时处于导通状态的时长为时长2，时长1大于零，且小于时长2，时长2小于第一开关管101A在开关周期内的导通时长。
综上所述，本申请实施例提供的变压电路，通过在半桥电路与谐振电路之间设置开关单元，控制单元通过控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路。其中，当开关单元处于第一开关状态时与半桥电路中的第一开关管互补导通；当开关管处于第二开关状态时为常开。可见，本申请实施例的变压电路在启动过程中，控制单元通过控制开关单元由第一开关状态逐步切换至第二开关状态的方式，使得第一开关管与开关单元在开关周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。
在上述实施例的基础上，本申请实施例中对控制单元104控制开关单元103由第一开关状态切换至第二开关状态的可实现方式进行介绍。
应理解，控制单元104还分别与半桥电路101中的第一开关管101A和第二开关管101B连接(图2中未示出)，以便于控制单元104可以输出驱动信号以控制半桥电路101中的第一开关管101A和第二开关管101B。示例性地，控制单元104可以向第一开关管101A输出用于控制第一开关管101A通断状态的第二驱动信号，以及向第二开关管101B输出用于控制第二开关管101B通断状态的第三驱动信号。
示例性地，本申请实施例中涉及的任意驱动信号可以包括但不限于脉冲宽度调制(Pulse width modulation，PWM)信号。
本申请实施例中，控制单元104用于控制向开关单元103输出的第一驱动信号由第一脉宽增至第二脉宽。其中，在第一驱动信号为第一脉宽时，第一驱动信号的相位与向第一开关管101A输出的第二驱动信号的相位互补，且与向第二开关管101B输出的第三驱动信 号的相位相同；当开关单元103的第一驱动信号的脉宽为第一脉宽时与上述第一开关状态对应；当开关单元103的第一驱动信号的脉宽为第二脉宽时与上述第二开关状态对应。
示例性地，本申请实施例中涉及的第一脉宽可以小于等于第一驱动信号的脉冲周期的1/2。应理解，本申请实施例中涉及的脉冲周期等于上述开关周期。
应理解，当开关单元103处于第二开关状态时，开关单元103为常开，即开关单元103在开关周期内一直处于导通状态，因此，本申请实施例中涉及的第二脉宽可以等于脉冲周期。
示例性地，本申请实施例中，控制单元104可以在变压电路启动的过程中，控制向开关单元103输出的第一驱动信号由第一脉宽通过多个开关周期逐步递增至第二脉宽，即第一开关管101A与开关单元103在开关周期内同时处于导通状态的时长由零逐步增加到第一开关管101A的导通时长，以便于可以控制在变压电路启动的过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击。
例如，假设变压电路启动的过程包括20个开关周期，开关单元103在第1个开关周期-第5个开关周期的第一驱动信号的脉宽为第一脉宽，开关单元103在第6个开关周期-第10个开关周期的第一驱动信号的脉宽为第三脉宽，开关单元103在第11个开关周期-第15个开关周期的第一驱动信号的脉宽为第四脉宽，开关单元103在第16个开关周期-第20个开关周期的第一驱动信号的脉宽为第二脉宽，第一开关管101A在上述20个开关周期的第二驱动信号的脉宽可以等于第一脉宽(与第一驱动信号的相位互补)。其中，第三脉宽与第二驱动信号的脉宽之间的重合脉宽为脉宽1，第四脉宽与第二驱动信号的脉宽之间的重合脉宽为脉宽2，脉宽1大于零，且小于脉宽2，脉宽2小于第二驱动信号的脉宽。
一种可能的实现方式中，控制单元104可以控制第一驱动信号由第一脉宽每隔至少一个脉冲周期随机地增加第一预设脉宽，直至增至第二脉宽，其中，第一预设脉宽可以为随机地任意脉宽。
另一种可能的实现方式中，控制单元104可以控制第一驱动信号由第一脉宽每隔第一预设脉冲周期增加第二预设脉宽，直至增至第二脉宽，其中，第二预设脉宽可以为固定值，或者第二预设脉宽可以在变压电路启动的过程中递增。例如，第二预设脉宽可以每隔第二 预设脉冲周期增加第三预设脉宽，第三预设脉宽可以为固定值。
本实现方式中，通过控制第一脉宽递增至第二脉宽的方式，可以更加精准地控制在变压电路启动的过程中流向谐振电路的电流大小，从而可以进一步地有效抑制谐振电路内的电流冲击。
当然，控制单元104在变压电路启动的过程中，还可以控制第一驱动信号由第一脉宽通过其它方式递增至第二脉宽，本申请实施例中对此不作限制。
综上所述，本申请实施例提供的变压电路，通过控制单元104控制向开关单元103输出的第一驱动信号由第一脉宽逐步递增至第二脉宽，其中，在第一驱动信号为第一脉宽时，第一驱动信号的相位与向第一开关管输出的第二驱动信号的相位互补，以及在第一驱动信号为第二脉宽时，开关单元为常开状态。本申请实施例可以使得在变压电路启动过程中，第一开关管101A与开关单元103在脉冲周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。
另外，本申请实施例中在变压电路启动的过程中，用于控制开关单元导通的第一驱动信号的脉宽和用于控制半桥电路中的各开关管导通的驱动信号的脉宽均具有一定宽度，可见，本申请实施例中涉及的开关管在脉冲周期都会导通一段比较长的时间，因此，不需要考虑具有驱动功能的控制器或者驱动器的最小导通时间要求，从而可以适应各种具有驱动功能的控制器或者驱动器。
为了便于理解，本申请下述实施例中以各开关管和开关单元均为NMOS晶体管为例，对本申请实施例的变压电路进行介绍。
在一个实施例中，图3为本申请另一个实施例提供的变压电路的结构示意图，在上述实施例的基础上，如图3所示，本申请实施例的变压电路可以包括半桥电路101、谐振电路102、开关单元103以及控制单元104。示例性地，半桥电路101可以包括：第一开关管101A和第二开关管101B，开关单元103可以包括开关管；谐振电路102可以包括：谐振电容C和谐振电感L，谐振电感L可以用于代表变压器的漏感。
当然，谐振电感L还可以代表变压器的漏感和独立电感，其中，该独立电感的电感量 可以较小。需要说明的是，对于仍然使用独立电感但独立电感的电感量较小的变压电路，通过本申请实施例提供的方式也可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。
示例性地，第一开关管101A的漏极与变压电路的电压输入端连接，第一开关管101A的源级和第二开关管101B的漏极与谐振电感L连接，开关管103的漏极与谐振电容C连接，第二开关管101B的源级和开关管103的源级接地。应理解，图3中的谐振电路102中的谐振电容C和谐振电感L的位置可以互换。
需要说明的是，开关管103的栅极可以与上述控制单元104连接，以便于接收上述控制单元104所发送的第一驱动信号；第一开关管101A的栅极可以与上述控制单元104连接，以便于接收上述控制单元104所发送的第二驱动信号；第二开关管101B的栅极可以与上述控制单元104连接，以便于接收上述控制单元104所发送的第三驱动信号。
图4为本申请实施例提供的驱动信号的示意图，如图4所示，控制单元104在第一个脉冲周期(或者说变压电路刚启动的时候)，可以控制第一驱动信号的相位与第二驱动信号的相位互补，且与第三驱动信号的相位相同，其中，第一驱动信号、第二驱动信号和第三驱动信号的脉宽可以均为第一脉宽，第一脉宽可以等于脉冲周期T的1/2(不考虑开关死区时间)，即第一驱动信号、第二驱动信号和第三驱动信号的占空比均为50％。
进一步地，控制单元在变压电路刚启动过程中，可以控制第一驱动信号由第一脉宽逐步递增至第二脉宽。例如，1)控制单元在第2个脉冲周期至第i个脉冲周期可以控制第一驱动信号由第一脉宽逐步增加至第三脉宽，其中，第一驱动信号的占空比可以为60％，i为大于1的整数。2)控制单元在第i+1个脉冲周期至第j个脉冲周期可以控制第一驱动信号由第三脉宽逐步增加至第四脉宽，其中，第一驱动信号的占空比可以为75％，j为大于i的整数。3)控制单元在第j+1个脉冲周期至第k个脉冲周期可以控制第一驱动信号由第四脉宽逐步增加至第二脉宽，其中，第一驱动信号的占空比可以为100％，k为大于j的整数。
应理解，对于上述任意开关管，当该开关管对应的驱动信号为高电平时，该开关管处于导通状态；当该开关管对应的驱动信号为低电平时，该开关管处于断开状态。
可见，本申请实施例中，控制单元104在变压电路启动的过程中，通过控制向开关单元103输出的第一驱动信号由第一脉宽逐步递增至第二脉宽，从而可以使得在变压电路启 动过程中，第一开关管101A与开关单元103在脉冲周期内同时处于导通状态的时长由零逐步增加，以便于可以控制在变压电路启动过程中流向谐振电路的电流大小，从而可以有效地抑制谐振电路内的电流冲击，有利于保证变压电路的安全启动。
在一个实施例中，提供了一种电压转换电路，电压转换电路可以包括上述变压电路，其中，变压电路包括半桥电路、谐振电路、开关单元，以及与开关单元连接的控制单元，其中，谐振电路的第一端连接到半桥电路中的第一开关管和第二开关管之间，谐振电路的第二端通过开关单元接地；第一开关管与变压电路的电压输入端连接，第二开关管接地；
控制单元，用于控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路，其中，当开关单元处于第一开关状态时，开关单元与第二开关管同步导通，且与第一开关管互补导通；当开关单元处于第二开关状态时，开关单元为常开。
在一个实施例中，控制单元还分别与第一开关管和第二开关管连接；
控制单元，用于输出驱动信号以控制第一开关管和第二开关管；
控制单元，还用于控制向开关单元输出的第一驱动信号由第一脉宽增至第二脉宽；
其中，在第一驱动信号为第一脉宽时，第一驱动信号的相位与向第一开关管输出的第二驱动信号的相位互补，且与向第二开关管输出的第三驱动信号的相位相同；在第一驱动信号为第二脉宽时，开关单元为常开状态。
在一个实施例中，控制单元用于：控制第一驱动信号由第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至第二脉宽。
在一个实施例中，预设脉宽为固定值，或者，预设脉宽在变压电路启动的过程中递增。
在一个实施例中，第一脉宽小于等于第一驱动信号的脉冲周期的1/2，第二脉宽等于脉冲周期。
本申请实施例中提供的电压转换电路可以包括本申请上述实施例中提供的变压电路，其实现原理和技术效果类似，此处不再赘述。
在一个实施例中，本申请实施例中对电压转换电路中变压电路的前后级电路的可实现方式进行介绍。图5为本申请实施例提供的电压转换电路的结构示意图，可选地，如图5所示，变压电路的前级电路还可以包括整流桥电路和功率因数校正(Power Factor  Correction，PFC)电路，变压电路的后级电路还可以包括同步整流电路和稳压电路。
当然，本申请实施例的电压转换电路还可以包括其它电路单元，本申请实施例中对此并不作限定。
在一个实施例中，提供了一种电子设备，电子设备可以包括本申请上述实施例中提供的电压转换电路，电压转换电路可以包括变压电路，其中，变压电路包括半桥电路、谐振电路、开关单元，以及与开关单元连接的控制单元，其中，谐振电路的第一端连接到半桥电路中的第一开关管和第二开关管之间，谐振电路的第二端通过开关单元接地；第一开关管与变压电路的电压输入端连接，第二开关管接地；
控制单元，用于控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路，其中，当开关单元处于第一开关状态时，开关单元与第二开关管同步导通，且与第一开关管互补导通；当开关单元处于第二开关状态时，开关单元为常开。
在一个实施例中，控制单元还分别与第一开关管和第二开关管连接；
控制单元，用于输出驱动信号以控制第一开关管和第二开关管；
控制单元，还用于控制向开关单元输出的第一驱动信号由第一脉宽增至第二脉宽；
其中，在第一驱动信号为第一脉宽时，第一驱动信号的相位与向第一开关管输出的第二驱动信号的相位互补，且与向第二开关管输出的第三驱动信号的相位相同；在第一驱动信号为第二脉宽时，开关单元为常开状态。
在一个实施例中，控制单元用于：控制第一驱动信号由第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至第二脉宽。
在一个实施例中，预设脉宽为固定值，或者，预设脉宽在变压电路启动的过程中递增。
在一个实施例中，第一脉宽小于等于第一驱动信号的脉冲周期的1/2，第二脉宽等于脉冲周期。
本申请实施例中提供的电子设备可以包括本申请上述实施例中提供的变压电路，其实现原理和技术效果类似，此处不再赘述。
示例性地，本申请实施例中涉及的电子设备可以包括但不限于：电源适配器、移动电源、手机、笔记本电脑、平板电脑、智能手表、智能手环、扫地机器、无线耳机、电动牙 刷或台式电脑。
在一个实施例中，提供了一种电路启动方法，用于本申请上述实施例中提供的变压电路中，变压电路包括半桥电路、谐振电路、开关单元，以及与开关单元连接的控制单元，其中，谐振电路的第一端连接到半桥电路中的第一开关管和第二开关管之间，谐振电路的第二端通过开关单元接地；第一开关管与变压电路的电压输入端连接，第二开关管接地，方法包括：
控制单元控制开关单元由第一开关状态切换至第二开关状态，以启动变压电路；
其中，当开关单元处于第一开关状态时，开关单元与第二开关管同步导通，且与第一开关管互补导通；当开关单元处于第二开关状态时，开关单元为常开。
在一个实施例中，控制单元还分别与第一开关管和第二开关管连接，方法还包括：
控制单元输出驱动信号以控制第一开关管和第二开关管；
对应地，控制单元控制开关单元由第一开关状态切换至第二开关状态，包括：
控制单元控制向开关单元输出的第一驱动信号由第一脉宽递增至第二脉宽；
其中，在第一驱动信号为第一脉宽时，第一驱动信号的相位与向第一开关管输出的第二驱动信号的相位互补，且与向第二开关管输出的第三驱动信号的相位相同；在第一驱动信号为第二脉宽时，开关单元为常开状态。
在一个实施例中，控制单元控制向开关单元输出的第一驱动信号由第一脉宽递增至第二脉宽，包括：
控制单元控制第一驱动信号由第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至第二脉宽。
在一个实施例中，预设脉宽为固定值，或者，预设脉宽在变压电路启动的过程中递增。
在一个实施例中，第一脉宽小于等于第一驱动信号的脉冲周期的1/2，第二脉宽等于脉冲周期。
本申请实施例提供的电路启动方法可以应用于本申请上述实施例提供的变压电路中，其实现原理和技术效果类似，此处不再赘述。
以上实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的 各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上所述实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对本申请专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。因此，本申请的保护范围应以所附权利要求为准。

Claims (20)

  1. 一种变压电路，其特征在于，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地；
    所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
  2. 根据权利要求1所述的变压电路，其特征在于，所述控制单元还分别与所述第一开关管和所述第二开关管连接；
    所述控制单元，用于输出驱动信号以控制所述第一开关管和所述第二开关管；
    所述控制单元，还用于控制向所述开关单元输出的第一驱动信号由第一脉宽增至第二脉宽；
    其中，在所述第一驱动信号为所述第一脉宽时，所述第一驱动信号的相位与向所述第一开关管输出的第二驱动信号的相位互补，且与向所述第二开关管输出的第三驱动信号的相位相同；在所述第一驱动信号为所述第二脉宽时，所述开关单元为常开状态。
  3. 根据权利要求2所述的变压电路，其特征在于，所述控制单元用于：控制所述第一驱动信号由所述第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至所述第二脉宽。
  4. 根据权利要求3所述的变压电路，其特征在于，所述预设脉宽为固定值，或者，所述预设脉宽在所述变压电路启动的过程中递增。
  5. 根据权利要求2至4任一所述的变压电路，其特征在于，所述第一脉宽小于等于所述第一驱动信号的脉冲周期的1/2，所述第二脉宽等于所述脉冲周期。
  6. 一种电压转换电路，其特征在于，所述电压转换电路包括变压电路，其中，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述 第二开关管接地；
    所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
  7. 根据权利要求6所述的电压转换电路，其特征在于，所述控制单元还分别与所述第一开关管和所述第二开关管连接；
    所述控制单元，用于输出驱动信号以控制所述第一开关管和所述第二开关管；
    所述控制单元，还用于控制向所述开关单元输出的第一驱动信号由第一脉宽增至第二脉宽；
    其中，在所述第一驱动信号为所述第一脉宽时，所述第一驱动信号的相位与向所述第一开关管输出的第二驱动信号的相位互补，且与向所述第二开关管输出的第三驱动信号的相位相同；在所述第一驱动信号为所述第二脉宽时，所述开关单元为常开状态。
  8. 根据权利要求7所述的电压转换电路，其特征在于，所述控制单元用于：控制所述第一驱动信号由所述第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至所述第二脉宽。
  9. 根据权利要求8所述的电压转换电路，其特征在于，所述预设脉宽为固定值，或者，所述预设脉宽在所述变压电路启动的过程中递增。
  10. 根据权利要求7至9任一所述的电压转换电路，其特征在于，所述第一脉宽小于等于所述第一驱动信号的脉冲周期的1/2，所述第二脉宽等于所述脉冲周期。
  11. 一种电子设备，其特征在于，所述电子设备包括电压转换电路，所述电压转换电路包括变压电路，其中，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地；
    所述控制单元，用于控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路，其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时， 所述开关单元为常开。
  12. 根据权利要求11所述的电子设备，其特征在于，所述控制单元还分别与所述第一开关管和所述第二开关管连接；
    所述控制单元，用于输出驱动信号以控制所述第一开关管和所述第二开关管；
    所述控制单元，还用于控制向所述开关单元输出的第一驱动信号由第一脉宽增至第二脉宽；
    其中，在所述第一驱动信号为所述第一脉宽时，所述第一驱动信号的相位与向所述第一开关管输出的第二驱动信号的相位互补，且与向所述第二开关管输出的第三驱动信号的相位相同；在所述第一驱动信号为所述第二脉宽时，所述开关单元为常开状态。
  13. 根据权利要求12所述的电子设备，其特征在于，所述控制单元用于：控制所述第一驱动信号由所述第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至所述第二脉宽。
  14. 根据权利要求13所述的电子设备，其特征在于，所述预设脉宽为固定值，或者，所述预设脉宽在所述变压电路启动的过程中递增。
  15. 根据权利要求12至14任一所述的电子设备，其特征在于，所述第一脉宽小于等于所述第一驱动信号的脉冲周期的1/2，所述第二脉宽等于所述脉冲周期。
  16. 一种电路启动方法，其特征在于，所述方法应用于变压电路，所述变压电路包括半桥电路、谐振电路、开关单元，以及与所述开关单元连接的控制单元，其中，所述谐振电路的第一端连接到所述半桥电路中的第一开关管和第二开关管之间，所述谐振电路的第二端通过所述开关单元接地；所述第一开关管与所述变压电路的电压输入端连接，所述第二开关管接地，所述方法包括：
    所述控制单元控制所述开关单元由第一开关状态切换至第二开关状态，以启动所述变压电路；
    其中，当所述开关单元处于所述第一开关状态时，所述开关单元与所述第二开关管同步导通，且与所述第一开关管互补导通；当所述开关单元处于所述第二开关状态时，所述开关单元为常开。
  17. 根据权利要求16所述的方法，其特征在于，所述控制单元还分别与所述第一开关管和所述第二开关管连接，所述方法还包括：
    所述控制单元输出驱动信号以控制所述第一开关管和所述第二开关管；
    对应地，所述控制单元控制所述开关单元由第一开关状态切换至第二开关状态，包括：
    所述控制单元控制向所述开关单元输出的第一驱动信号由第一脉宽递增至第二脉宽；
    其中，在所述第一驱动信号为所述第一脉宽时，所述第一驱动信号的相位与向所述第一开关管输出的第二驱动信号的相位互补，且与向所述第二开关管输出的第三驱动信号的相位相同；在所述第一驱动信号为所述第二脉宽时，所述开关单元为常开状态。
  18. 根据权利要求17所述的方法，其特征在于，所述控制单元控制向所述开关单元输出的第一驱动信号由第一脉宽递增至第二脉宽，包括：
    所述控制单元控制所述第一驱动信号由所述第一脉宽每隔预设脉冲周期增加预设脉宽，直至增至所述第二脉宽。
  19. 根据权利要求18所述的方法，其特征在于，所述预设脉宽为固定值，或者，所述预设脉宽在所述变压电路启动的过程中递增。
  20. 根据权利要求17至19任一所述的方法，其特征在于，所述第一脉宽小于等于所述第一驱动信号的脉冲周期的1/2，所述第二脉宽等于所述脉冲周期。
PCT/CN2022/142711 2022-06-20 2022-12-28 变压电路、电压转换电路、电子设备和电路启动方法 WO2023246061A1 (zh)

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