CN117200594A

CN117200594A - Power adapter

Info

Publication number: CN117200594A
Application number: CN202310919605.XA
Authority: CN
Inventors: 孙程豪; 任杰; 李跃超
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2023-07-25
Filing date: 2023-07-25
Publication date: 2023-12-08

Abstract

The application provides a power adapter which comprises a first power conversion circuit, a second power conversion circuit and a first capacitor. The input end of the first power conversion circuit is used for receiving direct current, the output end of the first power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor, the input end of the second power conversion circuit is used for receiving direct current, and the output end of the second power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor; the output interface of the power adapter is used for connecting the load. The time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value or the valley value of the current charged by the first capacitor through the second power conversion circuit.

Description

Power adapter

Technical Field

The application relates to the field of terminal circuits, in particular to a power adapter.

Background

Along with the continuous development of terminal technology, the power adapter of the terminal equipment is also continuously updated, so that better experience is brought to users.

Although the power adapters of different terminal devices or electric appliances are different, the power adapters of the current terminal devices or electric appliances are relatively large in size, so that the size of the power adapters is further reduced, and the power adapters are more convenient for users to carry.

Disclosure of Invention

The application provides a power adapter, which can further reduce the volume of the power adapter, is more convenient for users to carry and brings better experience to the users.

In a first aspect, the present application provides a power adapter comprising a first power conversion circuit, a second power conversion circuit, and a first capacitor; the input end of the first power conversion circuit is used for receiving direct current, the output end of the first power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor, the input end of the second power conversion circuit is used for receiving direct current, and the output end of the second power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor; the output interface of the power adapter is used for connecting a load; the time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value or the valley value of the current charged by the first capacitor through the second power conversion circuit.

Based on the above technical scheme, by staggering the time point corresponding to the valley value of the current when the first power conversion circuit charges the first capacitor and the time point corresponding to the peak value or the valley value of the current when the second power conversion circuit charges the first capacitor, the peak value and/or the valley value of the voltage on the first capacitor can be reduced, so that the ripple voltage on the first capacitor can be reduced, the volume of the first capacitor can be reduced, and the volume of the power adapter can be correspondingly reduced along with the reduction of the volume of the first capacitor. The reduction of the volume of the power adapter is more convenient for the user to carry, and brings better experience to the user.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first power conversion circuit includes a first power conversion module, an energy transmitting coil, an energy receiving coil, and a second power conversion module, where an input end of the first power conversion module is used for receiving the direct current, an output end of the first power conversion module is connected to the energy transmitting coil, an input end of the second power conversion module is connected to the energy receiving coil, and an output end of the second power conversion module is connected to an output interface of the power adapter after being connected in parallel with the first capacitor; under the condition that the switching tubes of the first power conversion module are all in the off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

With reference to the first aspect, in some possible implementations of the first aspect, the second power conversion module includes a first rectifying bridge arm and a second rectifying bridge arm connected in parallel, and a third capacitor, each of the rectifying bridge arms includes a first rectifying diode and a second rectifying diode connected in series, one end of each of the first rectifying diodes is used for outputting direct current, one end of each of the second rectifying diodes is grounded, and a bridge arm midpoint of the first rectifying bridge arm, the third capacitor, the energy receiving coil, and a bridge arm midpoint of the second rectifying bridge arm are connected in series.

The first power conversion circuit is different from the second power conversion circuit. The first power conversion circuit comprises an energy transmitting coil and an energy receiving coil, and in a scene that the energy transmitting coil and the energy receiving coil are used separately, a load can be charged in a wireless manner by being close to the energy transmitting coil, and in the scene, the energy transmitting coil is equivalent to the output end of the first power conversion circuit, so the first power conversion circuit can be also called a wireless charging circuit; in the scenario where the energy transmitting coil and the energy receiving coil are used in combination, that is, the scenario where the present application is related, the first power conversion circuit also needs to charge the load through the output interface of the power adapter. And the second power conversion circuit can only charge the load through the output interface of the power adapter, and the second power conversion circuit can also be called a wired charging circuit.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first power conversion module includes a first switch tube and a second switch tube connected in series, a second capacitor and a first inductor, one end of the first switch tube is used for receiving direct current, one end of the second switch tube is grounded, a serial connection point of the first switch tube and the second switch tube, the second capacitor, the first inductor and the energy transmitting coil are connected in series, and one end of the energy transmitting coil is grounded; the first power conversion circuit charges the first capacitor when the first switching tube is in an on state and the second switching tube is in an off state, or when the first switching tube is in an off state and the second switching tube is in an on state; when the first switching tube and the second switching tube are in an off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first power conversion module includes a first switch bridge arm and a second switch bridge arm connected in parallel, a second capacitor and a first inductor, each switch bridge arm includes a third switch tube and a fourth switch tube connected in series, one end of each third switch tube is used for receiving direct current, one end of each fourth switch tube is grounded, and a bridge arm midpoint of the first switch bridge arm, the second capacitor, the first inductor, the energy transmitting coil and a bridge arm midpoint of the second switch bridge arm are connected in series; the first power conversion circuit charges the first capacitor when the third switching tube of the first switching bridge arm and the fourth switching tube of the second switching bridge arm are in an on state and the third switching tube of the second switching bridge arm and the fourth switching tube of the first switching bridge arm are in an off state, or when the third switching tube of the first switching bridge arm and the fourth switching tube of the second switching bridge arm are in an off state and the third switching tube of the second switching bridge arm and the fourth switching tube of the first switching bridge arm are in an on state; under the condition that the third switching tube and the fourth switching tube of each switching bridge arm are in an off state, the current of the first capacitor charged by the first power conversion circuit reaches a valley value.

In one implementation, the first power conversion module includes a first switching tube and a second switching tube connected in series, that is, the first switching tube and the second switching tube form a half-bridge structure, and the first power conversion circuit can be controlled to charge the first capacitor by controlling the on or off state switching of the first switching tube and the second switching tube. In another implementation, the first power conversion circuit includes a first switch bridge arm and a second switch bridge arm connected in parallel, each switch bridge arm includes a third switch tube and a fourth switch tube connected in series, that is, the first switch bridge arm and the second switch bridge arm form a full-bridge structure, and the first power conversion circuit can be controlled to charge the first capacitor by controlling the on or off state switching of the third switch tube and the fourth switch tube.

With reference to the first aspect, in some possible implementation manners of the first aspect, the second power conversion circuit includes a third power conversion module, a transformer, and a fourth power conversion module, an input end of the third power conversion module is used for receiving direct current, an output end of the third power conversion module is connected to a primary winding of the transformer, an input end of the fourth power conversion module is connected to a secondary winding of the transformer, and an output end of the fourth power conversion module is connected to an output interface of the power adapter after being connected in parallel with the first capacitor; in a first period, a switching tube of the third power conversion module is conducted, and the second power conversion circuit does not charge the first capacitor; in a second period, the switching tube of the third power conversion module is turned off, and the second power conversion circuit charges the first capacitor; the first period and the second period are two adjacent periods, and the current of the second power conversion circuit for charging the first capacitor reaches a peak value at the initial time point of the second period.

With reference to the first aspect, in some possible implementation manners of the first aspect, the third power conversion module includes a fifth switching tube, where one end of the fifth switching tube is used to connect to one end of the primary winding, the other end of the fifth switching tube is used to be grounded, and the other end of the primary winding is used to receive direct current; or one end of the fifth switching tube is used for receiving the direct current, the other end of the fifth switching tube is connected with one end of the primary winding, and the other end of the primary winding is grounded; when the fifth switching tube is in a conducting state, the primary winding is excited, and the second power conversion circuit does not charge the first capacitor; when the fifth switch tube is in an off state, the primary winding is demagnetized, and the second power conversion circuit charges the first capacitor.

With reference to the first aspect, in some possible implementation manners of the first aspect, the fourth power conversion module includes a sixth switching tube, one end of the sixth switching tube is connected to one end of the secondary winding of the transformer, and the other end of the sixth switching tube is connected to an output interface of the power adapter; in the first period, the fifth switching tube is in an on state, the sixth switching tube is in an off state, and the second power conversion circuit does not charge the first capacitor; and in the second period, the fifth switching tube is in an off state, the sixth switching tube is in an on state, and the second power conversion circuit charges the first capacitor.

With reference to the first aspect, in some possible implementations of the first aspect, the fourth power conversion module includes a diode, an anode of the diode is connected to one end of the secondary winding of the transformer, and a cathode of the diode is connected to an output interface of the power adapter; in the first period, the fifth switch tube is in a conducting state, and the second power conversion circuit does not charge the first capacitor; and in the second period, the fifth switch tube is in an off state, and the second power conversion circuit charges the first capacitor.

With reference to the first aspect, in certain possible implementation manners of the first aspect, the power adapter further includes a control circuit and a voltage detection circuit; the voltage detection circuit is used for: detecting output voltages of the first power conversion circuit and the second power conversion circuit; the control circuit is used for: controlling, based on output voltages of the first power conversion circuit and the second power conversion circuit, that a time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit does not coincide with a time point corresponding to a peak value of a current charged by the first capacitor through the second power conversion circuit, so that a first time point corresponding to a peak value of a current when the first capacitor is charged by the first power conversion circuit is staggered from a second time period when the first capacitor is charged by the second power conversion circuit; wherein, there is a peak value between every two valley values of the current when the first power conversion circuit charges the first capacitor.

It will be appreciated that by means of the first capacitor, the load may be supplied with energy in a stable manner, e.g. may be charged in a stable manner. The first capacitor provides energy to the load, which can be understood as the energy consumption on the first capacitor. Charging the first capacitor by the first power conversion circuit and the second power conversion circuit may be understood as the first power conversion circuit and the second power conversion circuit providing energy to the first capacitor, the voltage across the first capacitor being proportional to the energy across the first capacitor. The voltage of the first capacitor decreases when the energy consumption is greater than the energy supply, and increases when the energy consumption is less than the energy supply. To reduce the ripple voltage, the peak value of the voltage on the first capacitor may be reduced and/or the valley value of the voltage on the first capacitor may be increased. It will also be appreciated that the greater the current at which the first power conversion circuit charges the first capacitor, the faster the rate at which the first capacitor is charged.

The method can control the valley value of the current when the first power conversion circuit charges the first capacitor to fall into the second period when the second power conversion circuit charges the first capacitor, namely, the time point corresponding to the valley value of the current when the first capacitor charges through the first power conversion circuit is not overlapped with the time point corresponding to the peak value of the current when the first capacitor charges through the second power conversion circuit, in this case, the first time point corresponding to the peak value of the current when the first power conversion circuit charges the first capacitor is staggered with the second period, and the first time point corresponding to the peak value of the current when the first power conversion circuit charges the first capacitor falls into the first period when the first power conversion circuit does not charge the first capacitor, so that the peak value of the voltage on the first capacitor is reduced, the valley value of the voltage on the first capacitor is also increased, the ripple voltage of the first capacitor is reduced, and therefore the first capacitor with smaller volume can be used, and the volume of the power adapter is reduced.

With reference to the first aspect, in some possible implementations of the first aspect, the second power conversion circuit forms a buck conversion circuit or a boost conversion circuit or a buck-boost conversion circuit with the first capacitor; the input end of the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is used for receiving direct current, and the output end of the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is connected with the output interface of the power adapter; when the switching tube in the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is switched from an on state to an off state, the current of the second power conversion circuit when the first capacitor is charged reaches a peak value; when the switch tube in the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is switched from an off state to an on state, the current of the second power conversion circuit when the first capacitor is charged reaches a valley value.

With reference to the first aspect, in some possible implementations of the first aspect, the second power conversion circuit and the first capacitor form a buck conversion circuit, where the second power conversion circuit includes a primary-secondary side isolation circuit, a switching tube, a second inductor, and a diode, one end of the switching tube is connected to one end of the primary-secondary side isolation circuit, the other end of the switching tube is connected to one end of the second inductor and one end of the diode, the other end of the second inductor is connected to one end of the first capacitor, and the other end of the first capacitor and the other end of the diode are connected to the other end of the primary-secondary side isolation circuit.

With reference to the first aspect, in some possible implementations of the first aspect, the second power conversion circuit and the first capacitor form a boost conversion circuit, where the second power conversion circuit includes a primary-secondary side isolation circuit, a switching tube, a second inductor, and a diode, one end of the switching tube is connected to one end of the primary-secondary side isolation circuit and one end of the first capacitor, the other end of the switching tube is connected to one end of the second inductor and one end of the diode, one end of the second inductor is connected to one end of the diode, the other end of the second inductor is connected to the other end of the primary-secondary side isolation circuit, and the other end of the first capacitor is connected to the other end of the diode.

With reference to the first aspect, in some possible implementations of the first aspect, the second power conversion circuit and the first capacitor form a buck-boost conversion circuit, where the second power conversion circuit includes a primary-secondary side isolation circuit, a switching tube, a second inductor, and a diode, one end of the switching tube is connected to one end of the primary-secondary side isolation circuit, the other end of the switching tube is connected to one end of the second inductor and one end of the diode, the other end of the second inductor is connected to one end of the first capacitor and the other end of the primary-secondary side isolation circuit, and the other end of the first capacitor is connected to the other end of the diode.

With reference to the first aspect, in certain possible implementation manners of the first aspect, the power adapter further includes a control circuit and a voltage detection circuit; the voltage detection circuit is used for: detecting output voltages of the first power conversion circuit and the second power conversion circuit; the control circuit is used for: based on the output voltages of the first power conversion circuit and the second power conversion circuit, a first time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit is controlled not to coincide with a second time point corresponding to a valley value of a current charged by the first capacitor through the second power conversion circuit.

It will be appreciated that the greater the current output to the first capacitor, the faster the rate at which the first capacitor is charged, and the greater the peak voltage across the first capacitor, the faster the voltage across the first capacitor will rise, with the first and second power conversion circuits providing greater energy to the first capacitor than the load consumes energy across the first capacitor; similarly, the smaller the current output to the first capacitor, the slower the rate at which the first capacitor is charged, and the faster the voltage across the first capacitor drops, the smaller the valley of the voltage across the first capacitor, with the first and second power conversion circuits providing less energy to the first capacitor than the load consumes energy across the first capacitor; thus, the greater the ripple voltage across the first capacitance (i.e., the difference between the peak and valley of the voltage across the first capacitance). To reduce the ripple voltage, the peak value of the voltage of the first capacitor may be reduced and/or the valley value of the voltage of the first capacitor may be increased. Therefore, the peak value of the current for charging the first capacitor by the first power conversion circuit and the peak value of the current for charging the first capacitor by the second power conversion circuit may be shifted, the peak value of the voltage on the first capacitor may be reduced, and/or the valley value of the current for charging the first capacitor by the first power conversion circuit and the valley value of the current for charging the first capacitor by the second power conversion circuit may be shifted, the valley value of the voltage of the first capacitor may be increased, and thus the ripple voltage on the first capacitor may be reduced.

With reference to the first aspect, in some possible implementations of the first aspect, the power adapter further includes an alternating current (alternating current, AC) -Direct Current (DC) conversion circuit and a direct current-to-Direct Current (DC) conversion circuit, the input interface of the power adapter, the AC-to-DC conversion circuit and the DC-to-DC conversion circuit are connected in series, and the input of the first power conversion circuit and the input of the second power conversion circuit receive direct current from the DC-to-DC conversion circuit.

The AC-DC conversion circuit can convert alternating current input from an input interface of the power adapter into direct current, and the DC-DC conversion circuit can perform power factor correction on the direct current converted and output by the AC-DC conversion circuit.

With reference to the first aspect, in certain possible implementations of the first aspect, the control circuit includes a first control circuit and a second control circuit; the first control circuit is used for controlling the on and off of a switching tube of the first power conversion circuit; the second control circuit is used for controlling the on and off of the switching tube of the second power conversion circuit.

In a second aspect, the present application provides a chip system comprising at least one control circuit which may be used to implement the functionality involved in the control circuit in the power adapter of the first aspect and any of the possible implementations of the first aspect, e.g. to receive or process data and/or signals involved in the above-described method.

In one possible design, the chip system further includes a memory for holding program instructions and data, the memory being located within the control circuit or outside the control circuit.

The chip system may be formed of a chip or may include a chip and other discrete devices.

In a third aspect, the application provides a computer readable storage medium comprising a computer program which, when run on a computer, causes the computer to implement the first aspect and the functions involved in the control circuitry in the power adapter in any one of the possible implementations of the first aspect.

In a fourth aspect, the present application provides a computer program product comprising: a computer program (which may also be referred to as code, or instructions) which, when executed, causes a computer to perform the functions referred to by the control circuitry in the power adapter in the first aspect and any possible implementation of the first aspect.

It should be understood that the second to fourth aspects of the present application correspond to the technical solutions of the first aspect of the present application, and the advantages obtained by each aspect and the corresponding possible embodiments are similar, and are not repeated.

Drawings

FIG. 1 is a schematic circuit diagram of a power adapter according to an embodiment of the present application;

FIG. 2 is a timing diagram of the operation of a first power conversion circuit and a second power conversion circuit according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a first power conversion circuit according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a first power conversion module according to an embodiment of the present application;

FIG. 5 is a schematic diagram of another first power conversion module according to an embodiment of the present application;

FIG. 6 is a timing diagram illustrating operation of a first power conversion circuit according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a second power conversion circuit according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a third power conversion module and a fourth power conversion module according to an embodiment of the present application;

FIG. 9 is a schematic circuit diagram of another power adapter provided by an embodiment of the present application;

FIG. 10 is a timing diagram illustrating operation of another first power conversion circuit and a second power conversion circuit according to an embodiment of the present application;

FIG. 11 is a schematic diagram of another three second power conversion circuits according to an embodiment of the present application;

fig. 12 is a schematic circuit diagram of yet another power adapter provided by an embodiment of the present application.

Detailed Description

The technical scheme of the application will be described below with reference to the accompanying drawings.

In order to facilitate understanding of the embodiments of the present application, the following description is first made:

in the present application, for the sake of clarity in describing the technical solutions of the embodiments of the present application, the words "first", "second", and "third" are used to distinguish identical items or similar items having substantially identical functions and actions. For example, the first switching tube, the second switching tube, the third switching tube, etc. are only for distinguishing different switching tubes, and the first rectifying diode, the second rectifying diode, etc. are only for distinguishing different diodes, and the sequence thereof is not limited. It will be appreciated by those of skill in the art that the terms "first," "second," and "third," etc., do not denote any limitation of quantity or order of execution, and that the terms "first," "second," and "third," etc., do not denote necessarily different.

In the present application, "when … …", "in the case of … …", "if" and "if" all mean that the device will make the corresponding treatment under some objective condition, and are not limited in time, nor do it require that the device must have a judgment action when it is implemented, nor are other limitations meant to be present.

In the present application, grounding may include indirect grounding or direct grounding. The indirect grounding of a component is understood to mean that other components can be connected between the component and ground; a component is directly grounded, which is understood to mean that the component can be directly connected to ground, and no other component is present between the component and ground.

In the embodiment of the present application, the switching transistor includes, but is not limited to, a metal oxide semiconductor field effect transistor (metal oxide semiconductor field effect transistor, MOSFET), a bipolar junction transistor (bipolar junction transistor, BJT), an insulated gate bipolar transistor (insulated gate bipolar transistor, IGBT), a gallium nitride field effect transistor (gallium nitride field effect transistor, gaNFET), and the like.

Although the power adapters of different terminal devices or electric appliances are different, the volume of the power adapter of the current terminal device or electric appliance is relatively large, and how to further reduce the volume of the power adapter is convenient for users to carry is one of the problems to be solved.

One possible way to reduce the volume of the power adapter is to reduce the volume of the components in the adapter. In the power adapter, the output capacitor is a common and important component, and the size of the output capacitor is related to the size of the ripple voltage applied to the output capacitor, and the larger the ripple voltage is, the larger the required size of the output capacitor is. Therefore, in order to reduce the volume of the output capacitor in the power adapter, the ripple voltage generated by the voltage output from the power adapter can be reduced.

In order to reduce the ripple voltage applied to the output capacitor, the present application provides a power adapter, which is described in detail below with reference to the accompanying drawings.

Fig. 1 is a schematic circuit diagram of a power adapter according to an embodiment of the present application.

The power adapter shown in fig. 1 includes a first power conversion circuit, a second power conversion circuit, and a first capacitor, i.e., an output capacitor. The input end of the first power conversion circuit is used for receiving direct current, and the output end of the first power conversion circuit is connected with the output interface of the power adapter after being connected with the first capacitor in parallel. The input end of the second power conversion circuit is used for receiving direct current, and the output end of the second power conversion circuit is connected with the output interface of the power adapter after being connected with the first capacitor in parallel. The output interface of the power adapter is used for connecting a load.

The first power conversion circuit is different from the second power conversion circuit. The first power conversion circuit comprises an energy transmitting coil and an energy receiving coil, and in the scene that the energy transmitting coil and the energy receiving coil are used separately, the load can be charged in a wireless mode through being close to the energy transmitting coil. In this scenario, the energy transmitting coil corresponds to the output of the first power conversion circuit, and therefore, the first power conversion circuit may also be referred to as a wireless charging circuit. In the scenario where the energy transmitting coil and the energy receiving coil are used in combination, that is, the scenario where the present application is related, the first power conversion circuit also needs to charge the load through the output interface of the power adapter. And the second power conversion circuit can only charge the load through the output interface of the power adapter, and the second power conversion circuit can also be called a wired charging circuit.

The time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value or the valley value of the current charged by the first capacitor through the second power conversion circuit. That is, one possible implementation (for convenience of description, this implementation is referred to as a mode a) is that a point in time corresponding to a valley of a current charged by the first capacitor through the first power conversion circuit does not coincide with a point in time corresponding to a peak of the current charged by the first capacitor through the second power conversion circuit. Another possible implementation (for convenience of description, this implementation is denoted as mode B) is that a point in time corresponding to a valley of a current charged by the first capacitor through the first power conversion circuit does not coincide with a point in time corresponding to a valley of a current charged by the first capacitor through the second power conversion circuit. Both implementations can reduce ripple voltage generated after the voltages output by the first power conversion circuit and the second power conversion circuit are overlapped.

It is understood that the load may be a terminal device, such as a terminal device including, but not limited to, a cell phone, tablet, smart watch, wearable device, vehicle device, notebook, personal computer (personal computer, PC), ultra-mobile personal computer (ultra-mobile personal computer, UMPC), netbook, personal digital assistant (personal digital assistant, PDA), distributed device, and the like. The embodiment of the application does not limit the specific type of the terminal equipment.

Mode a will be described in detail below with reference to fig. 2 to 9.

Fig. 2 is a timing diagram of operation of a first power conversion circuit and a second power conversion circuit according to an embodiment of the present application.

As shown in fig. 2, in one possible implementation, the current of the input interface of the power adapter may be a pulsating direct current as shown in the first row of fig. 2, i.e. the current of the inputs of the first and second power conversion circuits may be a pulsating direct current as shown in the first row of fig. 2.

In one possible implementation, the enable signal of the first power conversion circuit may be shown in the solid line of the third row in fig. 2, where the enable signal of the first power conversion circuit is 0 at time t1 during a power supply period, for example, during a period from time t0 to time t 2; at times other than time t1, the enable signal of the first power conversion circuit is not 0. For example, as shown in the fifth row of fig. 2, at time t1, the output current of the first power conversion circuit may be 0, and the current of the first power conversion circuit charging the first capacitor reaches a valley value; at times other than time t1, the current output by the first power conversion circuit to the first capacitor is not 0, and the first power conversion circuit charges the first capacitor, for example, at time t2, the current charged by the first power conversion circuit to the first capacitor reaches a peak value. It will be appreciated that there is a peak between every two troughs of the current when the first power conversion circuit charges the first capacitor.

In one possible implementation, the enable signal of the second power conversion circuit may be as shown in the second row of fig. 2, and the second power conversion circuit does not charge the first capacitor during the period from time t0 to time t1 (i.e., during the first period); the second power conversion circuit charges the first capacitor during the period from time t1 to time t2 (i.e., during the second period). For example, as shown in the fourth row of fig. 2, the output current of the second power conversion circuit may be 0, and the second power conversion circuit does not charge the first capacitor during the period from time t0 to time t 1; at time t1, the current charged by the second power conversion circuit to the first capacitor reaches a peak value; in the period from the time t1 to the time t2, the current output to the first capacitor by the second power conversion circuit is not 0, and the second power conversion circuit charges the first capacitor; at time t2, the current charged by the second power conversion circuit to the first capacitor reaches a valley value.

It will be appreciated that by means of the first capacitor, the load may be supplied with energy in a stable manner, e.g. may be charged in a stable manner. The first capacitor provides energy to the load and can be understood as the energy consumption on the capacitor. Charging the first capacitor by the first power conversion circuit and the second power conversion circuit may be understood as the first power conversion circuit and the second power conversion circuit providing energy to the first capacitor, the voltage across the first capacitor being proportional to the energy across the first capacitor. The voltage of the first capacitor decreases when the energy consumption is greater than the energy supply, and increases when the energy consumption is less than the energy supply. For example, as shown in the sixth row in fig. 2, the second power conversion circuit does not charge the first capacitor in the period from time t0 to time t1, the first power conversion circuit charges the first capacitor, the load consumes energy on the first capacitor, the energy consumption is larger than the energy supply, and the voltage on the first capacitor gradually decreases; in the period from the time t1 to the time t2, the first power conversion circuit and the second conversion circuit charge the first capacitor, the load consumes the energy on the first capacitor, the energy consumption is smaller than the energy supply, and the voltage of the first capacitor gradually rises. It can be seen that at time t0 or time t2, the voltage of the first capacitor reaches a peak value, and at time t1, the voltage of the first capacitor reaches a valley value, and the value of the ripple voltage of the first capacitor is that is, the difference between the peak value of the first capacitor at time t0 or time t2 and the valley value of the first capacitor at time t 1.

To reduce the ripple voltage, the peak value of the voltage across the first capacitance may be reduced and/or the valley value of the voltage across the first capacitance may be increased. The enabling signal of the first power conversion circuit and the enabling signal of the second power conversion circuit can be controlled to be staggered, as shown by the dotted lines of the second row and the third row in fig. 2, the enabling signal of the first power conversion circuit is shifted backward for a period of time, so that the time point corresponding to the valley value of the current for charging the first capacitor by the first power conversion circuit is not overlapped with the time point corresponding to the peak value of the current for charging the first capacitor by the second power conversion circuit, and the valley value of the voltage of the power transmission capacity can be increased. Alternatively, when the current for charging the first capacitor by the first power conversion circuit is large, the second power conversion circuit may be controlled not to charge the first capacitor, so that the peak value of the ripple voltage on the first capacitor may be reduced. For example, the dashed line shown in the fifth row in fig. 2 corresponds to the output current of the first power conversion circuit, and the time t1 'corresponding to the valley value of the output current of the first power conversion circuit is offset from the time period (i.e., the first time period) in which the second power conversion circuit does not charge the first capacitor, so that the time t2' corresponding to the peak value of the current when the first power conversion circuit charges the first capacitor (i.e., the first time point) is offset from the time period from the time t1 to the time t2 (i.e., the second time period), and the ripple voltage of the first capacitor (as shown by the dashed line in the sixth row in fig. 2) is smaller than the ripple voltage shown by the solid line.

Fig. 3 is a schematic diagram of a first power conversion circuit according to an embodiment of the present application.

In one possible implementation, the first power conversion circuit includes a first power conversion module, an energy transmission coil, an energy reception coil, and a second power conversion module. As shown in fig. 3, the input end of the first power conversion module is used for receiving direct current, the output end of the first power conversion module is connected with the energy transmitting coil, and the input end of the second power conversion module is connected with the energy receiving coil. In addition, not shown in fig. 3, the output end of the second power conversion module is connected with the output interface of the power adapter after being connected with the first capacitor in parallel. Under the condition that the switching tubes of the first power conversion module are all in the off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

The application provides a circuit structure schematic diagram of two first power conversion modules. The following description is given with reference to fig. 4 and 5, respectively.

Fig. 4 is a schematic diagram of a first power conversion module according to an embodiment of the present application.

In one possible implementation, the first power conversion module includes a first switching tube and a second switching tube connected in series, a second capacitor, and a first inductance. As shown in fig. 4, one end of the first switching tube (e.g., Q1) is used for receiving direct current, one end of the second switching tube (e.g., Q2) is grounded, the series connection point of Q1 and Q2, the second capacitor, the first inductor and the energy transmitting coil are connected in series, and one end of the energy transmitting coil is grounded. The first power conversion circuit charges a first capacitor in a case where the Q1 is in an on state and the Q2 is in an off state, or in a case where the Q1 is in an off state and the Q2 is in an on state; with the Q1 and Q2 in the off state, the current with which the first power conversion circuit charges the first capacitor reaches a valley value. For example, as shown by a solid line in the fifth line of fig. 2, at time t1, Q1 and Q2 are in an off state, the current output to the first capacitor by the first power conversion circuit is 0, and the current charged to the first capacitor by the first power conversion circuit reaches a valley value.

Fig. 5 is a schematic diagram of another first power conversion module according to an embodiment of the present application.

In another possible implementation, the first power conversion module includes a first switching leg and a second switching leg connected in parallel, a second capacitor and a first inductor, each switching leg including a third switching tube and a fourth switching tube connected in series. One end of each third switching tube is used for receiving direct current, one end of each fourth switching tube is grounded, and the bridge arm midpoint of the first switching bridge arm, the second capacitor, the first inductor, the energy transmitting coil and the bridge arm midpoint of the second switching bridge arm are connected in series. Under the condition that a third switching tube of the first switching bridge arm and a fourth switching tube of the second switching bridge arm are in an on state and a third switching tube of the second switching bridge arm and a fourth switching tube of the first switching bridge arm are in an off state; or under the condition that the third switching tube of the first switching bridge arm and the fourth switching tube of the second switching bridge arm are in an off state and the third switching tube of the second switching bridge arm and the fourth switching tube of the first switching bridge arm are in an on state, the first power conversion circuit charges the first capacitor. Under the condition that the third switching tube and the fourth switching tube of each switching bridge arm are in an off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

As shown in fig. 5, Q3 and Q4 constitute a first switching leg, Q3 is an example of a third switching tube of the first switching leg, and Q4 is an example of a fourth switching tube of the first switching leg. Q5 and Q6 constitute a second switching leg, Q5 is an example of a third switching tube of the second switching leg, and Q6 is an example of a fourth switching tube of the second switching leg. One ends of the Q3 and the Q5 are used for receiving direct current, one ends of the Q4 and the Q6 are grounded, and the bridge arm midpoint of the first switch bridge arm, the second capacitor, the first inductor, the energy transmitting coil and the bridge arm midpoint of the second switch bridge arm are connected in series. With Q3 and Q6 in an on state and Q4 and Q5 in an off state; alternatively, the first power conversion circuit charges the first capacitor with Q3 and Q6 in an off state and Q4 and Q5 in an on state. In the case where Q3, Q4, Q5, and Q6 are in the off state, the current with which the first power conversion circuit charges the first capacitor reaches a valley value, for example, as shown by a solid line of the fifth line of fig. 2, at time t1, Q3, Q4, Q5, and Q6 are in the off state, the current output to the first capacitor by the first power conversion circuit is 0, and the current with which the first power conversion circuit charges the first capacitor reaches a valley value.

It is understood that the second capacitor and the first inductor are used to convert direct current to alternating current.

In one possible implementation manner, the second power conversion module includes a first rectifying bridge arm and a second rectifying bridge arm connected in parallel, and a third capacitor, where each rectifying bridge arm includes a first rectifying diode and a second rectifying diode connected in series, one end of each first rectifying diode is used for outputting direct current, one end of each second rectifying diode is grounded, and a bridge arm midpoint of the first rectifying bridge arm, the third capacitor, the energy receiving coil and a bridge arm midpoint of the second rectifying bridge arm are connected in series.

The second power conversion modules, D1, D2, D3 and D4, as shown in fig. 4 or fig. 5, are diodes. D1 and D2 form a first rectifying bridge arm, and D3 and D4 form a second rectifying bridge arm. D1 is an example of a first rectifying diode of the first rectifying bridge arm, D2 is an example of a second rectifying diode of the first rectifying bridge arm, D3 is an example of a second rectifying diode of the first rectifying bridge arm, and D4 is an example of a second rectifying diode of the second rectifying bridge arm. One end of each of the D1 and the D3 is used for outputting direct current, one end of each of the D2 and the D4 is grounded, and the bridge arm midpoint of the first rectifying bridge arm formed by the D1 and the D2, the third capacitor, the energy receiving coil and the bridge arm midpoint of the second rectifying bridge arm formed by the D3 and the D4 are connected in series.

Fig. 6 is a timing diagram of the operation of the first power conversion circuit according to the embodiment of the present application.

As shown in fig. 6, the dotted line shown in the first row of fig. 6 may represent the driving signal when Q1 is driven or Q3 and Q6 are driven, and the solid line shown in the first row of fig. 6 may represent the driving signal when Q2 is driven or Q4 and Q5 are driven; the solid line shown in the second row of fig. 6 may represent the current on the energy emitting coil, the dotted line shown in the second row of fig. 6 in an ascending trend may represent the excitation current of the energy emitting coil, and the dotted line shown in the second row of fig. 6 in a descending trend may represent the demagnetization current of the energy emitting coil; the solid line shown in the third row of fig. 6 may represent the voltage applied to the first capacitance.

As an example, as shown in fig. 4 and 6, in the case where Q1 is driven, that is, in the case where Q1 is turned on and Q2 is turned off, for example, in the period from time T0 to time T1, the energy transmitting coil and the energy receiving coil have currents, and the current on the energy transmitting coil is not equal to the current on the energy receiving coil, the energy transmitting coil demagnetizes, the currents on the energy transmitting coil and the energy receiving coil slowly decrease, and after the current on the energy transmitting coil becomes 0, the current direction on the energy transmitting coil changes. In this process, during the period from the time T0 to the time when the demagnetizing current of the energy transmitting coil becomes 0, D1 and D4 are turned on, D2 and D3 are turned off, and the first power conversion circuit may charge the first capacitor through D1 and D4; during this period from the time when the demagnetization current of the energy transmitting coil becomes 0 to the time T1, D1 and D4 are turned off, D2 and D3 are turned on, and the first power conversion circuit can charge the first capacitor through D2 and D3. The dead time (which is short, schematically shown at times T0, T1 and T3 in fig. 6) is when both Q1 and Q2 are in the off state, and the transmitting and receiving coils have currents, and the current on the energy transmitting coil is equal to the current on the energy receiving coil, i.e. no energy is transferred to the energy receiving coil on the energy transmitting coil during the dead time. Thus, it can be appreciated that the first power conversion circuit does not charge the first capacitor during the dead time. In the case where Q2 is driven, that is, in the case where Q1 is turned off and Q2 is turned on, for example, in the period from time T1 to time T2, the energy transmitting coil and the energy receiving coil have currents, and the current on the energy transmitting coil is not equal to the current on the energy receiving coil, the energy transmitting coil is excited, the currents on the energy transmitting coil and the energy receiving coil slowly rise, and after the current becomes 0, the current direction changes. In this process, during the period from the time T1 to the time when the exciting current of the energy transmitting coil becomes 0, D2 and D3 are turned on, D1 and D4 are turned off, and the first power conversion circuit may charge the first capacitor through D2 and D3; during this period from the time when the exciting current of the energy transmitting coil becomes 0 to the time T2, D1 and D4 are turned on, D2 and D3 are turned off, and the first power conversion circuit can charge the first capacitor through D1 and D4.

As yet another example, as shown in connection with fig. 5 and 6, in the case where Q3 and Q6 are driven, that is, in the case where Q3 and Q6 are on and Q4 and Q5 are off, for example, in the period from time T0 to time T1, the energy transmitting coil and the energy receiving coil have currents, and the currents on the energy transmitting coil and the energy receiving coil are not equal, the energy transmitting coil demagnetizes, the currents on the energy transmitting coil and the energy receiving coil slowly drop, and after the currents become 0, the current direction changes. In this process, during the period from the time T0 to the time when the demagnetizing current of the energy transmitting coil becomes 0, D1 and D4 are turned on, D2 and D3 are turned off, and the first power conversion circuit may charge the first capacitor through D1 and D4; during this period from the moment when the demagnetization current of the energy transmitting coil becomes 0 to the moment T1, D1 and D4 are turned off, D2 and D3 are turned on, and the first power conversion circuit can charge the first capacitor through D2 and D3. The dead time (the dead time is short, schematically shown at times T0, T1 and T3 in fig. 6) when Q3, Q4, Q5 and Q6 are in the off state, the transmitting coil and the receiving coil have currents, and the current on the energy transmitting coil is equal to the current on the energy receiving coil, that is, no energy is transferred from the energy transmitting coil to the energy receiving coil during the dead time. Thus, it can be appreciated that the first power conversion circuit does not charge the first capacitor during the dead time. In the case where Q4 and Q5 are driven, that is, in the case where Q3 and Q6 are off and Q4 and Q5 are on, for example, in the period from time T1 to time T2, the energy transmitting coil and the energy receiving coil have currents, and the currents on the energy transmitting coil and the energy receiving coil are not equal, the energy transmitting coil is excited, the currents on the energy transmitting coil and the energy receiving coil slowly rise, and after the currents become 0, the current direction changes. In this process, during the period from the time T1 to the time when the exciting current of the energy transmitting coil becomes 0, D2 and D3 are turned on, D1 and D4 are turned off, and the first power conversion circuit may charge the first capacitor through D2 and D3; during this period from the time when the exciting current of the energy transmitting coil becomes 0 to the time T2, D1 and D4 are turned on, D2 and D3 are turned off, and the first power conversion circuit can charge the first capacitor through D1 and D4.

It is understood that the third capacitor may be connected to ac resistor, and the first rectifying bridge arm and the second rectifying bridge arm formed by D1 to D4 may convert ac current into dc current.

Fig. 7 is a schematic diagram of a second power conversion circuit according to an embodiment of the present application.

In one possible implementation, the second power conversion circuit includes a third power conversion module, a transformer, and a fourth power conversion module. As shown in fig. 7, the input end of the third power conversion module is used for receiving direct current, the output end of the third power conversion module is connected with the primary winding of the transformer, and the input end of the fourth power conversion module is connected with the secondary winding of the transformer. In addition, not shown in fig. 7, the output end of the fourth power conversion module is connected in parallel with the first capacitor and then connected to the output interface of the power adapter.

In the first period, a switching tube of the third power conversion module is conducted, and the second power conversion circuit does not charge the first capacitor; and in the second period, the switching tube of the third power conversion module is turned off, and the second power conversion circuit charges the first capacitor. Wherein the first period and the second period are two adjacent periods. The first period may be from time t0 to time t1 as shown in fig. 2, and the second period may be from time t1 to time t2 as shown in fig. 2. The current of the second power conversion circuit charging the first capacitor reaches a peak value at a start time point of the second period.

Fig. 8 is a schematic diagram of a third power conversion module and a fourth power conversion module according to an embodiment of the present application.

In one possible implementation, the third power conversion module includes a fifth switching tube, one end of the fifth switching tube is used for connecting one end of a primary winding of the transformer, the other end of the fifth switching tube is used for grounding, and the other end of the primary winding is used for receiving direct current.

As shown in fig. 8, Q7 is an example of a fifth switching tube, one end of Q7 is connected to one end of the primary winding of the transformer, and the other end of Q7 is used for grounding.

In another possible implementation, although not shown in fig. 8, one end of the fifth switching tube may be used to receive direct current, and the other end of the fifth switching tube may be connected to one end of a primary winding of the transformer, and the other end of the primary winding of the transformer is grounded. The present application is not limited in any way.

By way of example and not limitation, in both possible implementations described above, the primary winding of the transformer is energized when the fifth switching tube is in the on state, i.e., during the first period, and the second power conversion circuit does not charge the first capacitor; when the fifth switching tube is in an off state, namely in a second period, the primary winding of the transformer is demagnetized, and the second power conversion circuit charges the first capacitor.

The present application provides circuit structure schematic diagrams of two fourth power conversion modules, and the following description will be given respectively.

In a possible implementation, the fourth power conversion module shown in fig. 8 includes a diode, where a positive pole of the diode is connected to one end of the secondary winding of the transformer, and a negative pole of the diode is connected to the output interface of the power adapter. In the first period, the fifth switching tube is in a conducting state, and the second power conversion circuit does not charge the first capacitor; and in the second period, the fifth switch tube is in an off state, and the second power conversion circuit charges the first capacitor.

In another possible implementation, although not shown in fig. 8, the fourth power conversion module includes a sixth switching tube, one end of which is connected to one end of the secondary winding of the transformer, and the other end of which is connected to the output interface of the power adapter. In the first period, the fifth switching tube is in an on state, the sixth switching tube is in an off state, and the second power conversion circuit does not charge the first capacitor; and in the second period, the fifth switching tube is in an off state, the sixth switching tube is in an on state, and the second power conversion circuit charges the first capacitor.

Fig. 8 is merely an example, and should not be construed as limiting the present application. For example, in fig. 8, a resistor is connected between Q7 and ground, that is, Q7 is indirectly grounded, and in the practical application process, Q7 and ground may not be connected, that is, Q7 may be directly grounded. As another example, in fig. 8, the second power conversion circuit may further include an absorption or resonance circuit connected between an input terminal of the second power conversion circuit and a primary winding of the transformer, which is not limited by the present application. In practical applications, the second power conversion circuit may further include other components not shown in fig. 8, which is not limited in the present application.

With respect to the detailed description of the control circuits shown in fig. 4, 5 and 8, reference may be made to the following related description, which is not repeated here for brevity.

Fig. 9 is a schematic circuit diagram of another power adapter according to an embodiment of the present application.

As shown in fig. 9, another circuit schematic of the power adapter is shown, taking the first power conversion circuit shown in fig. 5 and the second power conversion circuit shown in fig. 8 as examples.

Fig. 9 is merely an example, and should not be construed as limiting the present application. The detailed description about the first power conversion circuit may be referred to the description related to fig. 5, and the detailed description about the second power conversion circuit may be referred to the description related to fig. 8.

It will be appreciated that the fourth capacitance shown in fig. 9 may be used to stabilize the voltage flowing from the input interface. It will be further appreciated that the energy transmitting coil and the energy receiving coil in the first power conversion circuit may be used in combination or separately, and in a scenario of separate use, the load may be charged by being proximate to the energy transmitting coil, which will not be described in detail herein. The present application relates to a scenario in which an energy transmitting coil and an energy receiving coil are used in combination, i.e. both the first power conversion circuit and the second power conversion circuit charge a load through the output interface shown in fig. 9. The primary winding and the secondary winding of the transformer in the second power conversion circuit are different from the energy transmitting coil and the energy receiving coil, and the primary winding and the secondary winding of the transformer cannot be split.

By way of example and not limitation, as shown in fig. 9, the power adapter may also include an AC-DC conversion circuit and a DC-DC conversion circuit. The input interface of the power adapter, the AC-DC conversion circuit and the DC-DC conversion circuit are connected in series, and the input of the first power conversion circuit and the input of the second power conversion circuit receive direct current from the DC-DC conversion circuit. The AC-DC conversion circuit is used for converting alternating current received by the input interface of the power adapter into direct current, and the DC-DC conversion circuit can perform power factor correction on the direct current converted and output by the AC-DC conversion circuit.

Based on the first power conversion circuit and the second power conversion circuit, in one possible implementation manner, the power adapter may further include a control circuit and a voltage detection circuit; the voltage detection circuit is used for: detecting output voltages of the first power conversion circuit and the second power conversion circuit; the control circuit is used for: controlling, based on output voltages of the first power conversion circuit and the second power conversion circuit, that a time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit does not coincide with a time point corresponding to a peak value of a current charged by the first capacitor through the second power conversion circuit, so that a first time point corresponding to a peak value of the current when the first capacitor is charged by the first power conversion circuit is staggered from a second time period when the first capacitor is charged by the second power conversion circuit; wherein, there is a peak value between every two valley values of the current when the first power conversion circuit charges the first capacitor.

Illustratively, as shown by the solid or dashed line of the fifth row of fig. 2, there is a peak between every two adjacent valleys of the current at which the first power conversion circuit charges the first capacitor. As shown by the solid line in the fifth line of fig. 2, at time t2, the current at which the first power conversion circuit charges the first capacitor reaches a peak. The control circuit may control the valley value of the current when the first power conversion circuit charges the first capacitor to fall within a second period when the second power conversion circuit charges the first capacitor, that is, the point of time corresponding to the valley value of the current when the first capacitor charges the first capacitor through the first power conversion circuit does not coincide with the point of time corresponding to the peak value of the current when the first capacitor charges the second power conversion circuit, in which case, the first point of time corresponding to the peak value of the current when the first power conversion circuit charges the first capacitor is staggered from the second period, and the first point of time corresponding to the peak value of the current when the first power conversion circuit charges the first capacitor falls within a first period when the second power conversion circuit does not charge the first capacitor.

By way of example and not limitation, in one possible implementation, the voltage detection circuit may include a first voltage detection circuit and a second voltage detection circuit, and the control circuit may include a first control circuit and a second control circuit.

The first voltage detection circuit may be configured to detect a voltage across the energy-emitting coil and the second voltage detection circuit may be configured to detect output voltages of the first power conversion circuit and the second power conversion circuit.

As an example and not by way of limitation, regarding the first voltage detection circuit detecting the voltage across the energy emitting coil, the following various implementations may be included:

in one possible implementation manner, the first voltage detection circuit may be directly connected to two ends of the energy emitting coil, so as to detect the voltage at two ends of the energy emitting coil, and feed back the detected voltage at two ends of the energy emitting coil to the first control circuit, where the first control circuit feeds back the received voltage at two ends of the energy emitting coil to the DC-DC conversion circuit, and further, the DC-DC conversion circuit may adjust the output current of the DC-DC conversion circuit based on the voltage at two ends of the energy emitting coil fed back by the first control circuit, so that the output current of the DC-DC conversion circuit can meet the requirement of the first power conversion circuit.

In another possible implementation, as shown in fig. 9, the first voltage detection circuit may be connected to two ends of the second capacitor, to detect a voltage across the second capacitor, and feed back the detected voltage across the second capacitor to the first control circuit, and the first control circuit may calculate a voltage across the energy transmitting coil based on the voltage of the direct current received by the first power conversion circuit from the DC-DC conversion circuit and the voltage across the second capacitor. It will be appreciated that the sum of the voltage across the second capacitor, the voltage across the first inductor and the voltage across the energy transmitting coil is the voltage of the direct current received by the first power conversion circuit from the DC-DC conversion circuit, and since the voltage across the first inductor is negligible, the voltage across the energy transmitting coil can be calculated directly based on the voltage of the direct current received by the first power conversion circuit from the DC-DC conversion circuit and the voltage across the second capacitor. The first control circuit can feed back the calculated voltage at two ends of the received energy transmitting coil to the DC-DC conversion circuit, and then the DC-DC conversion circuit can adjust the output current of the DC-DC conversion circuit based on the voltage at two ends of the energy transmitting coil fed back by the first control circuit, so that the output current of the DC-DC conversion circuit can meet the requirement of the first power conversion circuit.

Based on the two implementations of the first voltage detection circuit for detecting the voltage across the energy emitting coil, in practical application, the first voltage detection circuit may be integrated in the first control circuit in the form of a sub-module, and the first voltage detection circuit may also be integrated in the first control circuit in the form of a sub-module, as shown in fig. 9, which is not limited in any way in the embodiment of the present application.

The first control circuit may be used to control the on and off of the switching tubes of the first power conversion circuit, and the second control circuit may be used to control the on and off of the switching tubes of the second power conversion circuit.

As shown in fig. 9, the first control circuit may cause the first power conversion circuit to charge the first capacitor by controlling on or off of Q3 to Q6. The second control circuit may be in a conducting state by controlling Q7 in a first period (for example, a period from time t0 to time t1 in fig. 2), the primary winding of the transformer is excited, no current is applied to the secondary winding, and the second power conversion circuit does not charge the first capacitor; in the second period (for example, the period from time t1 to time t2 in fig. 2), the primary winding of the transformer is demagnetized, the secondary winding of the transformer is provided with current, and the second power conversion circuit charges the first capacitor.

The first control circuit or the second control circuit may be further configured to control a first time point corresponding to a peak value of the current when the first power conversion circuit charges the first capacitor to be staggered from the second time period.

Illustratively, as shown in fig. 9, the second control circuit may be connected to one end of the second voltage detection circuit, and the other end of the second voltage detection circuit may be connected to the output ends of the first power conversion circuit and the second power conversion circuit to detect the output voltages of the first power conversion circuit and the second power conversion circuit. The second control circuit may acquire output voltages of the first power conversion circuit and the second power conversion circuit from the second voltage detection circuit.

In one implementation, the second control circuit may control, based on output voltages of the first power conversion circuit and the second power conversion circuit, that a point in time corresponding to a valley of a current charged by the first capacitor through the first power conversion circuit does not coincide with a point in time corresponding to a peak of a current charged by the first capacitor through the second power conversion circuit. The point in time at which the first control circuit controls the switching on and off of the switching transistor in the first power conversion circuit may be fixed without changing the point in time at which the switching transistor in the first power conversion circuit is turned on and off.

In another implementation manner, data interaction can be performed between the first control circuit and the second control circuit, and the first control circuit can obtain output voltages of the first power conversion circuit and the second power conversion circuit from the second control circuit, so that the first control circuit can control a time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit and a time point corresponding to a peak value of the current charged by the first capacitor through the second power conversion circuit to be not overlapped based on the output voltages of the first power conversion circuit and the second power conversion circuit. And the point in time at which the second control circuit controls the switching on and off of the switching transistor in the second power conversion circuit may be fixed without changing the point in time at which the switching transistor in the second power conversion circuit is turned on and off.

The embodiment of the application does not limit that the time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value of the current charged by the first capacitor through the second power conversion circuit, or the time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value of the current charged by the first capacitor through the second power conversion circuit.

It should be understood that fig. 9 is only an example, and should not be construed as limiting the present application.

As an example and not by way of limitation, in such an implementation, the ripple voltage on the first capacitor may be minimized in the case where the point in time corresponding to the peak value of the current with which the first power conversion circuit charges the first capacitor is infinitely close to the peak value of the current with which the second power conversion circuit charges the first capacitor, or in the case where the point in time corresponding to the valley value of the current with which the first power conversion circuit charges the first capacitor is infinitely close to the valley value of the current with which the second power conversion circuit charges the first capacitor, as the application is not limited in this regard.

Mode B will be described in detail below with reference to fig. 10 to 12.

Fig. 10 is a timing diagram illustrating operation of another first power conversion circuit and a second power conversion circuit according to an embodiment of the present application.

As shown in fig. 10, in one possible implementation, the output current of the first power conversion circuit is shown as a solid line in the second row of fig. 10, and the output current of the second power conversion circuit is shown as the first row of fig. 10, where at time t0 and time t2, the currents of the first power conversion circuit and the second power conversion circuit charging the first capacitor reach a peak value, and at time t1, the currents of the first power conversion circuit and the second power conversion circuit charging the first capacitor reach a valley value. It will be appreciated that the greater the current output to the first capacitor, the faster the rate at which the first capacitor is charged, and the faster the voltage across the first capacitor rises, the greater the peak value of the voltage across the first capacitor, with the first and second power conversion circuits providing greater energy to the first capacitor than the load consumes energy across the first capacitor; similarly, the smaller the current output to the first capacitor, the slower the rate at which the first capacitor is charged, and the faster the voltage across the first capacitor drops, the smaller the valley of the voltage across the first capacitor, with the first and second power conversion circuits supplying less energy to the first capacitor than the load consumes energy across the first capacitor; thus, the greater the ripple voltage across the first capacitance (i.e., the difference between the peak and valley of the voltage across the first capacitance).

As mentioned above, it is possible to reduce the peak value of the voltage on the first capacitor and/or to increase the valley value of the voltage on the first capacitor in order to reduce the ripple voltage. Therefore, the peak value of the current for charging the first capacitor by the first power conversion circuit and the peak value of the current for charging the first capacitor by the second power conversion circuit may be staggered, the peak value of the voltage on the first capacitor may be reduced, and/or the valley value of the current for charging the first capacitor by the first power conversion circuit and the valley value of the current for charging the first capacitor by the second power conversion circuit may be staggered, the valley value of the voltage on the first capacitor may be increased, and thus the ripple voltage on the first capacitor may be reduced. As shown by the broken line in the second row of fig. 10, a point in time corresponding to a valley value of the current for charging the first capacitor by the first power conversion circuit (for example, time t1' in fig. 10) may be controlled not to coincide with a point in time corresponding to a valley value of the current for charging the first capacitor by the second power conversion circuit (for example, time t1 in fig. 10); and/or, a point in time corresponding to a peak value of the current that the first power conversion circuit charges the first capacitor (for example, time t2' in fig. 10) may be controlled not to coincide with a point in time corresponding to a peak value of the current that the second power conversion circuit charges the first capacitor (for example, time t2 in fig. 10).

In one possible implementation, the second power conversion circuit forms a buck conversion circuit or a boost conversion circuit or a buck conversion circuit with the first capacitor; the input end of the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is used for receiving direct current, and the output end of the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is connected with the output interface of the power adapter. When the switching tube in the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is switched from an on state to an off state, the current of the second power conversion circuit when the first capacitor is charged reaches a peak value. When the switching tube in the buck conversion circuit or the boost conversion circuit or the buck conversion circuit is switched from an off state to an on state, the current of the second power conversion circuit when the first capacitor is charged reaches a valley value.

Fig. 11 is a schematic diagram of another three second power conversion circuits according to an embodiment of the application.

As shown in fig. 11, a) in fig. 11 is taken as an example of a BUCK converter circuit (e.g. a BUCK circuit), where the second power converter circuit forms a BUCK converter circuit with the first capacitor, and an input end of the second power converter circuit is used for receiving direct current, that is, an input end of the BUCK converter circuit is used for receiving direct current, and an output end of the BUCK converter circuit is used for being connected to an output interface of the power adapter. The second power conversion circuit may include a primary-secondary side isolation circuit, a switching tube (e.g., Q8), a second inductor, a diode, and the like, wherein one end of Q8 is connected to one end of the primary-secondary side isolation circuit, the other end of Q8 is connected to one end of the second inductor and one end of the diode, the other end of the second inductor is connected to one end of the first capacitor, and the other end of the first capacitor and the other end of the diode are connected to the other end of the primary-secondary side isolation circuit, that is, the primary-secondary side isolation circuit, the diode, and the first capacitor are connected in parallel.

As shown in fig. 11, b) in fig. 11 is taken as an example of a boost converter circuit, where the second power converter circuit and the first capacitor form a boost converter circuit, and an input end of the second power converter circuit is used for receiving direct current, that is, an input end of the boost converter circuit is used for receiving direct current, and an output end of the boost converter circuit is used for being connected to an output interface of the power adapter. The second power conversion circuit may include a primary-secondary side isolation circuit, a switching tube (e.g., Q9), a second inductor, a diode, and the like, where one end of the Q9 is connected to one end of the primary-secondary side isolation circuit and one end of the first capacitor, the other end of the Q9 is connected to one end of the second inductor and one end of the diode, one end of the second inductor is connected to one end of the diode, the other end of the second inductor is connected to the other end of the primary-secondary side isolation circuit, the other end of the first capacitor is connected to the other end of the diode, that is, the primary-secondary side isolation circuit is connected in parallel with the first capacitor, and the second inductor, the diode, and the first capacitor are connected in series.

As shown in fig. 11, c) in fig. 11 is taken as an example of the buck-boost converter circuit, the second power converter circuit and the first capacitor form a buck-boost converter circuit, the input end of the second power converter circuit is used for receiving the direct current, that is, the input end of the second power converter circuit is used for receiving the direct current, and the output end of the buck-boost converter circuit is used for being connected with the output interface of the power adapter. The buck-boost conversion circuit may include a primary-secondary side isolation circuit, a switching tube (e.g., Q10), a second inductor, a diode, and the like, wherein one end of Q10 is connected to one end of the primary-secondary side isolation circuit, the other end of Q10 is connected to one end of the second inductor and one end of the diode, the other end of the second inductor is connected to one end of the first capacitor and the other end of the primary-secondary side isolation circuit, and the other end of the first capacitor is connected to the other end of the diode, that is, the primary-secondary side isolation circuit, the second inductor, and the first capacitor are connected in parallel.

Wherein, not shown in fig. 11 a), b) and c), the primary-secondary side isolation circuit comprises a primary winding of the transformer and a secondary winding of the transformer, the primary-secondary side isolation circuit being used to ensure the safety of the second power conversion circuit.

It will be appreciated that the second control circuit as in fig. 11 a) or b) or c) may be used to control the switching on or off of the switching tubes of the second power conversion circuit. The detailed description may refer to the relevant content hereinafter.

By way of example and not limitation, as shown in fig. 11, the power adapter may also include an AC-DC conversion circuit and a DC-DC conversion circuit. The input interface of the power adapter, the AC-DC conversion circuit and the DC-DC conversion circuit are connected in series, and the input of the first power conversion circuit and the input of the second power conversion circuit receive direct current from the DC-DC conversion circuit. The AC-DC conversion circuit is used for converting alternating current received by the input interface of the power adapter into direct current, and the DC-DC conversion circuit can perform power factor correction on the direct current converted and output by the AC-DC conversion circuit.

In one possible implementation, the power adapter may further include a control circuit and a voltage detection circuit; the voltage detection circuit is used for: detecting output voltages of the first power conversion circuit and the second power conversion circuit; the control circuit is used for: controlling, based on output voltages of the first power conversion circuit and the second power conversion circuit, that a first time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit does not coincide with a second time point corresponding to a valley value of a current charged by the first capacitor through the second power conversion circuit; and/or the control circuit is specifically configured to control that a third time point corresponding to a peak value of the current charged by the first capacitor through the first power conversion circuit does not coincide with a fourth time point corresponding to a peak value of the current charged by the first capacitor through the second power conversion circuit.

By way of example and not limitation, in such an implementation, the ripple voltage on the first capacitance may be minimized in the event that the first point in time coincides with the fourth point in time, or the second point in time coincides with the third point in time, as the application is not limited in this regard.

As shown in fig. 12, another circuit schematic of the power adapter is shown, taking as an example the first power conversion circuit shown in fig. 5 and the second power conversion circuit shown in a) in fig. 11. Fig. 12 is merely an example, and should not be construed as limiting the present application. The detailed description about the first power conversion circuit can be referred to the description related to fig. 5, and the detailed description about the second power conversion circuit can be referred to the description related to 11.

In one possible implementation, the voltage detection circuit may include a first voltage detection circuit and a second voltage detection circuit, the control circuit may include a first control circuit and a second control circuit, the first control circuit may be used to control on and off of a switching tube of the first power conversion circuit, and the second control circuit may be used to control on and off of a switching tube of the second power conversion circuit.

Regarding the first voltage detection circuit detecting the voltage across the energy transmitting coil, reference may be made to the related description hereinabove, and for brevity, the description is omitted herein.

In one possible implementation, a voltage detection sub-module may be integrated in the second control circuit as shown in fig. 12, which may have the capability of the second voltage detection circuit shown in the figure, and may be used to detect the output voltages of the first power conversion circuit and the second power conversion circuit. In another possible implementation, not shown in fig. 12, the second voltage detection circuit may also be integrated in the second control circuit instead of being in the form of a sub-module, for example, one end of the second voltage detection circuit is connected to the first power conversion circuit and an output end of the second power conversion circuit, and the other end of the second voltage detection circuit is connected to the second control circuit, which is not limited in any way by the embodiment of the present application.

The first control circuit or the second control circuit is further configured to control the first time point to be staggered from the second time point, and/or is further configured to control the third time point to be staggered from the fourth time point.

In one implementation, after the second control circuit obtains the voltages at the output ends of the first power conversion circuit and the second power conversion circuit, the second control circuit may control the first time point to be staggered from the second time point and/or control the third time point to be misaligned from the fourth time point based on the output voltages of the first power conversion circuit and the second power conversion circuit. The point in time at which the first control circuit controls the switching on and off of the switching transistor in the first power conversion circuit may be fixed without changing the point in time at which the switching transistor in the first power conversion circuit is turned on and off.

In another implementation, data interaction may be performed between the first control circuit and the second control circuit, and the first control circuit may obtain output voltages of the first power conversion circuit and the second power conversion circuit from the second control circuit, so that the first control circuit may control the first time point to be staggered from the second time point and/or control the third time point to be misaligned from the fourth time point based on the output voltages of the first power conversion circuit and the second power conversion circuit. And the point in time at which the second control circuit controls the switching on and off of the switching transistor in the second power conversion circuit may be fixed without changing the point in time at which the switching transistor in the second power conversion circuit is turned on and off.

It is to be understood that fig. 12 is only an example and should not be construed as limiting the application in any way.

Based on the above scheme, by staggering the time point corresponding to the valley value of the current when the first power conversion circuit charges the first capacitor and the time point corresponding to the peak value or the valley value of the current when the second power conversion circuit charges the first capacitor, the peak value and/or the valley value of the voltage on the first capacitor can be reduced, so that the ripple voltage on the first capacitor can be reduced, the volume of the first capacitor can be reduced, and the volume of the power adapter can be correspondingly reduced along with the reduction of the volume of the first capacitor. The reduction of the volume of the power adapter is more convenient for the user to carry, and brings better experience to the user.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A power adapter, wherein the power adapter comprises a first power conversion circuit, a second power conversion circuit and a first capacitor; the input end of the first power conversion circuit is used for receiving direct current, the output end of the first power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor, the input end of the second power conversion circuit is used for receiving the direct current, and the output end of the second power conversion circuit is connected with the output interface of the power adapter after being connected in parallel with the first capacitor; the output interface of the power adapter is used for connecting a load; wherein,

the time point corresponding to the valley value of the current charged by the first capacitor through the first power conversion circuit is not overlapped with the time point corresponding to the peak value or the valley value of the current charged by the first capacitor through the second power conversion circuit.

2. The power adapter of claim 1 wherein the first power conversion circuit comprises a first power conversion module, an energy transmitting coil, an energy receiving coil, and a second power conversion module, wherein an input of the first power conversion module is configured to receive the direct current, an output of the first power conversion module is connected to the energy transmitting coil, an input of the second power conversion module is connected to the energy receiving coil, and an output of the second power conversion module is connected to an output interface of the power adapter in parallel with the first capacitor;

and under the condition that the switching tubes of the first power conversion module are all turned off, the first power conversion circuit charges the first capacitor to a valley value.

3. The power adapter of claim 2 wherein the second power conversion module comprises first and second rectifying legs connected in parallel, and a third capacitor, each of the rectifying legs comprising first and second rectifying diodes connected in series, one end of each of the first rectifying diodes being configured to output dc power, one end of each of the second rectifying diodes being grounded, the bridge midpoint of the first rectifying leg, the third capacitor, the energy receiving coil, and the bridge midpoint of the second rectifying leg being connected in series.

4. A power adapter according to claim 2 or 3, wherein the first power conversion module comprises a first switching tube and a second switching tube connected in series, a second capacitor and a first inductor, one end of the first switching tube is used for receiving direct current, one end of the second switching tube is grounded, a series connection point of the first switching tube and the second switching tube, the second capacitor, the first inductor and the energy transmitting coil are connected in series, and one end of the energy transmitting coil is grounded;

the first power conversion circuit charges the first capacitor when the first switching tube is in an on state and the second switching tube is in an off state, or when the first switching tube is in an off state and the second switching tube is in an on state; and under the condition that the first switching tube and the second switching tube are in an off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

5. A power adapter according to claim 2 or 3, wherein the first power conversion module comprises a first switch leg and a second switch leg connected in parallel, a second capacitor and a first inductor, each of the switch legs comprises a third switch tube and a fourth switch tube connected in series, one end of each of the third switch tubes is used for receiving direct current, one end of each of the fourth switch tubes is grounded, and a leg midpoint of the first switch leg, the second capacitor, the first inductor, the energy transmitting coil and a leg midpoint of the second switch leg are connected in series;

The first power conversion circuit charges the first capacitor when the third switching tube of the first switching bridge arm and the fourth switching tube of the second switching bridge arm are in an on state and the third switching tube of the second switching bridge arm and the fourth switching tube of the first switching bridge arm are in an off state, or when the third switching tube of the first switching bridge arm and the fourth switching tube of the second switching bridge arm are in an off state and the third switching tube of the second switching bridge arm and the fourth switching tube of the first switching bridge arm are in an on state; and under the condition that the third switching tube and the fourth switching tube of each switching bridge arm are in an off state, the current of the first power conversion circuit for charging the first capacitor reaches a valley value.

6. The power adapter of any one of claims 1 to 5 wherein the second power conversion circuit comprises a third power conversion module, a transformer, and a fourth power conversion module, an input of the third power conversion module being configured to receive direct current, an output of the third power conversion module being connected to a primary winding of the transformer, an input of the fourth power conversion module being connected to a secondary winding of the transformer, an output of the fourth power conversion module being connected in parallel with the first capacitor and then being connected to an output interface of the power adapter;

In a first period, a switching tube of the third power conversion module is conducted, and the second power conversion circuit does not charge the first capacitor;

and in a second period, the switching tube of the third power conversion module is turned off, the second power conversion circuit charges the first capacitor, wherein the first period and the second period are two adjacent periods, and the current charged by the second power conversion circuit to the first capacitor reaches a peak value at the starting time point of the second period.

7. The power adapter of claim 6 wherein said third power conversion module comprises a fifth switching tube, one end of said fifth switching tube being adapted to connect to one end of said primary winding, the other end of said fifth switching tube being adapted to be grounded, the other end of said primary winding being adapted to receive direct current; or,

one end of the fifth switching tube is used for receiving the direct current, the other end of the fifth switching tube is connected with one end of the primary winding, and the other end of the primary winding is grounded;

when the fifth switching tube is in a conducting state, the primary winding is excited, and the second power conversion circuit does not charge the first capacitor; and when the fifth switching tube is in an off state, the primary winding is demagnetized, and the second power conversion circuit charges the first capacitor.

8. The power adapter of claim 7 wherein the fourth power conversion module comprises a sixth switching tube, one end of the sixth switching tube being connected to one end of the secondary winding of the transformer, the other end of the sixth switching tube being connected to an output interface of the power adapter;

in the first period, the fifth switching tube is in an on state, the sixth switching tube is in an off state, and the second power conversion circuit does not charge the first capacitor; the method comprises the steps of,

and in the second period, the fifth switching tube is in an off state, the sixth switching tube is in an on state, and the second power conversion circuit charges the first capacitor.

9. The power adapter of claim 7 wherein the fourth power conversion module comprises a diode, the anode of the diode being connected to one end of the secondary winding of the transformer, the cathode of the diode being connected to the output interface of the power adapter;

in the first period, the fifth switching tube is in a conducting state, and the second power conversion circuit does not charge the first capacitor; the method comprises the steps of,

And in the second period, the fifth switching tube is in an off state, and the second power conversion circuit charges the first capacitor.

10. The power adapter according to any one of claims 1 to 9, further comprising a control circuit and a voltage detection circuit;

the voltage detection circuit is used for: detecting output voltages of the first power conversion circuit and the second power conversion circuit;

the control circuit is used for: controlling on and off of switching transistors of the first power conversion circuit and the second power conversion circuit based on output voltages of the first power conversion circuit and the second power conversion circuit, so that a time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit is not overlapped with a time point corresponding to a peak value of the current charged by the first capacitor through the second power conversion circuit, and a first time point corresponding to the peak value of the current when the first capacitor is charged by the first power conversion circuit is staggered with a second time period when the first capacitor is charged by the second power conversion circuit; wherein, there is a peak value between every two valley values of the current when the first power conversion circuit charges the first capacitor.

11. The power adapter of any one of claims 1 to 5 wherein the second power conversion circuit forms a buck conversion circuit or a boost conversion circuit or a buck-boost conversion circuit with the first capacitor; the input end of the buck conversion circuit or the boost conversion circuit or the buck-boost conversion circuit is used for receiving the direct current, and the output end of the buck conversion circuit or the boost conversion circuit or the buck-boost conversion circuit is connected with the output interface of the power adapter; when a switching tube in the buck conversion circuit or the boost conversion circuit or the buck-boost conversion circuit is switched from an on state to an off state, a current of the second power conversion circuit when the first capacitor is charged reaches a peak value; when the switching tube in the buck conversion circuit or the boost conversion circuit or the buck-boost conversion circuit is switched from an off state to an on state, the current when the second power conversion circuit charges the first capacitor reaches a valley value.

12. The power adapter of claim 11 wherein the second power conversion circuit forms a buck conversion circuit with the first capacitor, wherein the second power conversion circuit includes a primary-secondary side isolation circuit, a switching tube, a second inductor, and a diode, one end of the switching tube being connected to one end of the primary-secondary side isolation circuit, the other end of the switching tube being connected to one end of the second inductor and one end of the diode, the other end of the second inductor being connected to one end of the first capacitor, the other end of the first capacitor and the other end of the diode being connected to the other end of the primary-secondary side isolation circuit.

13. The power adapter of claim 11 or 12, further comprising a control circuit and a voltage detection circuit;

the control circuit is used for: and controlling a first time point corresponding to a valley value of a current charged by the first capacitor through the first power conversion circuit to be not overlapped with a second time point corresponding to a valley value of a current charged by the first capacitor through the second power conversion circuit based on output voltages of the first power conversion circuit and the second power conversion circuit.

14. The power adapter of any one of claims 1 to 13, further comprising an ac-dc conversion circuit and a dc-dc conversion circuit, wherein an input interface of the power adapter, the ac-dc conversion circuit, and the dc-dc conversion circuit are connected in series, and wherein an input of the first power conversion circuit and an input of the second power conversion circuit receive dc power from the dc-dc conversion circuit.

15. The power adapter of claim 10 or 13, wherein the control circuit comprises a first control circuit and a second control circuit;

the first control circuit is used for controlling the on and off of a switching tube of the first power conversion circuit;

the second control circuit is used for controlling the on and off of a switching tube of the second power conversion circuit.