Wireless power receiving circuit, wireless charging device and system

Abstract

Embodiments of the present invention provide a radio power receiving circuit including a power receiving coil, a matching circuit, a rectifier circuit, a controller, and an output terminal, wherein the rectifier circuit includes at least one switching unit. The power receiving coil is configured to receive energy and output an alternating current. The matching circuit is configured to perform matching to the alternating current and to transmit the alternating current to the input terminal of the rectifier circuit. The rectifier circuit is configured to convert the input alternating current to direct current. The controller is configured to determine the duty cycle of at least one switching unit based on the output voltage of the voltage output terminal and to control the turn-on or turn-off of at least one switching unit based on the duty cycle to perform voltage regulation with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the radio power receiving circuit.

Description

Technical Field

[0001] Embodiments of the present application relate to the fields of electronic devices and wireless charging, and more specifically, to wireless power receiving circuits, wireless charging devices, and systems.

Background Art

[0002] The power limits of mobile or portable wireless charging devices such as mobile phones are gradually increasing. Therefore, in order to improve the user's charging experience, it is necessary to increase the wireless charging power to shorten the charging time. However, since the heat dissipation capacity of the terminal device is limited, it is necessary to further improve the efficiency of the power receiving end of wireless charging in order to support higher wireless charging power.

[0003] In the prior art, the output voltage is adjusted by pulse modulation. However, the modulation frequency of pulse modulation is generated based on the main frequency of wireless charging, and the main frequency needs to be detected. Therefore, continuous voltage adjustment is not supported.

Summary of the Invention

Means for Solving the Problems

[0004] The present application provides a wireless power receiving circuit, a wireless charging device, and a system for performing continuous voltage adjustment.

[0005] According to a first aspect, the application provides a radio power receiving circuit including a power receiving coil, a matching circuit, a rectifier circuit, a controller, and an output terminal, wherein the rectifier circuit includes at least one switching unit. The power receiving coil is configured to receive energy and output an alternating current. The matching circuit is configured to perform matching to the alternating current and to transmit the alternating current to the input terminal of the rectifier circuit. The rectifier circuit is configured to convert the input alternating current to direct current. The controller is configured to determine the duty cycle of at least one switching unit based on the output voltage of the voltage output terminal and to control the turn-on or turn-off of at least one switching unit based on the duty cycle to perform voltage adjustment to the output voltage, wherein the duty cycle is independent of the main frequency of the radio power receiving circuit.

[0006] Since the duty cycle is independent of the main frequency of the wireless power receiving circuit, the duty cycle does not have to be an integer multiple of the main frequency. Therefore, if the output voltage changes continuously, the duty cycle also changes continuously at the same time.

[0007] Voltage adjustment may also be a boost adjustment.

[0008] In existing implementations, the main frequency must be detected to perform voltage regulation, and the determined duty cycle of the switching transistor is an integer multiple of the main frequency. Therefore, continuous voltage regulation cannot be performed. In this application, from the viewpoint of hardware structure, voltage regulation operation can be performed without using an additional voltage regulator, the duty cycle is independent of the main frequency of the wireless power receiving circuit, and as a result, continuous voltage regulation can be performed without the need to detect the main frequency.

[0009] In possible implementations, the duty cycle is not an integer multiple of the principal frequency.

[0010] In possible implementations, when the output voltage changes continuously, the duty cycle also changes continuously.

[0011] In possible implementations, the rectifier circuit further includes a rectifier bridge, which includes multiple diodes, and each switching unit is connected in parallel to one of the diodes.

[0012] In a possible implementation, at least one switching unit includes only the first switching unit.

[0013] In a possible implementation, at least one switching unit includes a first switching unit and a second switching unit, and the plurality of diodes include high-side diodes and low-side diodes. Both the first and second switching units are connected in parallel to the low-side diode, or both the first and second switching units are connected in parallel to the high-side diode, or the first switching unit is connected in parallel to the low-side diode and the second switching unit is connected in parallel to the high-side diode, and the first and second switching units are not directly connected.

[0014] Please understand that the diode and switching unit may be a 2-in-1 component, or a combination of a diode and a switching transistor.

[0015] In a possible implementation, the step of controlling the on or off of at least one switching unit includes the step of controlling the first switching unit and the second switching unit to be turned on or off simultaneously.

[0016] In possible implementations, the rectifier circuit further includes a rectifier bridge, which includes a plurality of controllable switching transistors, each containing at least one switching unit.

[0017] In a possible implementation, at least one switching unit includes only the first switching unit.

[0018] In a possible implementation, at least one switching unit includes a first switching unit and a second switching unit.

[0019] Both the first switching unit and the second switching unit are low-side controllable switching transistors, or Both the first switching unit and the second switching unit are high-side controllable switching transistors, or The first switching unit is a low-side controllable switching transistor, and the second switching unit is a high-side controllable switching transistor; the first switching unit and the second switching unit are not directly connected. In a possible implementation, the step of controlling the on or off of at least one switching unit includes the step of controlling the first switching unit and the second switching unit to be turned on or off simultaneously.

[0020] According to a second aspect, the present application provides a radio power receiving circuit including a power receiving coil, a detuning circuit, a rectifier circuit, a controller, and an output terminal, wherein the detuning circuit includes a matching circuit and a grounded target branch, the matching circuit being connected to the target branch, and the target branch including a detuning capacitor and a switching unit. The power receiving coil is configured to receive energy and output an alternating current. The rectifier circuit is configured to convert the input alternating current to direct current. The controller is configured to determine the duty cycle of the switching unit based on the output voltage of the voltage output terminal and to control the turn-on or turn-off of the switching unit based on the duty cycle to perform voltage adjustment with respect to the output voltage, the duty cycle being independent of the main frequency of the radio power receiving circuit.

[0021] This is equivalent to the detuning capacitor and the switching transistor being directly connected in series between the matching circuit 505 and the ground. The controller 503 generates a modulation signal S2 that is independent of the main frequency of the wireless charging to control the on / off of the switch and performs step-down control.

[0022] The voltage adjustment may be step-down adjustment.

[0023] In a possible implementation, the duty cycle is not an integer multiple of the main frequency.

[0024] In a possible implementation, when the output voltage changes continuously, the duty cycle changes continuously at the same time.

[0025] In a possible implementation, the matching capacitor includes a first capacitor and a second capacitor. The first capacitor and the second capacitor are located at the first end of the power receiving coil. The target branch includes a first branch and a second branch. The first branch includes a first detuning capacitor and a first switching unit. The second branch includes a second detuning capacitor and a second switching unit. The first branch is connected between the node between the first capacitor and the second capacitor and the ground. The second branch is connected between the node at the second end of the power receiving coil and the ground.

[0026] It should be understood that the matching capacitor includes at least a first capacitor and may be a plurality of capacitors (for example, a first capacitor and a second capacitor).

[0027] The target branch may include at least a first branch and may be a plurality of branches (for example, a first branch and a second branch), and usually one or two branches.

[0028] In a possible implementation, the step of controlling the on or off of the switching unit includes the step of controlling to turn on or off the first switching unit and the second switching unit simultaneously.

[0029] According to a third aspect, the present application provides a wireless charging device including a wireless power receiving circuit according to any one of the first aspect or the second aspect and an energy storage device. The wireless power receiving circuit is configured to function as a power receiving end of wireless charging. The wireless power receiving circuit is configured to receive electrical energy and transmit the electrical energy to the energy storage device.

[0030] According to a fourth aspect, the present application provides a charging system including a wireless charging device according to the fourth aspect and a wireless charging device.

[0031] According to a fifth aspect, the present application provides a wireless charging control method applied to a power receiving end of wireless charging. The power receiving end includes a power receiving coil, a matching circuit, a rectifying circuit, a controller, and an output end, and the rectifying circuit includes at least one switching unit.

[0032] The method includes determining a duty cycle of the at least one switching unit based on an output voltage of the voltage output end, and controlling the turn-on or turn-off of the at least one switching unit based on the duty cycle to perform voltage adjustment on the output voltage, wherein the duty cycle is independent of a main frequency of the wireless power receiving circuit.

[0033] In a possible implementation, the duty cycle is not an integer multiple of the main frequency.

[0034] In a possible implementation, when the output voltage changes continuously, the duty cycle changes continuously at the same time.

[0035] According to a sixth aspect, the present application provides a wireless charging control method applicable to the receiving end of wireless charging. The receiving end includes a receiving coil, a detuning circuit, a rectifier circuit, a controller, and an output end, the detuning circuit includes a matching circuit and a grounded target branch, the matching circuit is connected to the target branch, and the target branch includes a detuning capacitor and a switching unit.

[0036] The aforementioned method, The process includes determining the duty cycle of the switching unit based on the output voltage of the voltage output terminal, and controlling the turn-on or turn-off of the switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit.

[0037] In possible implementations, the duty cycle is not an integer multiple of the principal frequency.

[0038] In possible implementations, when the output voltage changes continuously, the duty cycle also changes continuously. [Brief explanation of the drawing]

[0039] [Figure 1] This is a diagram of a wireless charging system to which the present invention can be applied. [Figure 2] This is a schematic diagram of several wireless reverse charging scenes according to embodiments of the present invention. [Figure 3] This is a diagram of another wireless charging system according to an embodiment of the present application. [Figure 4] This is a diagram illustrating the principle of wireless charging. [Figure 5] This is a diagram showing the circuit configuration. [Figure 6] This is a diagram showing the circuit configuration. [Figure 7] A diagram of the circuit structure. [Figure 8] This is a diagram of the duty cycle. [Modes for carrying out the invention]

[0040] The following describes the technical solutions in the embodiments of this application with reference to the attached drawings.

[0041] In the description of embodiments of this application, unless otherwise specified, " / " represents an "or" relationship. For example, A / B may represent A or B. In this specification, "and / or" is merely a relation to describe the related subjects and indicates that there may be three possible relationships. For example, A and / or B may represent the following three cases: when only A exists, when both A and B exist, or when only B exists.

[0042] In the embodiments of this application, the terms “first” and “second” are used solely for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features being referred to. Therefore, features limited by “first” or “second” may explicitly or implicitly include one or more such features. In addition, in the description of the embodiments of this application, “multiple” means two or more, and “at least one” and “one or more” mean one, two, or more. The singular forms “one,” “a,” “that,” “the,” “the preceding,” “this,” and “the one” are also intended to include forms such as “one or more,” unless explicitly specified otherwise in the context.

[0043] References to “embodiments,” “some embodiments,” etc., described herein mean that one or more embodiments of this application include certain features, structures, or characteristics described by reference to the embodiments. Accordingly, phrases such as “in one embodiment,” “in some embodiments,” “in some other embodiments,” and “in other embodiments,” appearing elsewhere in this specification, do not necessarily mean that they refer to the same embodiment. Instead, these phrases mean “one or more embodiments, but not all of them,” unless otherwise specifically emphasized. The terms “include,” “contain,” “have,” and other variations thereof all mean “include, but not limited to,” unless otherwise specifically emphasized.

[0044] In the description of embodiments of this application, orientations or positional relationships indicated by terms such as “up,” “down,” “left,” “right,” “inside,” “outside,” “vertical,” and “horizontal” are defined in relation to the orientation or position of components schematically arranged in the accompanying drawings. It should be understood that these directional terms are relative concepts and are used for relative description and clarification, and do not indicate or imply that a particular device or component must have a particular orientation, or is constructed and operated in a particular orientation. The terminology may change correspondingly based on changes in the orientation of components arranged in the accompanying drawings and should therefore not be understood as limitations on this application. Furthermore, “vertical” in this application means perpendicular within tolerance, not strictly perpendicular. “Parallel” means parallel within tolerance, not parallel in the strict sense.

[0045] In the embodiments of this application, the same reference numeral indicates the same component or part. For the same component or part in the embodiments of this application, only one component or part may be marked by a reference numeral in the drawings as an example. It should be understood that this also applies to the reference numerals of other identical components or parts. Furthermore, the parts or parts in the drawings are not depicted to actual scale. The dimensions and sizes of the components or parts shown in the drawings are merely examples and should not be understood as limitations of this application.

[0046] Figure 1 is a diagram of a wireless charging system to which this application can be applied.

[0047] As shown in Figure 1, the wireless charging system 100 may include a wireless charging power transmission device 110 and a wireless charging power receiving device 120. Energy can be transmitted between the wireless charging power transmission device 110 and the wireless charging power receiving device 120 in an energy coupling manner. More specifically, the wireless charging power transmission device 110 is used as an energy source and can charge the wireless charging power receiving device 120 by using the principle of electromagnetic induction.

[0048] In some embodiments, the wireless charging power transmission device 110 used as a charging device is also called the transmission end, and the wireless charging power receiving device 120 used as a power receiving device is also called the receiving end.

[0049] In the embodiments of this application, the wireless charging power transmission device 110 or the wireless charging power reception device 120 may be a device having a wireless charging function, such as a smartphone, smartwatch, smart band, stylus, earphone, charging case, tablet computer, electronic reader, notebook computer, camera, in-vehicle device, wireless charger, mobile charger (also known as mobile power supply or power bank), wearable device (e.g., smart glasses or smart jewelry), virtual reality (VR) terminal device, augmented reality (AR) terminal device, smart home device (e.g., smart screen or smart TV), or vehicle.

[0050] As an example, and not an exhaustive list, the wireless charging transmitter 110 may be a charging cradle and the wireless charging receiver 120 may be a mobile phone, or the wireless charging transmitter 110 may be a charging case and the wireless charging receiver 120 may be wireless earphones, or the wireless charging transmitter 110 may be a smartphone and the wireless charging receiver 120 may be a smartwatch, or the wireless charging transmitter 110 may be a vehicle, and the wireless charging receiver 120 may be a portable electronic device such as a mobile phone or tablet computer.

[0051] In some embodiments, the wireless charging system 100 may further include a charger 130, which is connected to a wireless charging power transmission device 110. The charger 130 may be configured to receive commercial power, convert the commercial power to DC, and output the DC to the wireless charging power transmission device 110. Alternatively, the charger 130 may be configured to output the received AC commercial power directly to the wireless charging power transmission device 110. The wireless charging power transmission device 110 is configured to convert the received electrical energy into electromagnetic field energy and transmit the electromagnetic field energy to the outside. The wireless charging power receiving device 120 is configured to receive the electromagnetic field energy, convert the electromagnetic field energy into electrical energy, and perform wireless charging.

[0052] In some embodiments, the wireless charging system 100 may further include an energy device 140, such as a battery. The wireless charging power transmission device 110 may be directly connected to the energy device 140 and receive direct current or alternating current provided by the energy device 140 as input.

[0053] In some embodiments, the wireless charging receiver 120 can also be used as an energy source to charge another device that supports wireless charging. For example, a mobile phone with wireless charging capabilities may charge a device that supports wireless charging, such as earphones, a watch, or another mobile phone. In other words, the wireless charging receiver 120 can receive electrical energy provided by the wireless charging transmitter 110 and can also be used as a wireless charging transmitter to charge another wireless charging receiver, i.e., it can support wireless reverse charging functionality. Unlike the power supply method of wireless charging cradles, the energy for wireless reverse charging relies mainly on the device battery, and the charging power is low.

[0054] It should be noted that the phrase "the device has a wireless charging function" or similar description in this application may be understood as the device having the ability to wirelessly transmit power to another device, and / or the device having the ability to wirelessly receive power transmitted by another device. That is, the device may be the transmitting end and / or the receiving end.

[0055] It should be noted that the phrase "the device has a wireless reverse charging function" or similar description in this application may be understood as the device having the ability to wirelessly receive power transmitted by another device and the ability to wirelessly transmit power to another device.

[0056] Figure 2 illustrates several wireless reverse charging scenarios according to one embodiment of the present application. It should be understood that the specific forms of wireless reverse charging scenarios are not limited to the embodiments of the present application. The wireless reverse charging scenarios described in Figure 2 are merely some examples provided for ease of understanding.

[0057] As shown in Figure 2(a), the wireless reverse charging scenario may include a mobile phone 121 and a wristwatch 151. The mobile phone 121 may be used as the receiving end for receiving electrical energy in the wireless charging process. Furthermore, the mobile phone 121 may be used as the transmitting end for performing wireless reverse charging to the wristwatch 151 after the wireless reverse charging function has been enabled. In this case, the wristwatch 151 is the receiving end in the wireless reverse charging process.

[0058] As shown in Figure 2(b), the wireless reverse charging scenario may include a mobile phone 122 and an earphone charging case 152. The mobile phone 122 may be used as the receiving end to receive electrical energy in the wireless charging process. Alternatively, the mobile phone 122 may be used as the transmitting end to wirelessly reverse charge the earphone charging case 152 after the wireless reverse charging function has been enabled. In this case, the earphone charging case 152 is the receiving end in the wireless reverse charging process.

[0059] As shown in Figure 2(c), the wireless reverse charging scenario may include a first mobile phone 123 and a second mobile phone 153. The first mobile phone 123 may be used as a receiving end to receive electrical energy in the wireless charging process. In addition, the first mobile phone 123 may be used as a transmitting end to perform wireless reverse charging to the second mobile phone 153 after the wireless reverse charging function has been enabled. In this case, the second mobile phone 153 is the receiving end in the wireless reverse charging process.

[0060] As shown in Figure 2(d), the wireless reverse charging scenario may include a tablet computer 124 and a stylus 154. The tablet computer 124 may be used as the receiving end for receiving electrical energy in the wireless charging process. In addition, the tablet computer 124 may be used as the transmitting end for performing wireless reverse charging on the stylus 154 after the wireless reverse charging function has been enabled. In this case, the stylus 154 is the receiving end in the wireless reverse charging process.

[0061] In Figures 2(a) to (d), the wristwatch 151, the earphone charging case 152, the second mobile phone 153, and the stylus 154 may not have a wireless reverse charging function, or the wireless reverse charging function may not be temporarily enabled.

[0062] It should be understood that the specific type of device in a wireless reverse charging scenario is not limited to the embodiments of the present application. For example, the power supply device (i.e., the electronic device that enables the wireless reverse charging function and wirelessly charges another device) may be a portable electronic device, such as a mobile phone, tablet computer, or notebook computer. The power receiving device (i.e., the electronic device that is wirelessly charged by the charging device) may be a portable electronic device, such as a mobile phone, band, watch, earphone, keyboard, stylus, or electric toothbrush.

[0063] In addition, it can be understood that the wireless reverse charging scenario is one of the wireless charging scenarios. Accordingly, Figures 2(a) to 2(d) are, in fact, specific examples of the wireless charging system 100. Mobile phones 121, 122, the first mobile phone 123, and the tablet computer 124 are specific examples of the wireless charging power transmission device 110 shown in Figure 1. The wristwatch 151, the earphone charging case 152, the second mobile phone 153, and the stylus 154 are specific examples of the wireless charging power receiving device 120 shown in Figure 1.

[0064] Figure 3 shows another wireless charging system 100 according to one embodiment of the present invention. In the embodiment shown in Figure 3, an example is used for illustrative purposes in which the wireless charging power transmission device 110 is a glasses case and the wireless charging power receiving device 120 is smart glasses.

[0065] The wireless charging power transmission device 110 may include a housing 111 and a wireless power receiving circuit 113. The wireless power receiving circuit 113 may be fixed to the housing 111, for example, to the inner wall of the housing 111. The housing 111 may be further configured to house eyeglasses, for example, the wireless charging power receiving device 120 shown in Figure 3.

[0066] The wireless charging receiver 120 may include a frame 123, temples 124, and lenses 125. There may be one or more temples 124. In the embodiment shown in Figure 3, there may be multiple temples 124. The lenses 125 are fixed to the frame 123.

[0067] One end of the temple 124 may be rotatably connected to the other end of the frame 123 via a connecting shaft, thereby allowing the temple 124 to be switched between an extended and a folded state. In some embodiments, one end of the temple 124 may be detachably connected to the other end of the frame 123 via a connecting shaft. When the temple 124 is in the extended state, it can be worn on the user's ear. Figure 3 shows the temple 124 in the folded state. When the temple 124 is in the folded state, it folds relative to the frame 123. In some embodiments, the folded temple 124 facilitates the housing of the smart glasses 100 in a glasses case (e.g., the wireless charging power transmission device 110 shown in Figure 3, or a general glasses case).

[0068] Electronic devices (not shown), such as a main board, a wireless power receiving circuit 122, or a battery, may be located on the temple 124. A voice control module, a gesture recognition module, an eye-tracking module, etc., may be located on the main board. As a power source, a battery may supply electrical energy to the temple 124. The wireless power receiving circuit 122 may include a receiving coil, and the wireless power receiving circuit 122 can charge the battery via the receiving coil. In some embodiments, the battery may be located at the end of the temple away from the frame, and the wireless power receiving circuit 122 and the main board may be located at the end of the temple closer to the frame.

[0069] In some possible scenarios, the smart glasses may be augmented reality (AR) smart glasses. When the smart glasses are worn on the user's head, the user can see images displayed by the smart glasses' display unit (not shown). In other words, the user can not only view real-world scenarios through the smart glasses, but also observe images of a virtual world through the smart glasses. In some embodiments, the user may further use the smart glasses so that they display virtual images to enhance the real-world observation effect. In some other possible scenarios, the smart glasses may not be limited to AR smart glasses, and the smart glasses may be other smart glasses, such as VR smart glasses that implement virtual reality (VR) effects, smart glasses that implement mixed reality (MR) effects, or smart glasses with audio capabilities.

[0070] Referring to the wireless charging system 100 shown in Figures 1, 2, and 3, the principle of wireless charging from the wireless charging transmission device 110 to the wireless charging receiving device 120 will be explained below.

[0071] In the process of wirelessly charging the wireless charging receiving device 120 using a wireless charging power transmission device 110, the wireless charging power transmission device 110 may be located in close proximity to the wireless charging receiving device 120, thereby allowing the power transmission coil of the wireless charging power transmission device 110 to be coupled to the power receiving coil of the wireless charging receiving device 120.

[0072] In the embodiment shown in Figure 1, a magnetic member may be provided near the frame of the wireless charging power transmission device 110. The magnetic member may be configured to attach the wireless charging power receiving device 120 to the frame of the wireless charging power transmission device 110 so that the power transmission coil of the wireless charging power transmission device 110 can be stably coupled to the power receiving coil of the wireless charging power receiving device 120.

[0073] In the embodiment shown in Figure 3, the wireless charging receiving device 120 may be folded and housed in a cavity of the wireless charging transmitting device 110. The wireless power receiving circuit 122 of the wireless charging receiving device 120 may be located near the wireless power receiving circuit 113 of the wireless charging transmitting device 110, so that the transmitting coil of the wireless charging transmitting device 110 can be stably coupled to the receiving coil of the wireless charging receiving device 120.

[0074] The wireless power receiving circuit 113 can transmit a changing magnetic field via a transmitting coil. The coil of the wireless power receiving circuit 122 induces a magnetic field from the wireless power receiving circuit 113 and generates an induced current. The wireless power receiving circuit 122 can transmit the induced current generated by the coil to another component in the wireless charging receiving device 120, such as a battery. In this scenario, the coil of the wireless charging transmitting device 110 may be a transmitting coil, and the coil of the wireless charging receiving device 120 may be a receiving coil.

[0075] In some embodiments, the wireless charging transmitter 110 may alternatively be a wireless charging receiver, in other words, another device may wirelessly charge the wireless power receiving circuit 113. The coils of the wireless power receiving circuit 113 induce a magnetic field from the other device and generate an induced current. The wireless power receiving circuit 113 can transmit the induced current generated by the coils to other components within the wireless power receiving circuit 113. In this scenario, the coils of the wireless charging transmitter 110 may be receiving coils. In other words, the coils of the wireless charging transmitter 110 can function as both transmitting and receiving coils. For example, in the embodiment shown in Figure 3, a glasses case can obtain power from the wireless charging device via the wireless power receiving circuit 113.

[0076] In some other embodiments, the wireless charging receiver 120 may alternatively be a wireless charging transmitter, in other words, the wireless power receiving circuit 122 may wirelessly charge another device. The coil of the wireless power receiving circuit 122 may transmit a changing magnetic field, thereby allowing the wireless charging receiver 120 to wirelessly charge another device. In this scenario, the coil of the wireless charging receiver 120 may be a transmitting coil. In other words, the coil of the wireless charging receiver 120 can function as both a receiving coil and a transmitting coil. For example, in the embodiment shown in Figure 1, a stylus can wirelessly charge another device via the wireless power receiving circuit 122. As another example, in the embodiment shown in Figure 2, smart glasses can wirelessly charge another device via the wireless power receiving circuit 12.

[0077] In some embodiments provided in this application, the coil may be a toroidal winding made by tightly winding a conductor. The conductor may be wrapped in an insulating material.

[0078] Figure 4 is a diagram illustrating the principle of wireless charging. As shown in Figure 4, the wireless charging scenario includes a transmitting end 210 (i.e., a power supply device) and a receiving end 220 (i.e., a power receiving device). Both the transmitting end 210 and the receiving end 220 have wireless charging capabilities to carry out the wireless charging process from the transmitting end 210 to the receiving end 220.

[0079] The transmitting end 210 may include a first coil 211, a first chip 212, and a power supply 213, and the receiving end 220 may include a second coil 221, a second chip 222, and a load 223. The first coil 211 and the second coil 221 are configured to perform energy coupling. The first chip 212 and the second chip 222 are configured to perform wireless charging control or management. The power supply 213 and the load 223 are configured to store electrical energy.

[0080] After the wireless charging area of ​​the transmitting end 210 is aligned with the wireless charging area of ​​the receiving end 220, the transmitting end 210 may wirelessly charge the receiving end 220. Specifically, in the wireless charging process, the transmitting end 210 may control the power supply 213 via the first chip 212 to output current to the first coil 211 (i.e., the power output coil), thereby the first coil 211 may send a high-frequency magnetic field, in other words, convert an electrical signal into a magnetic signal. The high-frequency magnetic field may also pass through the second coil 221 (i.e., the power receiving coil), thereby generating an induced current on the second coil 221, in other words, converting the magnetic signal into an electrical signal. The second chip 222 detects the induced current and inputs it to the load 223.

[0081] In some embodiments, the first chip 212 may include a voltage conversion module and a power transmission circuit. The voltage conversion module is configured to perform voltage conversion, and the power transmission circuit is configured to convert DC to AC electrical signals. Correspondingly, the first coil 211 is configured to convert the AC electrical signals to magnetic signals and transmit the magnetic signals.

[0082] In some embodiments, the second chip 222 may include a voltage conversion module and a power receiving circuit. The second coil 221 is configured to convert a magnetic signal to an AC electrical signal, the power receiving circuit is configured to convert the AC electrical signal to a DC signal, and the voltage conversion module is configured to perform the voltage conversion.

[0083] The power limitations of mobile or portable wireless charging devices such as mobile phones are gradually increasing. Therefore, to improve the user's charging experience and shorten charging time, it is necessary to increase the wireless charging power. However, since the heat dissipation capacity of terminal devices is limited, the efficiency of the wireless charging receiving end needs to be further improved in order to support higher wireless charging power.

[0084] Conventional technology adjusts the output voltage by pulse modulation. However, the modulation frequency of pulse modulation is generated based on the main frequency of wireless charging, and the main frequency needs to be detected. Therefore, continuous voltage adjustment is not supported.

[0085] To solve the aforementioned problems, with reference to Figure 5, one embodiment of the present application provides a wireless power receiving circuit 500 including a power receiving coil 501, a matching circuit 505, a rectifier circuit 504, a controller 503, and an output terminal. The rectifier circuit 504 includes at least one switching unit 502.

[0086] In the wireless power receiving circuit 500, the receiving coil 501 may be connected to the matching circuit 505 in order to form an oscillation circuit on the side of the wireless power receiving circuit 500. The receiving coil 501 receives power transmitted from the transmitting coil through coil coupling and converts it into alternating current by the oscillation circuit. The rectifier circuit 504 is connected to the oscillation circuit and is configured to receive the alternating current output by the oscillation circuit and rectify the alternating current to obtain a direct current.

[0087] The rectifier circuit 504 may include an uncontrolled rectifier circuit 504 or a synchronous rectifier circuit 504. The uncontrolled rectifier circuit 504 includes at least one diode, and the synchronous rectifier circuit 504 includes at least one metal-oxide-semiconductor field-effect transistor (MOSFET). This is not limited to this embodiment of the present application.

[0088] In possible implementations, the rectifier circuit 504 includes at least one switching unit 502. The switching unit may be a controllable switching unit in the rectifier bridge of the rectifier circuit 504, or a switching unit connected in parallel with the diodes in the rectifier bridge.

[0089] 1. The switching unit may be a switching unit connected in parallel with the diodes in the rectifier bridge.

[0090] In a possible implementation, the rectifier circuit 504 includes a rectifier bridge. The rectifier bridge includes multiple diodes, and each switching unit is connected in parallel to one of the diodes. For example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, and the multiple diodes include high-side diodes and low-side diodes, and both the first switching unit 5021 and the second switching unit 5022 are connected in parallel to the low-side diode. In another example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, and the multiple diodes include high-side diodes and low-side diodes, and both the first switching unit 5021 and the second switching unit 5022 are connected in parallel to the high-side diode. In another example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, and the diodes include high-side diodes and low-side diodes, the first switching unit 5021 is connected in parallel to the low-side diodes, the second switching unit 5022 is connected in parallel to the high-side diodes, and the first switching unit 5021 and the second switching unit 5022 are not directly connected. For example, the first switching unit 5021 is connected in parallel to the high-side diode of the left leg, and the first switching unit 5021 is connected in parallel to the low-side diode of the right leg. Alternatively, the first switching unit 5021 is connected in parallel to the high-side diode of the right leg, and the first switching unit 5021 is connected in parallel to the low-side diode of the left leg.

[0091] In a possible implementation, at least one switching unit 502 includes only the first switching unit 5021. For example, the first switching unit 5021 may be connected in parallel to the high-side diode of the left leg, or in parallel to the high-side diode of the right leg, or in parallel to the low-side diode of the left leg, or in parallel to the low-side diode of the right leg.

[0092] 2. The switching unit may be a controllable switching unit within the rectifier bridge of the rectifier circuit 504.

[0093] In a possible implementation, the rectifier circuit 504 further includes a rectifier bridge, which includes a plurality of controllable switching transistors, including at least one switching unit 502. For example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, where both the first and second switching units 5021 and 5022 are high-side controllable switching transistors. In another example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, where both the first and second switching units 5021 and 5022 are low-side controllable switching transistors. In another example, at least one switching unit 502 includes a first switching unit 5021 and a second switching unit 5022, where the first switching unit 5021 is a low-side controllable switching transistor in the left leg and the second switching unit 5022 is a high-side controllable switching transistor in the right leg. Alternatively, the first switching unit 5021 is a high-side controllable switching transistor in the left leg and the first switching unit 5021 is a low-side controllable switching transistor in the right leg.

[0094] In a possible implementation, at least one switching unit 502 includes only the first switching unit 5021. For example, the first switching unit 5021 is a high-side controllable switching transistor with a left leg, or a high-side controllable switching transistor with a right leg, or a low-side controllable switching transistor with a left leg, or a low-side controllable switching transistor with a right leg.

[0095] In a possible implementation, the controller 503 is configured to determine the duty cycle of at least one switching unit 502 based on the output voltage at the voltage output terminal and to control the turn-on or turn-off of at least one switching unit 502 based on the duty cycle (e.g., a modulated signal acquired based on the duty cycle) in order to perform voltage regulation relative to the output voltage, wherein the duty cycle is independent of the main frequency of the radio power receiving circuit 500.

[0096] Since the duty cycle is independent of the main frequency of the wireless power receiving circuit 500, the duty cycle may not be an integer multiple of the main frequency. Therefore, if the output voltage changes continuously, the duty cycle will also change continuously.

[0097] In existing implementations, the main frequency must be detected in order to perform voltage regulation, and the determined duty cycle of the switching transistor is an integer multiple of the main frequency. Therefore, continuous voltage regulation cannot be performed. In this application, voltage regulation operation can be performed without using an additional voltage regulator from the standpoint of hardware structure, and the duty cycle is independent of the main frequency of the wireless power receiving circuit 500, and as a result, continuous voltage regulation can be performed without the need to detect the main frequency.

[0098] If at least one switching unit 502 includes a plurality of switching units (for example, a first switching unit 5021 and a second switching unit 5022 as described in the above embodiments), controlling the turn-on or turn-off of at least one switching unit 502 includes controlling the first switching unit 5021 and the second switching unit 5022 to turn on or turn off simultaneously.

[0099] It should be understood that if at least one switching unit 502 includes only one switching unit (for example, only the first switching unit 5021 described in the above embodiment), the boost adjustment range can reach up to twice the initial value. If at least one switching unit 502 includes multiple switching units (for example, the first switching unit 5021 and the second switching unit 5022 described in the above embodiment), the boost adjustment range can reach an unlimited amount.

[0100] For example, Figure 8 shows an example of a duty cycle in a modulated signal.

[0101] Referring to Figure 6, one embodiment of the present application further provides a wireless power receiving circuit 500 including a power receiving coil 501, a detuning circuit 506, a rectifier circuit 504, a controller 503, and an output terminal. The detuning circuit 506 includes a matching circuit 505 and a grounded target branch, the matching circuit 505 being connected to the target branch, the target branch including a detuning capacitor and a switching unit 508.

[0102] In a possible implementation, the matching capacitor includes a first capacitor and a second capacitor, the first and second capacitors located at the first end of the receiving coil 501; the target branch includes a first branch and a second branch, the first branch includes a first detuning capacitor 5071 and a first switching unit 5081, the second branch includes a second detuning capacitor 5072 and a second switching unit 5082, the first branch is connected between the node between the first and second capacitors and ground, and the second branch is connected between the node at the second end of the receiving coil 501 and ground.

[0103] The controller 503 is configured to determine the duty cycle of the switching unit based on the output voltage at the voltage output terminal and to control the turn-on or turn-off of the switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit 500.

[0104] This is equivalent to the detuning capacitor and switching transistor being directly connected in series between the matching circuit 505 and ground, and the controller 503 generates a modulated signal S2 independent of the main frequency of wireless charging to control the on / off state of the switch and perform step-down control.

[0105] Since the duty cycle is independent of the main frequency of the wireless power receiving circuit 500, the duty cycle may not be an integer multiple of the main frequency. Therefore, if the output voltage changes continuously, the duty cycle will also change continuously.

[0106] The embodiments described above in Figures 5 and 6 may be combined with each other to implement the results of the step-down and step-up functions. Referring to Figure 7, specifically, two groups of switches may be added to the original rectifier circuit 504 and matching circuit 505, and modulated signals S1 and S2, which are independent of the main operating frequency of wireless charging, are used to perform voltage regulation. The first group of switches is each connected in parallel to the two ends of the rectifier diode, and step-up control is performed by controlling the duty cycle d1 of the independent signal S1. The independent signal S1 may alternatively be used on a synchronous rectifier switching transistor to perform step-up control. The second group of switches is each connected in series with a detuning capacitor and grounded, and step-down control is implemented by controlling the duty cycle d2 of the independent signal S2. The switching elements are connected in parallel with the rectifier diode, and the controller 503 generates a modulated signal S1, which is independent of the main frequency of wireless charging, to control the on / off state of the switches and perform step-up control. Alternatively, the modulated signal may be used directly on the synchronous rectifier switching transistor. The detuning capacitor and switching transistor are directly connected in series between the matching circuit 505 and ground, and the controller 503 generates a modulated signal S2 independent of the main frequency of wireless charging to control the on / off state of the switch and achieve step-down control.

[0107] The wireless power receiving circuit provided in the embodiments of this application may be applied to a charging device, a vehicle, or a portable electronic device, and may be used as a receiving or transmitting end for electrical energy.

[0108] Vehicles are used as an example. With the widespread adoption of vehicles, automobiles and similar vehicles have become an indispensable means of transportation in people's daily lives. However, the development cycle of vehicles is long, and updates and iterations are slow, which makes it impossible to meet the diverse and personalized requirements of consumers. Consumer electronics such as mobile phones and watches are convenient for consumers to carry with them. Due to the advantages of the products, namely their short lifecycle and rapid updates and iterations, they can adapt to rapidly changing scenario requirements. Therefore, ecological integration of the consumer electronics industry and the automotive industry is essential. In the embodiments of this application, by applying a wireless power receiving circuit to a vehicle, it is possible to facilitate the practice of incorporating consumer electronics into vehicles.

[0109] In some embodiments, the wireless power receiving circuit according to the embodiment of the present application may be provided in at least one of the vehicle's control console, seat back, door armrest, center armrest, door trim, and trunk, thereby allowing the user to conveniently charge in-vehicle eco-devices via the wireless power receiving circuit. In embodiments of the present application, when the wireless power receiving circuit is installed in a vehicle, the wireless power receiving circuit may be electrically connected to the vehicle's power supply circuit, and the energy source for the wireless power receiving circuit is the vehicle. That is, the wireless power receiving circuit can obtain energy from the vehicle's power supply circuit and wirelessly charge other devices.

[0110] In some embodiments, the wireless power receiving circuit according to the embodiment of the present application may be installed in the vehicle as a pre-installed component. That is, the wireless power receiving circuit is incorporated into the vehicle as a pre-installed component before the vehicle leaves the factory. In this way, the vehicle can charge onboard eco-devices without using exposed wires or charging interfaces, thereby improving aesthetics and helping to meet the diverse and personalized scenario requirements of users.

[0111] In some other embodiments, the wireless power receiving circuit provided in the embodiments of this application is installed in a vehicle by using a removable connection structure. For example, the wireless power receiving circuit is installed in a vehicle by using clamp jaws, buckles, threads, adhesive closure strips, etc. In this way, it may be convenient for the user to charge the on-board eco-device by using the wireless power receiving circuit at different locations in the vehicle. In some embodiments, the wireless power receiving circuit may be electrically connected to a charging interface on the vehicle via a charging connector, or it may be electrically connected to a charging interface via contacts.

[0112] The foregoing description is merely a specific implementation of the present application and is not intended to limit the scope of protection of the present application. Any modifications or substitutions that are readily conceivable by a person skilled in the art within the scope of the art disclosed herein shall fall within the scope of protection of the present application. Accordingly, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. A wireless power receiving circuit comprising a power receiving coil, a matching circuit, a rectifier circuit, a controller, and an output terminal, wherein the rectifier circuit includes at least one switching unit, The receiving coil is configured to receive energy and output alternating current. The matching circuit is configured to perform matching with the AC current and to transmit the AC current to the input terminal of the rectifier circuit. The rectifier circuit is configured to convert the input AC current into a DC current. The controller is configured to determine the duty cycle of the at least one switching unit based on the output voltage of the voltage output terminal, and to control the turn-on or turn-off of the at least one switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit.

2. The wireless power receiving circuit according to claim 1, wherein the duty cycle is not an integer multiple of the main frequency.

3. The wireless power receiving circuit according to claim 1 or 2, wherein when the output voltage changes continuously, the duty cycle changes simultaneously and continuously.

4. The wireless power receiving circuit according to any one of claims 1 to 3, wherein the rectifier circuit further includes a rectifier bridge, the rectifier bridge includes a plurality of diodes, and each switching unit is connected in parallel to one of the diodes.

5. The wireless power receiving circuit according to claim 4, wherein the at least one switching unit includes only the first switching unit.

6. The at least one switching unit includes a first switching unit and a second switching unit, and the plurality of diodes includes high-side diodes and low-side diodes. Both the first switching unit and the second switching unit are connected in parallel to the low-side diode, or Both the first switching unit and the second switching unit are connected in parallel to the high-side diode, or The wireless power receiving circuit according to claim 4, wherein the first switching unit is connected in parallel to the low-side diode, the second switching unit is connected in parallel to the high-side diode, and the first switching unit and the second switching unit are not directly connected.

7. The wireless power receiving circuit according to claim 6, wherein controlling the turn-on or turn-off of at least one switching unit includes controlling the first switching unit and the second switching unit to turn on or turn off simultaneously.

8. The wireless power receiving circuit according to any one of claims 1 to 3, wherein the rectifier circuit further includes a rectifier bridge, the rectifier bridge includes a plurality of controllable switching transistors, each including at least one switching unit.

9. The wireless power receiving circuit according to claim 8, wherein the at least one switching unit includes only the first switching unit.

10. The at least one switching unit includes a first switching unit and a second switching unit. Both the first switching unit and the second switching unit are low-side controllable switching transistors, or Both the first switching unit and the second switching unit are high-side controllable switching transistors, or The wireless power receiving circuit according to claim 8 or 9, wherein the first switching unit is a low-side controllable switching transistor, the second switching unit is a high-side controllable switching transistor, and the first switching unit and the second switching unit are not directly connected.

11. The wireless power receiving circuit according to claim 10, wherein controlling the turn-on or turn-off of at least one switching unit includes controlling the first switching unit and the second switching unit to turn on or turn off simultaneously.

12. A wireless power receiving circuit comprising a power receiving coil, a detuning circuit, a rectifier circuit, a controller, and an output terminal, wherein the detuning circuit comprises a matching circuit and a grounded target branch, the matching circuit is connected to the target branch, and the target branch comprises a detuning capacitor and a switching unit, The receiving coil is configured to receive energy and output alternating current. The rectifier circuit is configured to convert the input AC current into a DC current. The controller is configured to determine the duty cycle of the switching unit based on the output voltage of the voltage output terminal, and to control the turn-on or turn-off of the switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit.

13. The wireless power receiving circuit according to claim 12, wherein the duty cycle is not an integer multiple of the main frequency.

14. The wireless power receiving circuit according to claim 12 or 13, wherein when the output voltage changes continuously, the duty cycle changes simultaneously and continuously.

15. A wireless power receiving circuit according to any one of claims 12 to 14, wherein the matching capacitor includes a first capacitor and a second capacitor, the first capacitor and the second capacitor located at the first end of the power receiving coil, the target branch includes a first branch and a second branch, the first branch includes a first detuning capacitor and a first switching unit, the second branch includes a second detuning capacitor and a second switching unit, the first branch is connected between the node between the first capacitor and the second capacitor and ground, and the second branch is connected between the node at the second end of the power receiving coil and ground.

16. The wireless power receiving circuit according to claim 15, wherein controlling the switching unit to turn on or off includes controlling the first switching unit and the second switching unit to turn on or off simultaneously.

17. A wireless charging device comprising a wireless power receiving circuit and an energy storage device according to any one of claims 1 to 16, The wireless power receiving circuit is configured to receive electrical energy and transmit the electrical energy to the energy storage device, and is a wireless charging device.

18. A charging system comprising a wireless charging device and a wireless charging device as described in claim 17, A charging system comprising a power transmission coil included in the wireless charging device, configured to transmit energy to the wireless charging device.

19. A wireless charging control method applied to the receiving end of wireless charging, wherein the receiving end includes a receiving coil, a matching circuit, a rectifier circuit, a controller, and an output end, and the rectifier circuit includes at least one switching unit. A wireless charging control method comprising determining the duty cycle of the at least one switching unit based on the output voltage of the voltage output terminal, and controlling the turn-on or turn-off of the at least one switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit.

20. The method according to claim 19, wherein the duty cycle is not an integer multiple of the main frequency.

21. The method according to claim 19 or 20, wherein when the output voltage changes continuously, the duty cycle changes simultaneously and continuously.

22. A wireless charging control method applied to the receiving end of wireless charging, wherein the receiving end includes a receiving coil, a detuning circuit, a rectifier circuit, a controller, and an output terminal, the detuning circuit includes a matching circuit and a grounded target branch, the matching circuit is connected to the target branch, and the target branch includes a detuning capacitor and a switching unit, A wireless charging control method comprising determining the duty cycle of the switching unit based on the output voltage of the voltage output terminal, and controlling the turn-on or turn-off of the switching unit based on the duty cycle in order to perform voltage adjustment with respect to the output voltage, wherein the duty cycle is independent of the main frequency of the wireless power receiving circuit.

23. The method according to claim 22, wherein the duty cycle is not an integer multiple of the main frequency.

24. The method according to claim 22 or 23, wherein when the output voltage changes continuously, the duty cycle changes simultaneously and continuously.

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