Charging device for vehicle, charging method for vehicle, and storage medium

Abstract

This application provides a charging device for a vehicle, a charging method for a vehicle, and a computer-readable storage medium. The charging device includes an AC-AC converter and a control device. The AC-AC converter performs low-frequency to high-frequency conversion of AC power. The control device is configured to control the AC-AC converter to convert the initial AC power to a target AC power, and then charge the vehicle using the target AC power. Thus, this application enables the charging device to directly convert low-frequency AC power to high-frequency AC power through a single-stage power conversion. Therefore, the charging device and the vehicle only need to complete two stages of power conversion together to achieve wireless charging of the vehicle. Compared to traditional charging schemes that require three stages of power conversion, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the need for the power factor correction converter input inductor and the large-capacity bus electrolytic capacitor found in traditional schemes.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a charging device for a vehicle, a charging method for a vehicle, and a computer-readable storage medium. Background Technology

[0002] In traditional single-phase wireless charging systems, the system can often be divided into three components: the wall-end, the ground-end, and the vehicle-end. The wall-end component includes two stages of converters: a power factor correction (PFC) converter to convert AC power to DC power; and a high-frequency direct current to alternating current (DCAC) converter to convert DC power to high-frequency AC power to excite the transmitting coil. The vehicle-end component includes a high-frequency alternating current to direct current (ACCDC) converter to convert the AC power induced by the receiving coil into DC power to charge the battery.

[0003] However, this three-stage converter topology includes many components such as PFC input inductors and output bus electrolytic capacitors, resulting in higher overall system cost and larger size. At the same time, the charging efficiency is lower due to the large losses introduced by the multi-stage conversion, and the system control and debugging complexity is also higher. Summary of the Invention

[0004] This application provides a charging device for a vehicle, a charging method for a vehicle, and a computer-readable storage medium.

[0005] This application provides a charging device for a vehicle, which includes an AC-AC converter and a control device. The AC-AC converter is used to convert AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and to charge the vehicle through the target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

[0006] Thus, in this embodiment, the charging device for a vehicle may include a control device and an AC-AC converter for converting AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and then charge the vehicle using the target AC power. This allows the charging device to directly convert low-frequency AC power to high-frequency AC power through a single-stage power conversion. Therefore, the charging device and the vehicle only need to complete two stages of power conversion to wirelessly charge the vehicle. Compared to traditional charging schemes that require three stages of power conversion, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the input inductor of the power factor correction converter and the large-capacity bus electrolytic capacitor found in traditional schemes, reducing the device size and minimizing power losses caused by multi-stage conversion. This ensures both miniaturization and low cost of the charging device while improving power conversion efficiency and charging stability.

[0007] In some embodiments provided in this application, the AC-AC converter includes a matrix converter and a compensation network. The matrix converter is electrically connected to the compensation network. The matrix converter includes a first upper bridge arm, a first lower bridge arm, a second upper bridge arm, and a second lower bridge arm. Each bridge arm consists of two anti-tandem switching devices. The first end of the first upper bridge arm and the first end of the second upper bridge arm are both electrically connected to one end of the first common node. The other end of the first common node is electrically connected to the first input terminal of the compensation network. The second end of the first upper bridge arm is electrically connected to the first end of the first lower bridge arm to form the first input terminal of the matrix converter. The second end of the second upper bridge arm is electrically connected to the first end of the second lower bridge arm to form the second input terminal of the matrix converter. The second end of the first lower bridge arm and the second end of the second lower bridge arm are both electrically connected to one end of the second common node. The other end of the second common node is electrically connected to the second input terminal of the compensation network.

[0008] Thus, in this embodiment of the application, the AC-AC converter of the charging device can be implemented through a matrix converter and a compensation network, thereby completing the direct conversion from power frequency AC to high frequency AC.

[0009] In some embodiments provided in this application, the AC-AC converter includes a rectifier bridge, a switching circuit, and a compensation network, wherein the switching circuit includes a first switching device, a second switching device, a third switching device, and a fourth switching device; The first output terminal of the rectifier bridge is electrically connected to one end of the third common node, and the other end of the third common node is electrically connected to the first end of the first switching device and the first end of the third switching device. The second output terminal of the rectifier bridge is electrically connected to one end of the fourth common node, and the other end of the fourth common node is electrically connected to the first end of the second switching device and the first end of the fourth switching device. The second end of the first switching device is electrically connected to the first end of the second switching device to form the third output terminal of the switching circuit. The second end of the third switching device is electrically connected to the first end of the fourth switching device to form the fourth output terminal of the switching circuit. The third output terminal and the fourth output terminal of the switching circuit are electrically connected to the compensation network.

[0010] Thus, in this embodiment, the AC-AC converter can be implemented through a rectifier bridge, a switching circuit, and a compensation network, thereby changing the charging device's low-frequency to high-frequency AC conversion from a traditional two-stage conversion to a single-stage conversion, thus improving the power conversion efficiency of the charging device.

[0011] In some embodiments provided in this application, the AC-AC converter further includes a filter capacitor, and the rectifier bridge is electrically connected to the switching circuit through the filter capacitor.

[0012] Thus, in this embodiment, a filter capacitor can be added between the rectifier bridge and the switching circuit of the AC-AC converter, thereby eliminating high-frequency harmonic interference, improving the working accuracy of the switching circuit and the resonance stability of the compensation network, thereby ensuring the conversion efficiency and operational reliability of vehicle wireless charging, and improving the overall performance of the charging equipment.

[0013] In some embodiments provided in this application, the charging device further includes a filter circuit, the power supply device is electrically connected to the filter circuit, the filter circuit is electrically connected to the AC-AC converter, and the filter circuit receives electrical energy input from the power supply device and outputs the initial AC power to the AC-AC converter.

[0014] Thus, in this embodiment of the application, a filter circuit can be added between the power supply device and the AC-AC converter, so that the AC-AC converter can receive stable and pure initial AC power through the filter circuit.

[0015] This application provides a charging control method for a vehicle, wherein the vehicle is electrically connected to the charging device according to any one of claims 1-6, the method comprising: The AC-AC converter is controlled to perform the conversion process on the initial AC power to obtain the target AC power. The vehicle is charged using the target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

[0016] Thus, in this embodiment, the charging device for a vehicle may include a control device and an AC-AC converter for converting AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and then charge the vehicle using the target AC power. This allows the charging device to directly convert low-frequency AC power to high-frequency AC power through a single-stage power conversion. Therefore, the charging device and the vehicle only need to complete two stages of power conversion to wirelessly charge the vehicle. Compared to traditional charging schemes that require three stages of power conversion, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the input inductor of the power factor correction converter and the large-capacity bus electrolytic capacitor found in traditional schemes, reducing the device size and minimizing power losses caused by multi-stage conversion. This ensures both miniaturization and low cost of the charging device while improving power conversion efficiency and charging stability.

[0017] In some embodiments provided in this application, controlling the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power includes: Obtain the current reference current and the current input voltage and current input current of the power supply device; The current phase of the power supply device is determined based on the current input voltage; Based on the current reference current, the current phase, and the current input current, the charging device is controlled so that the AC-AC converter performs the conversion process on the initial AC power and outputs the target AC power.

[0018] Thus, in this embodiment, the current reference current and the current input voltage and current of the power supply device can be obtained, and the current phase of the power supply device can be determined based on the current input voltage. Based on the current reference current, the current phase, and the current input current, the charging device can be controlled so that the AC-AC converter performs the conversion process on the initial AC power and outputs the target AC power. This enables phase synchronization between the charging device and the power supply device, real-time correction of conversion deviation through current closed-loop feedback, improvement of the power factor of the input current, reduction of power conversion loss, and simultaneous assurance of stable and reliable output target AC power.

[0019] In some embodiments provided in this application, controlling the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power includes: The target alternating current is used to generate the current output voltage and current output current; Based on the current output voltage and current, as well as the obtained reference electrical parameters, the vehicle is controlled to cooperate with the charging equipment for charging.

[0020] Thus, in this embodiment, the target AC power can be used to generate the current output voltage and current output current. Based on the current output voltage and current output current, as well as the obtained reference electrical parameters, the vehicle can be controlled to enable the vehicle to cooperate with the charging device for charging. This allows for vehicle-to-vehicle coordinated control by collecting the actual output electrical parameters of the vehicle and combining them with the reference electrical parameters, thereby ensuring the stability and accuracy of the charging voltage and current, matching the charging electrical parameters to the charging requirements of the vehicle's power battery, avoiding safety hazards such as overvoltage and overcurrent, and improving the safety and reliability of wireless charging.

[0021] In some embodiments provided in this application, the AC-AC converter includes a matrix converter and a compensation network, the matrix converter is electrically connected to the compensation network, and the matrix converter includes multiple bridge arms, each bridge arm consisting of two anti-connected fifth and sixth switching devices. The charging control method further includes: When the initial AC current is in the positive half-cycle, the sixth switching device of each bridge arm in the matrix converter is controlled to be in the conducting state, so as to realize AC-AC conversion through the fifth switching device of each bridge arm in the matrix converter. When the initial AC current is in the negative half-cycle, the fifth switching device of each bridge arm in the matrix converter is controlled to be in the on state, so as to realize AC-AC conversion through the sixth switching device of each bridge arm in the matrix converter.

[0022] Thus, in the embodiments of this application, during the charging control process, the sixth and fifth switching devices of each bridge arm of the matrix converter can be controlled to conduct according to the positive and negative half-cycle states of the initial AC power, thereby reducing the number of high-frequency switching of the matrix converter switching devices, reducing switching losses and device heat generation, simplifying the drive control logic, improving the overall efficiency of the wireless charging system, reducing the hardware cost of the charging equipment, and reducing the size of the equipment.

[0023] This application provides a computer-readable storage medium storing a computer program that, when executed by one or more processors, implements the above-described charging method for a vehicle.

[0024] This application provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the above-described charging method for a vehicle.

[0025] Thus, in this embodiment, the charging device for a vehicle may include a control device and an AC-AC converter for converting AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and then charge the vehicle using the target AC power. This allows the charging device to directly convert low-frequency AC power to high-frequency AC power through a single-stage power conversion. Therefore, the charging device and the vehicle only need to complete two stages of power conversion to wirelessly charge the vehicle. Compared to traditional charging schemes that require three stages of power conversion, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the input inductor of the power factor correction converter and the large-capacity bus electrolytic capacitor found in traditional schemes, reducing the device size and minimizing power losses caused by multi-stage conversion. This ensures both miniaturization and low cost of the charging device while improving power conversion efficiency and charging stability.

[0026] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein: Figure 1 One of the schematic diagrams of a charging device provided in certain embodiments of this application; Figure 2 A second schematic diagram of a charging device provided for certain embodiments of this application; Figure 3 One of the schematic diagrams of a charging system provided for certain embodiments of this application; Figure 4 A second schematic diagram of a charging system provided for certain embodiments of this application; Figure 5a One of the topology diagrams of the compensation network provided in the embodiments of this application; Figure 5b A second schematic diagram of the topology of the compensation network provided for an embodiment of this application; Figure 5c The third schematic diagram of the topology of the compensation network provided for the implementation of this application; Figure 6aOne of the topology diagrams of the secondary-side AC-DC switching network provided for an embodiment of this application; Figure 6b A second schematic diagram of the topology of the secondary-side AC-DC switching network provided for the implementation of this application; Figure 6c The third schematic diagram of the topology of the secondary-side AC-DC switching network provided for the implementation of this application; Figure 7 Schematic diagram three of the charging systems provided for certain embodiments of this application; Figure 8 Fourth schematic diagram of a charging system provided for certain embodiments of this application; Figure 9 Fifth schematic diagram of a charging system provided for certain embodiments of this application; Figure 10 A schematic flowchart illustrating a charging control method provided in certain embodiments of this application; Figure 11 A schematic diagram of a charging control device provided for certain embodiments of this application; Figure 12 A schematic diagram of the charging device-side control logic provided for certain embodiments of this application; Figure 13 One of the timing diagrams of the driving signals for the switching devices on the charging device side provided in certain embodiments of this application; Figure 14 A second timing diagram of the driving signals for the switching devices on the charging device side provided in certain embodiments of this application; Figure 15 A schematic diagram of vehicle-side control logic provided for certain embodiments of this application; Figure 16 A timing diagram of the drive signals for the vehicle-side switching device provided in certain embodiments of this application; Figure 17a A timing diagram of the switching device drive signal during the positive half-cycle of the voltage provided in certain embodiments of this application; Figure 17b This is a timing diagram of the switching device drive signal during the negative half-cycle of the voltage provided in certain embodiments of this application. Detailed Implementation

[0028] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of this application, and should not be construed as limiting the embodiments of this application.

[0029] In related technologies, single-phase wireless charging systems are typically divided into three main components: vehicle-side components, ground-side components, and wall-side components. The overall structure can be assembled as follows: Figure 1 As shown. The wall-mounted components typically integrate two stages of power conversion circuitry. The first stage is an Alternating Current-Direct Current (ACCDC) converter, often called a Power Factor Correction (PFC) converter, responsible for converting the single-phase power grid's AC frequency into DC power. The second stage is a high-frequency Direct Current-Alternating Current (DCAC) converter, responsible for converting the DC power into high-frequency AC power suitable for coil energy transfer, serving as the excitation signal for coil energy transfer. The high-frequency DCAC converter usually comprises two parts: a DC-AC switching network and a compensating resonant network.

[0030] The grounding component uses a transmitting coil as its core component and can also integrate foreign object detection and liveness detection devices. The transmitting coil is connected to a high-frequency DC-AC converter in the wall-mounted component. The high-frequency AC power output from the high-frequency DC-AC converter is transmitted to the transmitting coil inside the grounding component, which can excite the transmitting coil to generate a high-frequency alternating magnetic field.

[0031] The vehicle-side components mainly include a receiving coil and a high-frequency alternating current-to-direct current (AC-DC) converter. The AC-DC converter in the vehicle-side components also consists of an AC-DC switching network and a compensated resonant network. The receiving coil, situated in the high-frequency alternating magnetic field generated by the transmitting coil, induces a corresponding high-frequency alternating potential. This high-frequency alternating potential is converted into direct current by the high-frequency AC-DC converter and stably output to the vehicle's power battery to provide charging power.

[0032] Based on the structure and working principle of the aforementioned components, the entire single-phase wireless charging system comprises three power converters: a power factor correction converter, a high-frequency DC-AC converter, and a high-frequency AC-DC converter. The power factor correction converter and the high-frequency DC-AC converter are located inside the wall-mounted components, while the high-frequency AC-DC converter is located in the vehicle-mounted components. This three-stage topology scheme utilizes a large number of electronic components, especially the input inductor and output bus electrolytic capacitor in the power factor correction converter. This results in higher hardware costs and a larger overall size, and also generates significant power loss during energy transmission, leading to lower overall system efficiency.

[0033] Based on the issues mentioned above, please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of a charging device 100 provided in some embodiments of this application. Figure 3 This is a schematic diagram of a charging system provided in certain embodiments of this application. Embodiments of this application provide a charging device 100 for a vehicle 200. The charging device 100 includes an AC-AC converter 111 and a control device 130. The AC-AC converter 111 is used to convert AC power from low frequency to high frequency. The control device 130 is configured to control the AC-AC converter 111 to convert initial AC power to a target AC power, and to charge the vehicle 200 using the target AC power. The initial AC power is provided by a power supply device 300 electrically connected to the charging device 100.

[0034] Specifically, in related technologies, single-phase wireless charging systems generally adopt a three-stage converter topology, which requires sequential power conversion through a wall-mounted PFC converter, a wall-mounted high-frequency DC-AC converter, and a vehicle-mounted high-frequency AC-DC converter. This topology involves a large number of components and requires the configuration of PFC input inductors and large-capacity bus electrolytic capacitors, resulting in high equipment production costs, large overall size, and additional losses and low power conversion efficiency due to multi-stage power conversion.

[0035] Based on this, this application provides a charging device 100 for a vehicle 200. The charging device 100 integrates an AC-AC converter 111 and a control device 130 to transform the complex three-stage power conversion process in related technologies into a simplified process where the control device 130 regulates the AC-AC converter 111, performs a single-stage conversion of low-frequency AC to high-frequency AC, and uses the target AC to charge the vehicle 200. That is, in this application embodiment, the charging device 100 can regulate the AC-AC converter 111 through the control device 130 to directly convert the low-frequency initial AC input from the power supply device 300 into a high-frequency target AC suitable for charging the vehicle 200, without going through multiple stages of DC intermediate conversion. Thus, the charging process for the vehicle 200 is simplified through a single-stage conversion structure, which can reduce equipment costs and size while ensuring charging efficiency.

[0036] In some implementations, the charging device 100 can be understood as a hardware device designed specifically for the wireless charging scenario of the vehicle 200, integrating power conversion and intelligent control functions, and is the core device for realizing contactless wireless charging of the vehicle 200.

[0037] In some examples, the charging device 100 includes a single-phase wireless charging host device adapted for passenger cars and commercial vehicles.

[0038] In some implementations, the AC-AC converter 111 can be understood as the main power conversion hardware of the charging device 100, which can directly complete the single-stage conversion of AC power from low frequency to high frequency.

[0039] In some examples, the AC-AC converter 111 can be an integrated conversion structure consisting of a single-phase matrix converter or a rectifier bridge with switching circuitry, without the need for additional PFC power inductors and large-capacity bus electrolytic capacitors.

[0040] In some embodiments, the control device 130 can be understood as the control unit of the charging device 100, which has functions such as electrical signal acquisition, phase locking, logic operation, and control command output, and can regulate the working state of the AC-AC converter 111.

[0041] In some examples, the control device 130 can acquire the voltage and current signals of the power supply device 300, and output a pulse width modulation (PWM) drive signal after phase-locked loop and closed-loop operation, thereby realizing the control of the AC conversion process.

[0042] In some implementations, the initial AC power can be understood as the original power frequency AC power input from the external power supply device 300 to the charging device 100, which is the basic input energy for the charging device 100 to perform power conversion.

[0043] In some examples, the initial AC power is single-phase, 220V, 50Hz residential AC power grid energy.

[0044] In some implementations, the target AC power can be understood as high-frequency AC power output after being converted and processed by AC-AC converter 111, with frequency and voltage parameters matching the magnetic field excitation requirements of vehicle 200 wireless charging, and is suitable for vehicle 200 charging scenarios.

[0045] In some examples, the target AC current is a high-frequency AC current with a frequency of 85kHz, adapted to the magnetic field coupling of wireless charging.

[0046] In some implementations, the power supply device 300 can be understood as an external power device that provides raw input electrical energy to the charging device 100, and is the power source of the charging system.

[0047] In some examples, the power supply device 300 is a single-phase power frequency AC grid, vehicle power supply, or other power equipment that can output power frequency AC.

[0048] To more clearly illustrate the working logic of the charging device 100 in the embodiments of this application, please refer to... Figure 3 And the following exemplary description, namely: The charging device 100 first establishes an electrical connection with the power supply device 300 to obtain the initial power frequency AC power output by the power supply device 300, i.e., the initial AC power.

[0049] Then, the control device 130 collects the output voltage and output current signals of the initial AC power, determines the current phase information of the power supply device 300 through the phase-locked loop unit, and completes closed-loop logic operation in combination with preset reference electrical parameters to generate corresponding control commands.

[0050] Next, the control device 130 transmits control commands to the AC-AC converter 111, driving the internal switching devices of the converter to perform a single-stage conversion process of the initial AC power from low frequency to high frequency, generating a target AC power that meets the vehicle 200 charging standard.

[0051] Finally, the charging device 100 transmits the converted target AC power to the transmitting coil 141, and provides stable charging power to the power battery of the vehicle 200 through wireless transmission via magnetic field coupling, thus completing the charging process of the vehicle 200.

[0052] To more clearly illustrate the charging process implemented by the charging device 100 in the embodiments of this application, please refer to [link to relevant documentation]. Figure 3 And the following exemplary description, namely: In such Figure 3 In some examples of the charging systems shown, the power supply unit 300 is a single-phase power grid, and the charging system includes wall-end components, ground-end components, and vehicle-end components. The wall-end components consist of a filter circuit 112 and an AC-AC converter 111. The ground-end components include at least a transmitting coil 141, and the vehicle-end components include a receiving coil, an AC-DC converter, and an on-board high-voltage battery. The AC-DC converter in the vehicle-end components consists of a compensation network and a switching network.

[0053] The single-phase AC power output from the grid first enters the filter circuit 112, where the filter network removes high-order harmonics, spike interference, and electromagnetic noise from the current, resulting in a smooth-waveform AC power output with low interference. Simultaneously, the filter circuit 112 prevents high-frequency harmonics generated during the operation of the AC-AC converter 111 from flowing back into the grid, thus avoiding pollution of the power grid.

[0054] AC-AC converter 111 receives filtered power frequency AC power, and control device 130 (not in) Figure 3 Driven by the power source (as shown in the figure), the power frequency AC power is directly converted into the high frequency AC power required for wireless charging through high frequency chopping and waveform reconstruction, which is also the high frequency excitation current required by the transmitting coil 141.

[0055] The high-frequency AC power obtained by the AC-AC converter 111 is input to the transmitting coil 141. The coil generates a high-frequency alternating magnetic field under the excitation of the high-frequency current, and transmits electrical energy in the form of magnetic field energy, realizing wireless power transmission from the ground end to the vehicle end.

[0056] The receiving coil and transmitting coil 141 in the vehicle-end component are coupled by magnetic field to convert the high-frequency alternating magnetic field transmitted from the ground into high-frequency alternating current, thus completing the wireless reception of electrical energy.

[0057] The high-frequency AC output from the receiving coil enters the compensation network in the AC-DC converter of the vehicle-end components. The compensation network makes the receiving circuit work in a resonant state through resonance, which cancels the inductive reactance of the receiving coil, reduces reactive power loss, and improves the power receiving efficiency.

[0058] The compensated high-frequency AC power enters the switching network of the AC-DC converter in the vehicle-end components. The switching network converts the AC power into DC power through a high-frequency rectifier bridge (or synchronous rectifier circuit). By controlling the on and off of the control switch, the output voltage / current is adjusted so that the adjusted output voltage / current can match the charging specifications of the vehicle's high-voltage battery.

[0059] Finally, the on-board high-voltage battery receives the DC power output from the AC-DC converter in the vehicle-side components, and works with the vehicle's battery management system to complete the charging process, converting electrical energy into chemical energy for storage, and providing power for the vehicle's operation.

[0060] Thus, in this embodiment, the charging device 100 for the vehicle 200 may include a control device 130 and an AC-AC converter 111 for converting AC power from low frequency to high frequency. The control device 130 is configured to control the AC-AC converter 111 to convert the initial AC power to a target AC power, and then charge the vehicle 200 using the target AC power. This allows the charging device 100 to wirelessly charge the vehicle 200 with only two conversion stages. Compared to a three-stage converter charging device 100, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the input inductor of the power factor correction converter and the large-capacity bus electrolytic capacitor found in traditional solutions, reducing the device size and minimizing power loss caused by multiple conversion stages. This ensures the miniaturization and low cost of the charging device 100 while improving power conversion efficiency and charging stability.

[0061] In some embodiments provided in this application, the AC-AC converter 111 includes a matrix converter and a compensation network. The matrix converter includes a first upper arm, a first lower arm, a second upper arm, and a second lower arm, each arm consisting of two anti-parallel connected switching devices. The first end of the first upper arm and the first end of the second upper arm are both electrically connected to one end of a first common node. The other end of the first common node is electrically connected to the first input terminal of the compensation network. The second end of the first upper arm is electrically connected to the first end of the first lower arm to form the first input terminal of the matrix converter. The second end of the second upper arm and the first end of the second lower arm are electrically connected to form the second input terminal of the matrix converter. The second ends of the first lower arm and the second lower arm are both electrically connected to one end of a second common node. The other end of the second common node is electrically connected to the second input terminal of the compensation network.

[0062] Specifically, in some embodiments provided in this application, the AC-AC converter 111 can be implemented by combining a matrix converter and a compensation network. Specifically, the AC-AC converter 111 can use a matrix converter consisting of four bridge arms as the main conversion unit, with each bridge arm equipped with two anti-connected series switching devices. The matrix converter is then connected to the compensation network, thereby constructing a single-stage AC-AC conversion structure without intermediate DC links, directly completing the conversion of power frequency AC to high frequency AC, thus avoiding the defects of two-stage conversion in wall-end components in related technologies.

[0063] In some implementations, a matrix converter can be understood as a conversion unit in the charging device 100 that directly converts power frequency AC power into high frequency AC power.

[0064] In some examples, the matrix converter is composed of semiconductor switching devices and conductive lines, which have bidirectional power transmission and fast switching control capabilities, and can be adapted to the electrical characteristics of a single-phase AC power grid.

[0065] In some implementations, the compensation network can be understood as a resonant compensation unit that works in conjunction with a matrix converter to achieve impedance matching and energy transfer optimization.

[0066] In some implementations, the compensation network is composed of passive devices such as inductors and capacitors, and can be in series, parallel, inductor-capacitor-inductor (LCC), inductor-capacitor-capacitor (LCL) and other topologies.

[0067] In some implementations, the first upper bridge arm, the first lower bridge arm, the second upper bridge arm, and the second lower bridge arm can be understood as four independent switching branches inside the matrix converter, which are paired up to form two sets of full-bridge structures, enabling the switching and conversion of electrical energy.

[0068] In some implementations, a switching device can be understood as an active power electronic component that controls the on / off state of a circuit.

[0069] In some examples, the switching devices can be insulated gate bipolar transistors (IGBTs), silicon metal-oxide-semiconductor field-effect transistors (Si MOSFETs), silicon carbide metal-oxide-semiconductor field-effect transistors (SiCMOSFETs), gallium nitride high electron mobility transistors (GaN HEMTs), etc., which have the characteristics of fast switching speed, low loss and high voltage withstand capability.

[0070] In some implementations, reverse series connection can be understood as two switching devices being connected in series in a manner of anode to anode and cathode to cathode, which can achieve bidirectional voltage blocking and bidirectional current conduction.

[0071] In some implementations, the first common node can be understood as the junction point of the two upper arms of the matrix converter, serving as the positive terminal of the high-frequency AC output of the matrix converter.

[0072] In some implementations, the second common node can be understood as the bus connection point of the two lower arms of the matrix converter, which serves as both the AC input bus and the negative terminal of the high-frequency AC output of the matrix converter.

[0073] In some implementations, the first input terminal and the second input terminal of the matrix converter can be understood as two electrical access ports for the matrix converter to receive the initial AC power input from the power supply device 300.

[0074] In some implementations, the first input terminal and the second input terminal of the compensation network can be understood as two electrical access ports for the compensation network to receive the high-frequency AC power output from the matrix converter, and are connected one-to-one with the output terminal of the matrix converter.

[0075] To more clearly illustrate the hardware composition and working principle of the matrix converter within the AC-AC converter 111 in the embodiments of this application, please refer to [link to relevant documentation]. Figure 4 , Figure 4 This is a schematic diagram of a charging system provided for certain embodiments of this application. Also, please... Figure 4 Based on the above, please refer to the following exemplary description: like Figure 4 As shown, the internal matrix converter of the AC-AC converter 111 includes four bridge arms, namely... S p1g , S p1h The first upper bridge arm, composed of these two switching devices, is made of S p2g , S p2h The first lower bridge arm, composed of these two switching devices, is... S p3g , S p3h The second upper bridge arm, composed of these two switching devices, is... S p4g , S p4h These two switching devices form the second lower bridge arm. In each bridge arm, the two switching devices are connected in reverse series, as in the first upper bridge arm. S p1g , S p1h Reverse series connection. Additionally, the upper end of the first upper bridge arm... S p1g The collector (i.e., the first end of the first upper arm) and the upper end of the second upper arm S p3g The collectors (i.e., the first end of the second upper bridge arm) are connected to the upper busbar node D (i.e., the first common node), and the lower end of the first lower bridge arm... S p2h The collector (i.e., the second end of the first lower bridge arm) and the lower end of the second lower bridge arm S p4h The collectors (i.e., the second end of the second lower bridge arm) are connected to the lower bus node E (i.e., the second common node). The primary-side compensation network is electrically connected to the upper bus node D and the lower bus node E.

[0076] And, the lower end of the first upper bridge arm S p1h The collector (i.e., the second end of the first upper bridge arm) and the upper end of the first lower bridge arm S p2g The collectors (i.e., the first end of the first lower bridge arm) are connected to the midpoint A of the left bridge arm, and the first input of the matrix converter is led out from the midpoint A of the left bridge arm. The lower end of the second upper bridge arm... Sp3h The collector (i.e., the second end of the second upper bridge arm) and the upper end of the second lower bridge arm S p4g The collector (i.e. the first end of the second lower bridge arm) is connected to the midpoint N of the right bridge arm, and the second input of the matrix converter is led out from the midpoint N of the right bridge arm.

[0077] Furthermore, based on such Figure 4 The matrix converter shown, the power supply unit 300 outputs the initial AC power at the industrial frequency. u g Firstly, it goes through the process of... L g and C g An LC filter network is formed. Among them, L g It is a series filter inductor used to suppress high-order harmonics of the input current and improve the power factor on the input side. C g It is a parallel filter capacitor used to absorb voltage spikes on the mains side and smooth the input current waveform.

[0078] The filtered AC power is fed into the two input terminals of the matrix converter, namely the first and second input terminals mentioned above, to provide a stable input for the subsequent power conversion that the matrix converter will perform.

[0079] The control device 130 controls each switching device in the matrix converter (i.e., S p1g , S p1h , S p2g , S p2h , S p3g , S p3h , S p4g , S p4h The switching on and off of the matrix converter allows it to convert the received power frequency AC power into high frequency AC power, i.e., into high frequency AC voltage. U p , and output.

[0080] High-frequency AC voltage output by the matrix converter U p First, it enters the primary-side resonant compensation network (i.e., the compensation network). This network can be composed of inductors and capacitors arranged in a specific topology (such as...). LCC , LCL Composed of ( ), and transmitting coil L pThe self-inductance forms a resonant circuit, which on the one hand cancels the reactive component of the coil through resonance compensation, thereby improving the power transmission efficiency, and on the other hand achieves impedance matching, matching the output impedance of the matrix converter with the input impedance of the wireless coupling circuit to ensure maximum power transmission.

[0081] The compensated high-frequency alternating current is then applied to the transmitting coil. L p This generates a high-frequency alternating magnetic field; this magnetic field is transmitted through the mutual inductance between the primary and secondary coils. M Coupled to the secondary receiving coil L s According to the principle of electromagnetic induction, the secondary coil induces a high-frequency AC voltage of the same frequency, thus completing the wireless transmission of electrical energy from the primary side to the secondary side.

[0082] Secondary receiving coil L s The induced high-frequency AC voltage first passes through the secondary-side resonant compensation network. This network, along with... L s This forms a resonant circuit, further optimizing the reactive power compensation and impedance matching on the secondary side, improving the overall efficiency of wireless power transmission, and outputting a stable high-frequency AC voltage. U s .

[0083] Subsequently, high-frequency AC voltage U s The high-frequency AC voltage is fed into the secondary AC-DC switching network, which then converts the AC voltage into a high-frequency AC voltage. U s It is converted to unidirectional DC voltage.

[0084] The rectified DC voltage passes through the battery-side filter capacitor. C b The filtering process removes voltage ripple generated during rectification, outputting a smooth DC voltage that is directly applied to the two ends of the vehicle's 200 power battery to charge it. During the charging process, the control device 130 can monitor the terminal voltage of the vehicle's 200 power battery in real time. U bat The size of the PWM duty cycle of the matrix converter is dynamically adjusted to ensure the safety and efficiency of the charging process.

[0085] Thus, in this embodiment of the application, the AC-AC converter 111 of the charging device 100 can be implemented by a matrix converter and a compensation network, thereby completing the direct conversion from power frequency AC to high frequency AC.

[0086] In addition, it is understandable that Figure 4The specific topologies of the three networks—the primary-side resonant compensation network (i.e., the compensation network), the secondary-side resonant compensation network, and the secondary-side AC-DC switching network—can all be set according to the actual situation.

[0087] For example, regarding Figure 4 For the primary-side resonant compensation network and the secondary-side resonant compensation network mentioned above, please refer to [link to relevant documentation]. Figure 5a , Figure 5b and Figure 5c , Figure 5a , Figure 5b and Figure 5c These are schematic diagrams of the topology of the compensation networks provided in the embodiments of this application. Specifically, the primary-side resonant compensation network and the secondary-side resonant compensation network can be adopted as follows: Figure 5a The series compensation structure shown is such that the compensation capacitor is connected in series with the coil and then connected to the output of the switching network. Alternatively, the primary-side resonant compensation network and the secondary-side resonant compensation network can be configured as follows: Figure 5b The parallel compensation structure shown involves connecting the compensation capacitor in parallel with the load coil and then connecting it to the output of the switching network. Alternatively, the primary-side resonant compensation network and the secondary-side resonant compensation network can be configured as follows: Figure 5c The LCC compensation structure shown is a three-stage resonant network consisting of a series inductor, a parallel capacitor, a series capacitor, and a load coil L.

[0088] For example, regarding Figure 4 For the secondary-side AC-DC switching network, please refer to [link / reference]. Figure 6a , Figure 6b and Figure 6c , Figure 6a , Figure 6b and Figure 6c These are schematic diagrams of the topology of the secondary-side AC-DC switching network provided in the embodiments of this application. Specifically, the secondary-side AC-DC switching network can adopt... Figure 6a The active full-bridge structure shown consists of four N-channel MOSFETs with body diodes. The secondary winding of the transformer is connected to the midpoint of the two bridge arms, and the upper and lower buses are the positive and negative terminals of the DC output, respectively. During operation, during the positive half-cycle of the transformer secondary voltage, the MOSFETs on one side of the upper bridge arm and the MOSFETs on the opposite side of the lower bridge arm are turned on; during the negative half-cycle, the other two MOSFETs are turned on, and the current flows through the low on-resistance MOSFET channels throughout the entire circuit.

[0089] Alternatively, the secondary AC-DC switching network can be adopted. Figure 6bThe semi-active full-bridge structure shown has two rectifier diodes in the upper bridge arm and two N-channel MOSFETs with body diodes in the lower bridge arm. The secondary winding of the transformer is connected to the midpoint of the bridge arm. During operation, during the positive and negative half-cycles, the diodes in the upper bridge arm and the MOSFETs on the opposite side of the lower bridge arm conduct simultaneously, and current is transmitted along the sequential path of transformer winding, diodes, upper bus, load, lower bus, MOSFETs, and transformer winding.

[0090] Alternatively, the secondary-side AC-DC switching network can be adopted. Figure 6c The uncontrolled rectifier bridge structure shown consists of four rectifier diodes. It has no active driving device and operates solely based on the unidirectional conductivity of the diodes. During operation, the two pairs of diodes conduct alternately during the positive and negative half-cycles, and current flows through the PN junctions of the diodes, achieving the conversion from AC to DC.

[0091] It is also understandable that the above Figure 5a , Figure 5b , Figure 5c , Figure 6a , Figure 6b , Figure 6c These are all feasible implementation methods provided in this application, but other specific forms may be adopted in the actual design process, which will not be described in detail here.

[0092] Furthermore, for a clearer illustration of the vehicle 200 charging process in the embodiments of this application, please refer to [link to relevant documentation]. Figure 5c , Figure 6a and Figure 7 , Figure 7 A schematic diagram of a charging system provided for certain embodiments of this application, that is, in Figure 4 Both the primary-side resonant compensation network and the secondary-side resonant compensation network in the text adopt... Figure 5c The LCC compensation structure shown is Figure 4 The secondary AC-DC switching network in the middle adopts Figure 6a When the active full-bridge structure is shown, the charging process of vehicle 200 in this embodiment of the application can be referred to the following exemplary description, namely: The initial AC power output of the power supply unit 300 u g First, through the L g and C g Composition L C. Low-pass filter network. Among them, the series inductor... L g Suppressing high-order harmonics in the input current and improving the power factor on the grid side; parallel capacitors C g The filter absorbs voltage spikes from the mains grid, smoothing the input voltage waveform. The filtered mains frequency AC power is then fed into the two input terminals of the matrix converter.A and N This provides a stable input for subsequent power conversion.

[0093] The control device 130 controls the on / off state of each switching device in the matrix converter, so that the matrix converter converts the received power frequency AC power into high frequency AC power, that is, into high frequency AC voltage. U p .

[0094] High-frequency voltage output by the matrix converter U p The current is fed into the primary-side LCC resonant compensation network, i.e., the current... i Lfp Flow through series inductor L fp In parallel capacitors C fp Parallel resonance is formed at the point of connection, which cancels out part of the reactive power and achieves impedance matching between the output side of the matrix converter and the resonant network.

[0095] Then, the current i p Current flows through the series capacitor C p and transmitting coil L p , C p and L p To create a series resonance, the transmitting coil L p It operates in a resonant state, improving energy transfer efficiency.

[0096] High-frequency current after resonance i p Access L p This generates a high-frequency alternating magnetic field, which is transmitted through the mutual inductance between the primary and secondary coils. M Coupled to the secondary receiving coil L s According to the principle of electromagnetic induction, the secondary coil induces a high-frequency AC voltage of the same frequency, thus completing the wireless transmission of electrical energy from the primary side to the secondary side.

[0097] Secondary coil L s The induced high-frequency AC voltage is fed into the secondary-side LCC resonant compensation network to optimize the secondary-side power transfer efficiency, i.e., current. i s Current flows through the series capacitor C s ,and L sThis forms a series resonance, compensating for the reactive component of the coil and reducing reactive losses on the secondary side. Current flows through the parallel capacitor C fs and series inductors L fs This forms a parallel resonant circuit, achieving impedance matching between the secondary side and the rectifier bridge, thus reducing the input current of the rectifier bridge. i Lfs The waveform is smoother, reducing current distortion during rectification; Compensated high-frequency voltage U s The signal is fed into the secondary rectifier bridge to provide a stable input for the rectification process.

[0098] Control device 130 controls the switching devices of the secondary rectifier bridge. S s1 , S s2 , S s3 , S s4 The conduction timing will convert the high-frequency voltage U s (i.e., high-frequency alternating current) is converted into unidirectional direct current.

[0099] The unidirectional DC current output from the secondary rectifier bridge flows to the battery-side filter capacitor. C b The system performs filtering to remove voltage ripple generated by rectification, outputting a smooth DC voltage. This DC voltage is directly applied to the two ends of the vehicle's 200 power battery to charge the battery.

[0100] The control device 130 monitors the battery terminal voltage in real time. U bat The PWM duty cycle of the matrix converter and the switching timing of the synchronous rectifier bridge are dynamically adjusted to ensure the safety and efficiency of the charging process.

[0101] In some embodiments provided in this application, the AC-AC converter 111 includes a rectifier bridge, a switching circuit, and a compensation network. The switching circuit includes a first switching device, a second switching device, a third switching device, and a fourth switching device. The first output terminal of the rectifier bridge is electrically connected to one end of a third common node, and the other end of the third common node is electrically connected to the first ends of the first and third switching devices. The second output terminal of the rectifier bridge is electrically connected to one end of the fourth common node, and the other end of the fourth common node is electrically connected to the second ends of the second and fourth switching devices. The second ends of the first and second switching devices are electrically connected to form the third output terminal of the switching circuit. The second ends of the third and fourth switching devices are electrically connected to form the fourth output terminal of the switching circuit. The third and fourth output terminals of the switching circuit are electrically connected to the compensation network.

[0102] Specifically, in the power conversion operation of the charging equipment 100 for vehicle 200, the AC conversion unit of the traditional charging equipment 100 adopts a two-stage conversion structure consisting of a PFC converter and a high-frequency DCAC converter. However, this structure has problems such as a large number of components, high cost, large size, large power loss, and low conversion efficiency. For example, the two-stage structure requires the configuration of input inductors and large-capacity bus electrolytic capacitors, which not only occupy equipment installation space but also increase circuit energy consumption and reduce power conversion efficiency.

[0103] Based on this, in the embodiments of this application, the AC-AC converter 111 can be implemented by a rectifier bridge, a switching circuit and a compensation network. In this way, the rectifier bridge can complete the power frequency rectification, the switching circuit composed of four switching devices can complete the high frequency inversion, and the compensation network can achieve resonance matching and power output. This eliminates the need for the PFC power inductor and the large-capacity bus electrolytic capacitor in the traditional two-stage scheme, thus achieving efficient power conversion.

[0104] In some implementations, the rectifier bridge can be understood as the front-stage power conversion component of the AC-AC converter 111, used to convert the low-frequency AC power input from the power supply device 300 into pulsating DC power.

[0105] In some examples, the rectifier bridge can be an uncontrolled rectifier bridge composed of four diodes, which automatically completes power frequency rectification by relying on the unidirectional conduction characteristics of the diodes; or an active rectifier bridge composed of four active switching devices can be used to achieve the rectification function through power frequency synchronous rectification control, thereby further reducing conduction losses.

[0106] In some implementations, the switching circuit can be understood as the conversion component of the AC-AC converter 111, which consists of multiple active power switching devices. By controlling the turn-on and turn-off timing of each switching device in the switching circuit, the input DC power can be inverted into high-frequency AC power of a set frequency.

[0107] In some implementations, the first, second, third, and fourth switching devices in the switching circuit can be understood as four independent power switching branches constituting the switching circuit. Each switching device can be composed of one or more semiconductor switching devices. The four switching devices are arranged in a full-bridge topology to form two sets of bridge arms, and complete the DC to high-frequency AC inverter function through coordinated switching.

[0108] In some examples, the switching devices in the switching circuit can be semiconductor switching devices such as IGBT, Si MOSFET, SiC MOSFET or GaNHEMT, and the specific selection can be flexibly made according to the charging power level, switching frequency and cost requirements.

[0109] In some implementations, the third common node can be understood as the common electrical connection node between the first output terminal of the rectifier bridge and the input terminal of the upper bridge arm of the switching circuit, used to collect the positive electrical energy of the rectified output and provide a unified input potential for the upper bridge arm of the switching circuit.

[0110] In some implementations, the fourth common node can be understood as a common electrical connection node between the second output terminal of the rectifier bridge and the input terminal of the lower bridge arm of the switching circuit, used to collect the negative polarity electrical energy of the rectified output and provide a unified input potential for the lower bridge arm of the switching circuit.

[0111] In some implementations, the third and fourth output terminals can be understood as the midpoint output nodes of the two bridge arms of the switching circuit. They are the output ports of the high-frequency AC power of the switching circuit and are respectively connected to the two input terminals of the compensation network to output the inverted high-frequency AC power to the subsequent circuit.

[0112] In some implementations, the compensation network can be understood as the output optimization component of the AC-AC converter 111, used to optimize the waveform of high-frequency AC power, compensate for reactive power in the circuit, and improve the quality of charging power.

[0113] In some examples, the compensation network can be composed of passive components such as inductors and capacitors, such as LCC compensation and series compensation topologies, to meet the resonant compensation requirements of vehicle wireless charging.

[0114] To more clearly illustrate the circuit topology of the switching circuit in the AC-AC converter 111 and the operating principle of the AC-AC converter 111 in the embodiments of this application, please refer to... Figure 8 , Figure 8 This is a schematic diagram of a charging system provided for certain embodiments of this application. Also please... Figure 8 Based on the above, please refer to the following exemplary description: Specifically, such as Figure 8As shown, the switching circuit in the AC-AC converter 111 consists of four switching devices, namely the first switching device. S p1 Second switching device S p2 Third switching device S p3 and the fourth switching device S p4 .in, S p1 Drain and S p3 The drains of both nodes are connected to the third common node. Figure 8 One end of the rectifier bridge (not shown in the diagram) is connected to the other end of the third common node, and the first output end of the rectifier bridge is connected to the other end of the third common node. S p1 The source pole and S p2 The drains of the circuit are connected to a common node D, and the third output of the switching circuit is led out from the common node D. S p3 The source pole and S p4 The drains of the circuit are connected to a common node E, and the fourth output of the switching circuit is led out from the common node E. S p2 The source pole and S p4 The source poles are all connected to the fourth common node ( Figure 8 One end of the rectifier bridge (not shown in the diagram) is connected to the other end of the fourth common node, and the second output end of the rectifier bridge is connected to the other end of the fourth common node.

[0115] Furthermore, the grid-side power frequency AC power u g First, enter the... L g and C g The low-pass filter network formed by these components suppresses high-order harmonics and electromagnetic interference in the current, resulting in a smooth-wavelength power frequency AC current.

[0116] The filtered alternating current passes through the node A , N The current enters the uncontrolled rectifier bridge, where four diodes conduct alternately according to the power frequency cycle, converting the bidirectional alternating current into unidirectional pulsating direct current. The rectified current then passes through the DC-side filter capacitor. C f The voltage is smoothed to form a stable DC bus voltage, providing power input for the subsequent full-bridge inverter circuit.

[0117] The control device 130 drives the active switching full-bridge (i.e., switching circuit) according to charging requirements, such as target power and voltage. Sp1 , S p2 , S p3 and S p4 The circuit is switched on alternately at a set frequency to allow current to flow from the node. D Flow to Node E Alternatively, the flow could reverse, thereby inverting the DC bus voltage into a high-frequency AC voltage. U p It completes the conversion from industrial frequency AC to high frequency AC.

[0118] High frequency AC voltage U p Input primary-side resonant compensation network (i.e., compensation network), this network and the transmitting coil L p An LC resonant circuit is formed, enabling the circuit to operate in a resonant state. The core function of resonance is to compensate for the reactive power of the coil, improve the power factor, and simultaneously achieve impedance matching, allowing the primary circuit to transfer energy to the secondary circuit with maximum efficiency.

[0119] primary coil L p A high-frequency alternating magnetic field is generated under the excitation of a high-frequency alternating current, and the secondary coil... L s Through mutual induction M Coupled with this magnetic field, according to the law of electromagnetic induction, L s A high-frequency alternating current of the same frequency will be induced in the middle.

[0120] Secondary coil L s The induced high-frequency alternating current enters the secondary-side resonant compensation network, which also operates in a resonant state, further optimizing the power factor on the receiving side, reducing reactive power loss, and outputting a stable high-frequency alternating voltage. U s This provides a reliable input for the subsequent rectifier circuit.

[0121] The secondary-side AC-DC switching network converts high-frequency AC voltage. U s It is converted to unidirectional direct current.

[0122] DC power is filtered by the battery-side filter capacitor. C b The voltage is smoothed, ripple is significantly suppressed, and a stable DC voltage is formed, directly supplying the power battery. U bat Charging. The control device 130 can collect battery voltage and current data in real time, and dynamically adjust the output power by adjusting the switching frequency / duty cycle of the primary-side full bridge to ensure battery safety and charging efficiency.

[0123] Furthermore, it is understandable that, in situations such as Figure 8 In the example shown, the rectifier bridge in the AC-AC converter 111 is implemented based on an uncontrolled rectifier bridge. However, it should be noted that the rectifier bridge in the AC-AC converter 111 can also be implemented based on other topologies. For example, please refer to [link to relevant documentation]. Figure 9 , Figure 9 A schematic diagram of a charging system provided for certain embodiments of this application, i.e. Figure 9 As shown, the rectifier bridge in the AC-AC converter 111 can be understood as an active rectifier bridge (or active switching bridge) consisting of four N-channel MOSFETs with body diodes and performing power frequency synchronous rectification control.

[0124] It is also understandable that Figure 9 The working logic of the charging system shown is... Figure 8 Similarities exist, and to avoid repetition, they will not be elaborated upon here.

[0125] Thus, in this embodiment, the AC-AC converter 111 can be implemented using a rectifier bridge, a switching circuit, and a compensation network. This transforms the charging device's low-frequency to high-frequency AC conversion from a traditional two-stage process to a single-stage process, thereby improving the power conversion efficiency of the charging device 100. Furthermore, it is understandable that, with Figure 4 The primary-side resonant compensation network (i.e., compensation network), secondary-side resonant compensation network, and secondary-side AC-DC switching network are similar in that they are not directly related to the main network. Figure 8 , Figure 9 The specific topologies of the primary-side resonant compensation network (i.e., the compensation network), the secondary-side resonant compensation network, and the secondary-side AC-DC switching network can all be configured according to actual conditions. Please refer to the aforementioned documentation for details. Figure 5a , Figure 5b , Figure 5c , Figure 6a , Figure 6b , Figure 6c To avoid repetition, the relevant explanations will not be elaborated here.

[0126] In some embodiments provided in this application, the AC-AC converter 111 further includes a filter capacitor, and the rectifier bridge is electrically connected to the switching circuit through the filter capacitor.

[0127] Specifically, in the power conversion operation of wireless charging for vehicles, traditional wall-mounted components use a two-stage discrete topology of PFC converter and high-frequency DCAC converter, requiring large-capacity electrolytic bus capacitors, which results in large size, high cost, high loss, and low efficiency. If only a topology directly connecting the rectifier bridge and switching circuit is used, the power output from the rectifier bridge will carry high-frequency harmonics and voltage ripples. This interference directly affects the control accuracy of the switching circuit, disrupts the resonant state of the subsequent compensation network, and leads to poor operational stability and inefficient energy conversion of the charging equipment.

[0128] Based on this, in the embodiments of this application, the AC-AC converter 111 adds a filter capacitor between the rectifier bridge and the switching circuit, so that the two are electrically connected through the filter capacitor, thereby constructing a single-stage AC-AC converter circuit with better filtering effect and more stable operation, and eliminating the impact of harmonic interference on the operation of the charging device 100 while retaining the advantages of single-stage conversion.

[0129] In some implementations, a filter capacitor can be understood as a capacitor placed between the rectifier bridge and the switching circuit to filter out high-frequency harmonics and smooth the voltage waveform.

[0130] In some examples, the filter capacitors are made of thin film material, with small capacitance values, and only perform high-frequency filtering functions. They do not have large-capacity energy storage capabilities, unlike the large-capacity electrolytic bus capacitors in traditional topologies.

[0131] For some examples, please refer to [link / reference]. Figure 8 or Figure 9 That is, a DC-side filter capacitor can be placed between the rectifier bridge and the switching circuit. C f So that the rectified current passes through the DC-side filter capacitor C f The voltage is smoothed to form a stable DC bus voltage, providing power input for the subsequent full-bridge inverter circuit.

[0132] Thus, in this embodiment, a filter capacitor can be added between the rectifier bridge and the switching circuit of the AC-AC converter 111, thereby eliminating high-frequency harmonic interference, improving the working accuracy of the switching circuit and the resonance stability of the compensation network, thereby ensuring the conversion efficiency and operational reliability of wireless charging of the vehicle 200, and improving the overall performance of the charging device 100.

[0133] Please refer to it again. Figure 2-4In some embodiments provided in this application, the charging device 100 further includes a filter circuit 112, the power supply device 300 is electrically connected to the filter circuit 112, the filter circuit 112 is electrically connected to the AC-AC converter 111, and the filter circuit 112 receives the electrical energy input from the power supply device 300 and outputs initial AC power to the AC-AC converter 111.

[0134] Specifically, in the wireless charging operation of vehicle 200, the power frequency AC output directly from the power supply device 300 suffers from harmonic interference, voltage fluctuations, high-frequency noise, and voltage spikes. For example, directly inputting unprocessed power frequency AC into the AC-AC converter 111 reduces the converter's low-frequency to high-frequency conversion accuracy, leading to a decrease in the power factor and an increase in energy loss in the charging device 100. Furthermore, noise and harmonics in the circuit can interfere with the stable operation of the single-stage conversion circuit, failing to meet the streamlined and efficient design requirements of the wireless charging system and affecting the stability and safety of vehicle 200 charging.

[0135] Based on this, in the embodiments of this application, the charging device 100 can achieve power preprocessing by adding a filter circuit 112. Specifically, the filter circuit 112 is connected in series between the power supply device 300 and the AC-AC converter 111. The filter circuit 112 purifies and stabilizes the raw power input from the power supply device 300, providing the AC-AC converter 111 with a regular waveform and stable amplitude, thereby ensuring the stable operation and efficient conversion of the AC-AC converter 111.

[0136] In some implementations, the filter circuit 112 can be understood as an energy preprocessing component of the charging device 100, used to filter out harmonics, noise and voltage spikes in the AC output of the power supply device 300, and to stabilize the waveform and amplitude of the AC.

[0137] In some examples, the filter circuit 112 can be composed of a combination of inductors and capacitors, such as an LC filter topology, which has the characteristics of simple structure and stable filtering effect, and is suitable for the miniaturization design requirements of the vehicle 200 wireless charging device 100.

[0138] For some examples, please refer to [link / reference]. Figure 4 , Figure 7 , Figure 8 and Figure 9 , that is Figure 4 , Figure 7 , Figure 8 and Figure 9 As shown in any of the figures, the filter circuit 112 in the embodiments of this application can be understood as being composed of... L g and C g The filter network consists of [various components]. Lg It is a series filter inductor used to suppress high-order harmonics of the input current and improve the power factor on the input side. C g It is a parallel filter capacitor used to absorb voltage spikes on the mains side and smooth the input current waveform.

[0139] Thus, in this embodiment of the application, a filter circuit 112 can be added between the power supply device 300 and the AC-AC converter 111, so that the AC-AC converter 111 can receive stable and pure initial AC power through the filter circuit 112.

[0140] Corresponding to the above-described charging equipment for vehicles, this application also provides a charging control method for vehicles; please refer to the details below. Figure 10 , Figure 10 This is a schematic flowchart illustrating a charging control method provided in certain embodiments of this application. In this charging control method, the vehicle is electrically connected to the aforementioned charging equipment, and the method specifically includes: 01: The AC-to-AC converter is controlled to convert the initial AC power into the target AC power. 02: Charging the vehicle with target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

[0141] Please see Figure 11 This application provides a charging control device 400. The vehicle charging method of this application can be implemented by the vehicle charging device 400. Specifically, the vehicle charging device 400 includes a control module 410 and a charging module 420. The control module 410 controls an AC-AC converter to convert initial AC power to a target AC power. The charging module 420 charges the vehicle using the target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

[0142] Specifically, existing vehicle wireless charging systems use a three-stage converter topology. The charging control needs to coordinate the operation of the PFC converter, the high-frequency DC-AC converter, and the vehicle-side high-frequency AC-DC converter in sequence. It needs to complete multi-stage conversion control of power frequency AC to DC to high-frequency AC to DC. Not only is the control logic complex and the timing coordination difficult, but it also requires a large number of supporting components, resulting in high energy loss and low charging efficiency in the charging control process. At the same time, it is difficult to optimize the cost and size of the equipment, which cannot meet the control requirements of high efficiency and miniaturization of vehicle charging systems.

[0143] Based on this, in the embodiments provided in this application, after the vehicle is electrically connected to the charging equipment, the AC-AC converter of the charging equipment can be controlled to directly convert the initial AC power provided by the power supply device from low frequency to high frequency to obtain the target AC power that matches the charging requirements, and then the vehicle is charged through the target AC power, which simplifies the charging control process and improves the charging control efficiency.

[0144] In some examples, the charging control method provided in this application can be applied to wireless charging scenarios for various electric vehicles such as pure electric passenger vehicles, electric commercial vehicles, and plug-in hybrid electric vehicles, adapting to charging requirements of different power and voltage.

[0145] In some implementations, a vehicle can be understood as an electric vehicle equipped with a power battery, a charging receiving coil, and a matching power receiving module, which is the power receiving terminal and the charging object of this charging control method.

[0146] In some examples, the vehicles include new energy vehicle types that require external charging, such as household electric vehicles, logistics electric trucks, and electric buses.

[0147] It is understood that the structure and working principle of the AC-AC converter in the embodiments of this application have been described above, and will not be repeated here to avoid repetition.

[0148] To more clearly illustrate the execution process of the charging control method in the embodiments of this application, please refer to the following exemplary description: First, establish a stable electrical connection between the vehicle and the charging equipment to build a complete charging power transmission path. Then, the power supply device electrically connected to the charging device continuously outputs initial AC power and stably transmits the initial AC power to the inside of the charging device; Next, the control device of the charging equipment issues a control command to drive the AC-AC converter to perform low-frequency to high-frequency conversion processing on the initial AC power, and accurately convert the initial AC power of the power frequency into the target AC power that meets the charging requirements of the vehicle. Finally, the charging equipment continuously outputs the converted target AC power to the vehicle, charging the vehicle's power battery through the energy transfer of the target AC power, thus completing the execution and closed-loop regulation of charging control.

[0149] Thus, in this embodiment, the charging device for a vehicle may include a control device and an AC-AC converter for converting AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and then charge the vehicle using the target AC power. This allows the charging device to directly convert low-frequency AC power to high-frequency AC power through a single-stage power conversion. Therefore, the charging device and the vehicle only need to complete two stages of power conversion to wirelessly charge the vehicle. Compared to traditional charging schemes that require three stages of power conversion, the device structure is simpler and the operating cost is lower. Furthermore, it eliminates the input inductor of the power factor correction converter and the large-capacity bus electrolytic capacitor found in traditional schemes, reducing the device size and minimizing power losses caused by multi-stage conversion. This ensures both miniaturization and low cost of the charging device while improving power conversion efficiency and charging stability.

[0150] In some embodiments provided in this application, step 01 includes: Obtain the current reference current and the current input voltage and current input current of the power supply device; Determine the current phase of the power supply device based on the current input voltage; Based on the current reference current, current phase, and current input current, the charging device is controlled so that the AC-AC converter converts the initial AC power and outputs the target AC power.

[0151] The control module 410 provided in this embodiment is also used to acquire the current reference current and the current input voltage and current input current of the power supply device, determine the current phase of the power supply device based on the current input voltage, and control the charging device based on the current reference current, current phase and current input current, so that the AC-AC converter converts the initial AC power and outputs the target AC power.

[0152] Specifically, considering that in a vehicle wireless charging system, the AC-AC converter of the charging equipment needs to be electrically synchronized with the power supply device, if the converter is directly controlled without feedback to perform power conversion, problems such as the input current being out of phase with the power supply device and large current tracking deviation are likely to occur. This will not only reduce the power factor and increase power loss, but also lead to insufficient stability of the output target AC power, which will not meet the needs of efficient vehicle charging.

[0153] Based on this, in some embodiments provided in this application, during the charging control process, the control device of the charging equipment can first obtain the current control reference and the real-time electrical parameters of the grid side, then extract the real-time phase from the grid voltage as the synchronization reference, and finally combine the reference value, phase information and actual sampled current to complete closed-loop control, drive the AC-AC converter to realize the single-stage conversion of power frequency AC to high frequency AC, and take into account power factor correction and output power regulation.

[0154] In some implementations, the current reference current can be understood as an input current target reference signal generated by the control system based on the target charging power, used to provide a tracking target for input current closed-loop control and to limit the amplitude and waveform shape of the input current.

[0155] In some examples, the current reference current can be a sinusoidal current command with the same frequency as the power grid. The amplitude of the current reference current is calculated by the control device based on the target values ​​of voltage and current on the output side. It can be adjusted in real time according to the changes in charging power demand to control the total power obtained by the charging equipment from the power grid.

[0156] In some implementations, the current input voltage can be understood as the instantaneous value of the power frequency AC voltage acquired in real time from the power supply device side. It can reflect the real-time amplitude, polarity and periodic change law of the grid voltage and is the basic input signal for phase-locked loop operation and phase recognition.

[0157] In some examples, the current input voltage can be obtained by sampling the output of a single-phase power grid in real time through a resistor divider voltage sampling circuit. After being converted into a digital signal by an analog-to-digital converter, it is sent to the control unit as the input signal for the phase-locked loop algorithm.

[0158] In some implementations, the current input current can be understood as the instantaneous value of the power frequency AC current collected in real time from the output side of the power supply device. It can reflect the actual current state that the charging device is currently drawing from the power grid and serve as a feedback signal for current closed-loop control, used to compare with the reference current to generate control deviation.

[0159] In some examples, the current input current can be sampled in real time by connecting a current transformer in series in the grid input circuit, or it can be sampled by a high-precision sampling resistor in conjunction with an operational amplifier. The sampling results can reflect the waveform and amplitude changes of the input current in real time.

[0160] In some implementations, the current phase can be understood as the instantaneous phase angle of the grid voltage obtained by tracking the input voltage waveform through a phase-locked loop algorithm. It represents the real-time position of the power frequency voltage within the working cycle and can be used to synchronize the phase of the reference current.

[0161] In some examples, the current phase can be obtained by tracking the zero-crossing point and frequency changes of the input voltage using a phase-locked loop (PLL) algorithm. The angle range of the current phase is typically 0 to 2π, and it is updated cyclically with the grid cycle to achieve phase synchronization between the reference current and the grid voltage.

[0162] To more clearly illustrate the charging control method provided in the embodiments of this application, please refer to [link / reference needed]. Figure 4 , Figure 5a , Figure 5b , Figure 5c , Figure 7 , Figure 12 and Figure 13 , Figure 12 This is a schematic diagram of the control logic for the charging device side provided in certain embodiments of this application. Figure 13 This application provides timing diagrams of drive signals for switching devices on the charging device side, as shown in certain embodiments. Figure 4 , Figure 7 , Figure 12 and Figure 13 Based on the following exemplary description, that is: like Figure 4 or Figure 7 As shown, the AC-AC converter 111 includes a matrix converter and a compensation network. The matrix converter includes four bridge arms, namely... S p1g , S p1h The first upper bridge arm, composed of these two switching devices, is made of S p2g , S p2h The first lower bridge arm, composed of these two switching devices, is... S p3g , S p3h The second upper bridge arm, composed of these two switching devices, is... S p4g , S p4h The two switching devices form the second lower bridge arm. The compensation network can be adopted as follows: Figure 5a The series compensation structure shown, or as... Figure 5b The parallel compensation structure shown, or as... Figure 5c The LCC compensation structure shown.

[0163] And, such as Figure 12 As shown, the control device 130 (or control module 410) in this embodiment includes a phase-locked loop unit, a primary sidewall end control unit, and a pulse width modulation generation unit.

[0164] Furthermore, during the operation of the charging system, the grid voltage... u g (i.e., the current input voltage) passes through the input-side filter network. L g , C g After filtering, the AC input node of the matrix converter is used as an input. A , N On the other hand, it connects to the phase-locked loop (PLL) unit in the control logic. The PLL unit... u g Perform phase-locked loop (PLL) operation to calculate the real-time phase angle of the grid voltage. θ grid (i.e., the current phase).

[0165] Meanwhile, the original side wall end control unit acquires real-time current from the power grid. i g (i.e., current input current) and preset grid reference current i gref (i.e., the current reference current). It is understandable that... i gref The target value for current closed-loop control is set based on the vehicle's charging power demand.

[0166] Subsequently, the charging equipment θ grid For synchronization constraints, with i gref In order to control the target, with i g As the feedback signal, it is calculated using a closed-loop control algorithm to output the phase shift duty cycle. D p Used as a control variable.

[0167] Then, the pulse width modulation generation unit according to D p Generate matrix transformer S p1g , S p1h , S p2g , S p2h , S p3g , S p3h , S p4g , S p4h The driving signals for these eight switching devices, and the timing sequence of these driving signals for these eight switching devices, are as follows: Figure 13 As shown. Among them, Ts During the switching cycle, the duty cycles of the two switching devices in each bridge arm are the same and 0.5. The upper and lower bridge arms in the same group are complementary, and there is a certain dead time. Furthermore, the waveforms of the two upper bridge arms differ in phase. D p T s It is worth noting that when D p As the phase shift time increases, the high-frequency voltage output by the matrix converter also increases. U p An increase in the effective pulse width leads to an increase in output power; conversely, a decrease in the effective pulse width leads to an increase in output power. D p When the phase shift time decreases, the output power also decreases. This can be addressed by adjusting... D p It can achieve continuous adjustment of high-frequency output voltage, thereby matching the different charging power requirements of vehicles.

[0168] Finally, the switching devices of the matrix converter operate according to the timing of the drive signal, directly converting the mains frequency AC power into high frequency AC power (i.e., the target AC power), and outputting it to the node. D , E That is, the input terminal of the primary-side resonant compensation network. High-frequency voltage. U p After inputting into the primary-side resonant network, it is connected to the transmitting coil. L p Resonance, making L p A high-frequency alternating magnetic field is generated through mutual inductance. M Coupled to the secondary receiving coil L s Secondary-side resonant networks and L s Resonance improves power receiving efficiency and outputs high-frequency AC voltage. U s The AC-DC switching network on the secondary side rectifies the current into DC, and then filters it through a capacitor. C b After filtering, it becomes the battery. U bat Charge.

[0169] In addition, it should be noted that the AC-AC converter 111 can be used in addition to the following: Figure 4 or Figure 7 Besides the matrix converter and compensation network combination shown, other devices / networks can also be used, depending on the actual situation. For example, in some embodiments provided in this application, the AC-AC converter 111 can be composed of a rectifier bridge, a switching circuit, and a compensation network.

[0170] To more clearly illustrate the composition of the AC-AC converter 111, consisting of a rectifier bridge, switching circuit, and compensation network, please refer again to [the relevant documentation / reference needed]. Figure 5a , Figure 5b , Figure 5c , Figure 8 , Figure 9 and Figure 14 , Figure 14 This is a timing diagram of the driving signals for the switching devices on the charging device side provided in certain embodiments of this application.

[0171] Specifically, in such Figure 8 or Figure 9 In some of the examples shown, the rectifier bridge in the AC-AC converter 111 can be as follows: Figure 8 The uncontrolled rectifier bridge shown consists of four diodes, which automatically complete the power frequency rectification by relying on the unidirectional conduction characteristics of the diodes. Alternatively, the rectifier bridge in the AC-AC converter 111 can also be as follows: Figure 9 The active rectifier bridge (or active switching bridge) shown consists of four N-channel MOSFETs with body diodes, and can be used for power frequency synchronous rectification control. The switching circuit in the AC-AC converter 111 consists of the first switching device. S p1 Second switching device S p2 Third switching device S p3 and the fourth switching device S p4 These four switching devices make up the whole.

[0172] Furthermore, the compensation network in the AC-AC converter 111 can be adopted as follows: Figure 5a The series compensation structure shown, or as... Figure 5b The parallel compensation structure shown, or as... Figure 5c The LCC compensation structure shown.

[0173] It should also be noted that when the AC-AC converter 111 consists of a rectifier bridge, a switching circuit, and a compensation network, the charging device can also be connected via... θ grid , i gref , i g Output D p In calculation D p During the process, when i g is less than i gref When, the control unit increases D pAs the phase difference of the drive signal increases, the effective output voltage of the full bridge rises, and the transmission power increases. Conversely, when i g Greater than i gref When, the control unit decreases D p As the phase difference of the driving signal decreases, the effective output voltage of the full bridge decreases, and the transmission power decreases.

[0174] It is also understandable that when the AC-AC converter 111 consists of a rectifier bridge, a switching circuit, and a compensation network, i.e., the charging system is as follows: Figure 8 or Figure 9 As shown, in the embodiments of this application, the control device 130 (or control module 410) can generate drive signals for each switching device in the switching circuit to drive each switching device in the switching circuit to operate, so that the AC-AC converter 111 can directly convert the power frequency AC to high frequency AC (i.e., the target AC).

[0175] For example, when the AC-AC converter 111 consists of an uncontrolled rectifier bridge, an active switching circuit, and a compensation network, i.e., the charging system is as follows: Figure 8 As shown, in this embodiment of the application, the control device 130 (or control module 410) can generate an active switching circuit. S p1 , S p2 , S p3 and S p4 The drive signals of these four switching devices are used to drive these four switching devices to operate, thereby directly converting the power frequency AC into high frequency AC (i.e., the target AC). S p1 , S p2 , S p3 and S p4 The timing sequence of the drive signals for these four switching devices is as follows: Figure 14 As shown.

[0176] in, S p1 and S p2 For the left bridge arm complementary signal, S p1 When conducting S p2 Turn off, and vice versa; S p3 and S p4This is a complementary signal for the right bridge arm to avoid shoot-through faults. The drive waveform for each switching device is a square wave with a duty cycle of 0.5. Also, the waveforms between the two upper bridge arms have a phase difference. D p T s The time. D p The larger the value, the greater the phase difference. U p The higher the effective amplitude; D p The smaller the value, the smaller the phase difference. U p The lower the effective amplitude.

[0177] Thus, in this embodiment, the current reference current and the current input voltage and current of the power supply device can be obtained, and the current phase of the power supply device can be determined based on the current input voltage. Based on the current reference current, current phase, and current input current, the charging equipment is controlled so that the AC-AC converter converts the initial AC power and outputs the target AC power. This enables power factor correction and high-frequency inverter output functions, ensuring the input current accurately tracks the grid voltage phase and reducing the harmonic content of the input current, meeting the power quality requirements of grid connection. Furthermore, closed-loop current control can stably adjust the charging power, ensuring the smoothness of the charging process.

[0178] In some embodiments provided in this application, step 01 includes: The current output voltage and current output current are generated by the target alternating current. Based on the current output voltage and current, as well as the obtained reference electrical parameters, the vehicle is controlled to cooperate with the charging equipment for charging.

[0179] Specifically, in the control of wireless charging for vehicles, traditional control schemes only perform single closed-loop control on the wall-end switching stage of the charging equipment, without real-time acquisition and closed-loop feedback of the actual charging parameters at the vehicle end. This can easily lead to problems such as mismatch between the output electrical parameters of the charging equipment and the charging needs of the vehicle's power battery, and large fluctuations in output voltage / current. This not only fails to guarantee charging accuracy and stability, but may also cause safety risks such as overvoltage and overcurrent, while affecting charging efficiency and battery life.

[0180] Based on this, in some embodiments provided in this application, the vehicle can generate real-time output voltage and output current through the target AC power, and after comparing the actual output electrical parameters with the preset reference electrical parameters, the vehicle can be controlled to actively cooperate with the charging equipment to adjust the charging state, thereby ensuring the stability and safety of the charging process.

[0181] In some implementations, the current output voltage can be understood as the real-time DC charging voltage that is actually output to the vehicle's power battery after the target AC power is transmitted wirelessly via magnetic coupling, vehicle-side resonant compensation, and rectification.

[0182] In some implementations, the current output current can be understood as the real-time DC charging current actually output to the vehicle's power battery after the target AC power is transmitted via wireless magnetic coupling, vehicle-side resonance compensation, and rectification.

[0183] In some implementations, the reference electrical parameters can be understood as pre-set voltage or current reference values ​​adapted to the charging characteristics of the vehicle's power battery.

[0184] In some implementations, vehicle-assisted charging can be understood as the vehicle receiving control commands and adjusting the operating parameters of the secondary charging circuit to ensure that the actual charging voltage and current of the power battery stably follow the reference electrical parameters in a coordinated working state.

[0185] To more clearly illustrate the charging control method provided in the embodiments of this application, please refer to [link / reference needed]. Figure 7 , Figure 15 and Figure 16 , Figure 15 This is a schematic diagram of vehicle-side control logic provided in certain embodiments of this application. Figure 16 This is a timing diagram of the vehicle-side switching device drive signals provided for certain embodiments of this application. Specifically, in the secondary coil... L s The high-frequency magnetic field induced on the primary side generates a high-frequency alternating current, which is then transmitted through a series resonant capacitor on the secondary side. C s Filter inductor L fs and filter capacitor C fs After tuning, the resonant filter network outputs high-frequency alternating current. U s To the secondary-side full-bridge converter.

[0186] At this time, the secondary vehicle-side control unit receives the actual battery voltage. u bat (Current output voltage), actual current i bat (i.e., the current output current), and the preset reference voltage. u ref and reference current i ref (i.e., reference electrical parameters), the control duty cycle is calculated through a closed-loop control algorithm. D s .when u bat Less than uref or i bat Less than i ref When, increase D s To improve the effective output voltage / current of the secondary-side full-bridge. Conversely, when u bat Greater than u ref or i bat Greater than i ref When, decrease D s To reduce output and achieve constant voltage / constant current charging.

[0187] Phase-locked unit receives secondary filter inductor current i Lfs The signal is processed, phase information is extracted, and a reference clock signal synchronized with the secondary high-frequency current is generated. The pulse width modulation generation unit receives the phase reference from the phase-locked loop unit and... D s , generate as Figure 16 In the secondary-side full-bridge converter shown S s1 , S s2 , S s3 and S s4 The drive signals for these four switching devices. Among them, S s1 and S s2 The driving signals are complementary. S s3 and S s4 The drive signals are complementary. Furthermore, the switching cycle of each switching device remains... T s Each switching device's drive waveform is a square wave with a duty cycle of 0.5, and there is a certain dead time between each upper and lower bridge arm. Furthermore, the waveforms between the two upper bridge arms differ in phase. D s T s The time.

[0188] Second-side full-bridge converter S s1 , S s2 , S s3 and S s4Operating according to the driving signal timing, the high-frequency AC output from the secondary resonant network is rectified into DC, which is then filtered by the battery-side filter capacitor. C b After smoothing, a stable DC output voltage is achieved. U bat Charge the battery.

[0189] Thus, in this embodiment, the current output voltage and current output current can be generated by the target AC current, and the vehicle can be controlled based on the current output voltage and current output current, as well as the obtained reference electrical parameters, so that the vehicle cooperates with the charging equipment for charging. This allows for vehicle coordinated control by collecting the actual output electrical parameters of the vehicle and combining them with the reference electrical parameters, thereby ensuring the stability and accuracy of the charging voltage and current, matching the charging electrical parameters with the charging needs of the vehicle's power battery, avoiding safety hazards such as overvoltage and overcurrent, and improving the safety and reliability of wireless charging.

[0190] In some embodiments provided in this application, the AC-AC converter includes a matrix converter and a compensation network. The matrix converter and the compensation network are electrically connected. The matrix converter includes multiple bridge arms, each consisting of two anti-parallel series-connected fifth and sixth switching devices. Furthermore, the charging control method provided in the embodiments of this application also includes: When the initial AC current is in the positive half-cycle, the sixth switching device of each bridge arm in the control matrix converter is in the conducting state, so as to realize AC-AC conversion through the fifth switching device of each bridge arm in the matrix converter. When the initial AC current is in the negative half-cycle, the fifth switching device of each bridge arm in the control matrix converter is in the on state, so as to realize AC-AC conversion through the sixth switching device of each bridge arm in the matrix converter.

[0191] The control module 410 in this embodiment is further configured to control the sixth switching device of each bridge arm in the matrix converter to be in the conducting state when the initial AC current is in the positive half-cycle, so as to realize AC-AC conversion through the fifth switching device of each bridge arm in the matrix converter; and to control the fifth switching device of each bridge arm in the matrix converter to be in the conducting state when the initial AC current is in the negative half-cycle, so as to realize AC-AC conversion through the sixth switching device of each bridge arm in the matrix converter.

[0192] Specifically, considering that a single-stage AC-AC converter circuit using a matrix converter will generate significant switching losses and exacerbate device heating if all switching devices are continuously driven to switch at high frequency during operation, the positive and negative half-cycle characteristics of the AC input are not fully utilized, the driving logic is complex and the conversion efficiency is difficult to improve, and the advantages of low cost and high efficiency of single-stage topology cannot be fully realized.

[0193] Based on this, in some embodiments provided in this application, the charging device can detect the phase period of the initial AC power in real time, determine whether it is currently in the positive or negative half-cycle, and control the corresponding switching devices in each bridge arm of the matrix converter to turn on in a targeted manner. Without the need for high-frequency switching of all switching devices, a stable low-frequency to high-frequency AC power conversion can be completed, ensuring efficient transmission of charging power.

[0194] In some implementations, the fifth and sixth switching devices can be understood as two semiconductor switching elements connected in reverse series within each arm of the matrix converter, used to control the on / off state of the power path. For example, please refer to... Figure 4 , Figure 7 , Figure 17a and Figure 17b , Figure 17a This is a timing diagram of the switching device drive signal during the positive half-cycle of the voltage provided in certain embodiments of this application. Figure 17b This is a timing diagram of the switching device drive signal during the negative half-cycle of the voltage provided in certain embodiments of this application.

[0195] Specifically, when the charging system is such as 4 or Figure 7 As shown, the AC-AC converter 111 consists of a matrix converter and a compensation network. The matrix converter includes four bridge arms, namely... S p1g , S p1h The first upper bridge arm, composed of these two switching devices, is made of S p2g , S p2h The first lower bridge arm, composed of these two switching devices, is... S p3g , S p3h The second upper bridge arm, composed of these two switching devices, is... S p4g , S p4h These two switching devices form the second lower bridge arm. S p1g , S p2g , S p3g , S p4g All are fifth-order switching devices. S p1h , S p2h , S p3h , S p4h All of them are sixth-order switching devices.

[0196] like Figure 17a As shown, during the positive half-cycle of the power frequency, the charging equipment can control... S p1h , S p2h , S p3h , S p4h All are on, at this time S p1g , S p2g , S p3g , S p4g Emit PWM, S p1g , S p2g Complementary S p3g , S p4g Complementary S p1g and S p3g There is a phase shift duty cycle between them. D p .

[0197] like Figure 17b As shown, during the negative half-cycle of the power frequency, the charging equipment can control... S p1g , S p2g , S p3g , S p4g All are on, at this time S p1h 、 S p2h 、S p3h 、S p4h Emit PWM, S p1h , S p2h Complementary S p3h , S p4h Complementary S p1h and S p3h There is a phase shift duty cycle between them. D p .

[0198] Thus, in this embodiment, when the initial AC current is in the positive half-cycle, the sixth switching device of each bridge arm in the matrix converter can be controlled to be in the conducting state, so as to realize AC-AC conversion through the fifth switching device of each bridge arm in the matrix converter. When the initial AC current is in the negative half-cycle, the fifth switching device of each bridge arm in the matrix converter can be controlled to be in the conducting state, so as to realize AC-AC conversion through the sixth switching device of each bridge arm in the matrix converter. This reduces the number of high-frequency switching of the matrix converter switching devices, reduces switching losses and device heat generation, simplifies the drive control logic, improves the overall efficiency of the wireless charging system, reduces the hardware cost of the charging device, and reduces the size of the device.

[0199] This application also provides a computer-readable storage medium storing a computer program that, when executed by one or more processors, implements the above-described charging control method.

[0200] This application also provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the above-described charging control method.

[0201] In this specification, the terms "specifically," "furthermore," "particularly," "understandably," etc., refer to specific features, structures, materials, or characteristics described in connection with embodiments or examples that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0202] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this application pertain.

[0203] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A charging device for a vehicle, characterized in that, The charging device includes an AC-AC converter and a control device, wherein the AC-AC converter is used to convert AC power from low frequency to high frequency. The control device is configured to control the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power, and to charge the vehicle through the target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

2. The charging device according to claim 1, characterized in that, The AC-AC converter includes a matrix converter and a compensation network. The matrix converter includes a first upper bridge arm, a first lower bridge arm, a second upper bridge arm, and a second lower bridge arm. Each bridge arm consists of two switching devices connected in reverse series. The first end of the first upper bridge arm and the first end of the second upper bridge arm are both electrically connected to one end of the first common node. The other end of the first common node is electrically connected to the first input terminal of the compensation network. The second end of the first upper bridge arm is electrically connected to the first end of the first lower bridge arm to form the first input terminal of the matrix converter. The second end of the second upper bridge arm is electrically connected to the first end of the second lower bridge arm to form the second input terminal of the matrix converter. The second end of the first lower bridge arm and the second end of the second lower bridge arm are both electrically connected to one end of the second common node. The other end of the second common node is electrically connected to the second input terminal of the compensation network.

3. The charging device according to claim 1, characterized in that, The AC-AC converter includes a rectifier bridge, a switching circuit, and a compensation network. The switching circuit includes a first switching device, a second switching device, a third switching device, and a fourth switching device. The first output terminal of the rectifier bridge is electrically connected to one end of the third common node, and the other end of the third common node is electrically connected to the first end of the first switching device and the first end of the third switching device. The second output terminal of the rectifier bridge is electrically connected to one end of the fourth common node, and the other end of the fourth common node is electrically connected to the second end of the second switching device and the second end of the fourth switching device. The second end of the first switching device is electrically connected to the first end of the second switching device to form the third output terminal of the switching circuit. The second end of the third switching device is electrically connected to the first end of the fourth switching device to form the fourth output terminal of the switching circuit. The third output terminal and the fourth output terminal of the switching circuit are electrically connected to the compensation network.

4. The charging device according to claim 3, characterized in that, The AC-AC converter also includes a filter capacitor, and the rectifier bridge is electrically connected to the switching circuit through the filter capacitor.

5. The charging device according to claim 1, characterized in that, The charging device further includes a filter circuit. The power supply device is electrically connected to the filter circuit, and the filter circuit is electrically connected to the AC-AC converter. The filter circuit receives the electrical energy input from the power supply device and outputs the initial AC power to the AC-AC converter.

6. A charging control method for a vehicle, characterized in that, The vehicle is electrically connected to the charging device according to any one of claims 1-5, and the method includes: The AC-AC converter is controlled to perform the conversion process on the initial AC power to obtain the target AC power. The vehicle is charged using the target AC power, wherein the initial AC power is provided by a power supply device electrically connected to the charging equipment.

7. The charging control method according to claim 6, characterized in that, The process of controlling the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power includes: Obtain the current reference current and the current input voltage and current input current of the power supply device; The current phase of the power supply device is determined based on the current input voltage; Based on the current reference current, the current phase, and the current input current, the charging device is controlled so that the AC-AC converter performs the conversion process on the initial AC power and outputs the target AC power.

8. The charging control method according to claim 7, characterized in that, The process of controlling the AC-AC converter to perform the conversion process on the initial AC power to obtain the target AC power includes: The target alternating current is used to generate the current output voltage and current output current; Based on the current output voltage and current, as well as the obtained reference electrical parameters, the vehicle is controlled to cooperate with the charging equipment for charging.

9. The charging control method according to claim 6, characterized in that, The AC-AC converter includes a matrix converter and a compensation network. The matrix converter is electrically connected to the compensation network. The matrix converter includes multiple bridge arms, each of which consists of two anti-tandem fifth and sixth switching devices. The charging control method further includes: When the initial AC current is in the positive half-cycle, the sixth switching device of each bridge arm in the matrix converter is controlled to be in the conducting state, so as to realize AC-AC conversion through the fifth switching device of each bridge arm in the matrix converter. When the initial AC current is in the negative half-cycle, the fifth switching device of each bridge arm in the matrix converter is controlled to be in the on state, so as to realize AC-AC conversion through the sixth switching device of each bridge arm in the matrix converter.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by one or more processors, implements the charging control method according to any one of claims 6-9.

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