Tram infinite charging device and tram infinite charging system

Abstract

The utility model relates to the field of electric car charging technology discloses electric car unlimited charging device and electric car unlimited charging system, electric car unlimited charging device is connected with the electric car on parking stall, and the electric car includes: receiving coil and battery, receiving coil and battery connect, and the device includes: vehicle identification system is used for detecting the vehicle type and license plate number of parking, and outputs charging confirmation signal when detecting that the vehicle type is electric car, charging request is sent to the vehicle user terminal to the charging confirmation signal receiving charging confirmation signal and outputs charging control signal, calculates the expense of charging, inductive charging system is connected with power end and receiving coil respectively, is used for receiving charging control signal after rising and receiving coil contact connection, and sends to the receiving coil of electric car after converting the electric energy of power end into inductive energy. The application solves the problem that the existing technology needs manual artificial to insert the charging head into the charging port in wired charging.

Description

Technical Field

[0001] This utility model relates to the field of electric vehicle charging technology, specifically to an electric vehicle wireless charging device and an electric vehicle wireless charging system. Background Technology

[0002] With the continuous development and popularization of electric vehicles, the issue of electric vehicle charging has gradually become a problem that people need to face. At present, the mainstream charging method is wired charging at charging stations, but the driver or assistant needs to insert the charging head into the charging port, and it needs to be put back after charging, which is not convenient.

[0003] In summary, existing wired charging technologies require manual insertion of the charging head into the charging port. Utility Model Content

[0004] This invention provides a wireless charging device and system for electric vehicles to solve the problem of the need for manual insertion of the charging head into the charging port in wired charging in the prior art.

[0005] In a first aspect, this utility model provides a wireless charging device for electric vehicles, which is connected to an electric vehicle in a parking space. The electric vehicle includes a receiving coil and a battery, which are connected together. The wireless charging device for electric vehicles includes: The vehicle identification system is used to detect the type and license plate number of a parked vehicle, and outputs a charging confirmation signal when the vehicle type is detected as an electric vehicle. A billing and communication system is used to receive a charging confirmation signal and send a charging request to the vehicle user terminal, and to output a charging control signal after receiving a charging signal, as well as to calculate the charging cost. An inductive charging system is connected to both the power supply and the receiving coil. After receiving a charging control signal, the system rises to make contact with the receiving coil and converts the electrical energy from the power supply into inductive energy, which is then sent to the receiving coil of the tram.

[0006] This application discloses a wireless charging device for electric vehicles. When a vehicle identification system recognizes a vehicle entering a parking space as an electric vehicle, it outputs a charging confirmation signal. Based on this signal, a billing and communication system sends a charging request to the vehicle user and receives the charging signal according to a preset charging method, outputting a charging control signal. Upon receiving the charging control signal, the inductive charging system rises and connects with the receiving coil, converting electrical energy from the power source into inductive energy and sending it to the electric vehicle's receiving coil for wireless charging. This significantly improves the user's charging convenience. Furthermore, the ability of the inductive charging system to rise and fall to contact the receiving coil greatly enhances charging efficiency.

[0007] In some alternative embodiments, the electric vehicle wireless charging device further includes: The vehicle limit lever is equipped with the billing and communication system and the vehicle identification system. The vehicle limit lever is also used to control and restrict the parking position of the vehicle.

[0008] In some alternative embodiments, the limit stop bar is provided with a parking specification diagram.

[0009] In some alternative embodiments, the inductive charging system includes: A boss base is provided at a preset position in the parking space, and the boss base is at a preset height based on the parking level. A charging transmitting coil is disposed on the boss base. The charging transmitting coil is electromagnetically coupled to the receiving coil. The charging transmitting coil is used to output energy to charge the tram.

[0010] In some alternative embodiments, the boss base is liftable, and the top of the charging transmitter coil is provided with a magnetic attraction device for adhering to the vehicle chassis.

[0011] In some alternative embodiments, the inductive charging system further includes: Primary-side control circuit, used to output primary-side control rectified signal; A primary-side rectifier circuit, which is connected to the primary-side control circuit, is used to receive the primary-side control rectification signal and rectify the input AC power into DC power for output. A voltage regulating circuit, which is connected to the primary-side rectifier circuit, is used to regulate the voltage of the received DC power before outputting it. An inverter circuit is connected to the voltage regulation circuit and the charging transmitter coil respectively, and is used to convert DC power into AC power for output.

[0012] In some alternative embodiments, the tram includes: A secondary-side control circuit, wherein the secondary-side control circuit is used to output a secondary-side control rectified signal; The secondary rectifier circuit is connected to the secondary control circuit, the battery, and the receiving coil, respectively, and is used to receive the secondary control rectification signal, rectify the received AC power into DC power, and then output it.

[0013] In some optional embodiments, the primary-side control circuit includes a primary-side modulation and demodulation circuit, a primary-side controller, and a primary-side coupling circuit, and the secondary-side control circuit includes a secondary-side modulation and demodulation circuit, a secondary-side controller, and a secondary-side coupling circuit. The primary-side modulation and demodulation circuit modulates the signal output by the primary-side controller, and the primary-side coupling circuit couples the modulated signal to the charging and transmitting coil. The secondary-side coupling circuit couples the signal received by the receiving coil to the secondary-side modulation and demodulation circuit, and after demodulation by the secondary-side modulation and demodulation circuit, it sends the signal to the secondary-side controller.

[0014] In some alternative embodiments, the tram includes: A battery management system is connected between the battery and the receiving coil to monitor charging data and control charging.

[0015] Secondly, this utility model provides a wireless charging system for electric vehicles, which includes the wireless charging device and the electric vehicle as described above. The trolley includes a receiving coil and a battery, which are connected together. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram illustrating an application scenario according to an embodiment of the present utility model; Figure 2 This is a structural diagram of an electric vehicle wireless charging device according to an embodiment of the present utility model; Figure 3 This is a structural diagram of another electric vehicle wireless charging device according to an embodiment of the present utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] It is understood that before using the technical solutions disclosed in the various embodiments of this utility model, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in this utility model in an appropriate manner in accordance with relevant laws and regulations, and user authorization should be obtained.

[0020] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] With the continuous development and popularization of electric vehicles, the issue of electric vehicle charging has gradually become a problem that people need to face. At present, the mainstream charging method is wired charging at charging stations, but the driver or assistant needs to insert the charging head into the charging port, and it needs to be put back after charging, which is not convenient.

[0022] In summary, existing wired charging technologies require manual insertion of the charging head into the charging port.

[0023] In this embodiment, a wireless charging device for electric vehicles is provided, such as... Figure 1 As shown, the electric vehicle wireless charging device is connected to an electric vehicle in a parking space. The electric vehicle includes a receiving coil and a battery, which are connected together. The electric vehicle wireless charging device includes: The vehicle identification system is used to detect the type and license plate number of a parked vehicle, and outputs a charging confirmation signal when the vehicle type is detected as an electric vehicle. Optionally, the vehicle recognition system includes a geomagnetic sensor (to detect parking space occupancy status), a high-position camera / video stake (to recognize license plate information), and a handheld PDA terminal (to assist in manual data entry), which constitute the data acquisition foundation of the system.

[0024] A billing and communication system is used to receive a charging confirmation signal and send a charging request to the vehicle user terminal, and to output a charging control signal after receiving a charging signal, as well as to calculate the charging cost. Optionally, the billing and communication system uses LoRa / NB-IoT low-power wide-area network to transmit sensor data and 4G / 5G network to transmit video streams, ensuring that information is uploaded to the backend in real time. The backend includes an integrated data processing center (storing vehicle information and transaction records), a billing engine (dynamically calculating fees), and user interaction terminals (owner APP and management screen).

[0025] An inductive charging system is connected to both the power supply and the receiving coil. After receiving a charging control signal, the system rises to make contact with the receiving coil and converts the electrical energy from the power supply into inductive energy, which is then sent to the receiving coil of the tram.

[0026] Specifically, the billing and communication system sends license plate number confirmation information and charging confirmation information to the vehicle user through the terminal. When it receives the charging signal sent by the vehicle user based on the license plate number confirmation information and charging confirmation information, it controls the inductive charging system to rise and send induced energy to the receiving coil.

[0027] Specifically, when a car parks in a parking space, the vehicle recognition system detects and records the vehicle type and license plate number, determining whether the vehicle is an electric vehicle. If it is a regular vehicle, the communication system is not triggered; if it is an electric vehicle, the billing and communication system is triggered to pre-energize it. Then, the system tests whether the electric vehicle has an induction coil and whether it is fully charged. If the vehicle does not have an induction coil or the electric vehicle battery is fully charged, power is cut off. If the vehicle battery is not fully charged, the billing and communication system sends a message to the vehicle user terminal to confirm whether charging is required. If the vehicle user replies that they refuse charging or does not reply within a set time (e.g., 3 minutes), power is not supplied. If charging is confirmed, the charging operation begins.

[0028] Specifically, the inductive charging system has a lifting function. After receiving a charging control signal, it raises the induction coil and connects it to the receiving coil at the bottom of the vehicle, sending energy to the receiving coil. The receiving coil receives the induced energy and stores it in the battery. The inductive charging system lowers the induction coil after charging is complete.

[0029] It should be noted that the vehicle recognition system can pre-bind several vehicles, and can directly charge the bound vehicles based on whether they are fully charged, thus improving convenience.

[0030] Specifically, a geomagnetic sensor detects magnetic field disturbances caused by vehicles and sends a "vehicle present" signal to the gateway; a high-position camera simultaneously captures the license plate, and OCR technology extracts the license plate number for dual verification. The system records the vehicle's entry timestamp and transmits information such as the license plate, parking space number, and entry time to the backend management platform via the transmission network, while simultaneously starting a timer. When the vehicle leaves, the geomagnetic sensor detects the magnetic field returning to normal, triggering the departure time recording; the system automatically calculates the fee based on the parking duration and a preset rate. Vehicle users complete payment via a mobile app, QR code scanning, or ETC contactless payment, with payment information synchronized to the backend in real time, generating an electronic record for archiving. It should be noted that an AI vision algorithm is used, achieving a recognition accuracy of >98%, and supporting low-light environments at night and capturing tilted license plates. Through the payment app's payment API, automatic deduction based on license plate binding is supported, with an average payment time of <30 seconds. The vehicle recognition system processes license plate recognition data locally, reducing cloud transmission load and achieving a response latency of <100ms. Automated management reduces manual intervention and lowers operating costs by approximately 40%; dynamic billing supports time-based rate adjustments, alleviating parking space shortages during peak hours; and data visualization, specifically using GIS (Geographic Information System) maps to display parking space status in real time and support historical data statistical analysis, facilitates the management of parking spaces.

[0031] This application discloses a wireless charging device for electric vehicles. When a vehicle identification system recognizes a vehicle entering a parking space as an electric vehicle, it outputs a charging confirmation signal. Based on this signal, a billing and communication system sends a charging request to the vehicle user and receives a charging signal according to a preset charging method, outputting a charging control signal. Upon receiving the charging control signal, the inductive charging system rises and connects with the receiving coil, converting electrical energy from the power source into inductive energy and sending it to the electric vehicle's receiving coil for wireless charging. This significantly improves charging convenience for users. Furthermore, the ability of the inductive charging system to rise and fall to contact the receiving coil greatly enhances charging efficiency.

[0032] In some alternative implementations, such as Figure 1 As shown, the electric vehicle wireless charging device also includes: The vehicle limit lever is equipped with the billing and communication system and the vehicle identification system. The vehicle limit lever is also used to control and restrict the parking position of the vehicle.

[0033] Specifically, by installing the billing and communication system and the vehicle identification system on the vehicle limit lever and running the wiring inside the vehicle limit lever, the complexity of the wiring layout is greatly reduced, simplifying the equipment. Simultaneously, the vehicle limit lever aligns the vehicle's receiving coil with the inductive charging system, thereby improving charging efficiency.

[0034] In some alternative embodiments, the limit stop lever is provided with a parking specification diagram.

[0035] Specifically, vehicle limit bars can help car owners park in a standardized manner and provide parking references to a certain extent. Alternatively, smart charging parking space indicators can be sprayed on the surface of the limit bars or the parking ground.

[0036] In some alternative implementations, such as Figure 1 and Figure 2 As shown, the inductive charging system includes: A boss base is provided at a preset position in the parking space, and the boss base is at a preset height based on the parking level. A charging transmitting coil is disposed on the boss base. The charging transmitting coil is electromagnetically coupled to the receiving coil. The charging transmitting coil is used to output energy to charge the tram.

[0037] Specifically, refer to Figure 2 The raised platform base is set in the center of the parking space. The raised platform base is set at a preset height based on the parking level to improve waterproofing. The preset height can be 30-50mm, and can be set according to local rainfall conditions.

[0038] In some alternative embodiments, the boss base is liftable, and the top of the charging transmitter coil is provided with a magnetic attraction device for adhering to the vehicle chassis.

[0039] Specifically, the charging transmitter coil can be raised and lowered, and has a magnetic attraction device on top. After charging is confirmed, the transmitter coil is raised and attached to the car chassis through the magnetic attraction device, thereby shortening the sensing distance, improving charging efficiency, and reducing energy loss.

[0040] In some alternative embodiments, the inductive charging system further includes: Primary-side control circuit, used to output primary-side control rectified signal; A primary-side rectifier circuit, which is connected to the primary-side control circuit, is used to receive the primary-side control rectification signal and rectify the input AC power into DC power for output. A voltage regulating circuit, which is connected to the primary-side rectifier circuit, is used to regulate the voltage of the received DC power before outputting it. An inverter circuit is connected to the voltage regulation circuit and the charging transmitter coil respectively, and is used to convert DC power into AC power for output.

[0041] Specifically, the primary-side control circuit includes a primary-side modulation and demodulation circuit. The signal, after being modulated by the primary-side modulation and demodulation circuit, is transmitted through the charging transmitting coil for wireless communication. The primary-side modulation and demodulation circuit transmits signals using multiple frequency modulation methods, and can change the signal transmission frequency.

[0042] Optionally, the voltage regulation circuit can be implemented using a buck DC / DC converter, a boost DC / DC converter, or a buck-boost DC / DC converter.

[0043] In some alternative embodiments, the tram includes: A secondary-side control circuit, wherein the secondary-side control circuit is used to output a secondary-side control rectified signal; The secondary rectifier circuit is connected to the secondary control circuit, the battery, and the receiving coil, respectively, and is used to receive the secondary control rectification signal, rectify the received AC power into DC power, and then output it.

[0044] Specifically, the secondary control circuit controls the secondary rectifier circuit to rectify the AC power into DC power, which is then output to the trolley's battery. The primary control circuit and the secondary control circuit transmit or receive signals through a charging transmitting coil and a receiving coil for wireless communication. The primary control circuit and the secondary control circuit communicate within a preset time period from the zero-crossing point of the AC power.

[0045] In addition, the first and second input terminals of the primary-side rectifier circuit are connected to AC power, and the first and second output terminals of the primary-side rectifier circuit are respectively connected to the first and second input terminals of the voltage regulator circuit; the first and second output terminals of the voltage regulator circuit are respectively connected to the first and second input terminals of the inverter circuit; the first and second output terminals of the inverter circuit are respectively connected to the first and second terminals of the charging transmitter coil. The receiving coil is electromagnetically coupled to the charging transmitter coil, and the first and second terminals of the receiving coil are respectively connected to the first and second input terminals of the secondary-side rectifier circuit; the first and second output terminals of the secondary-side rectifier circuit are both connected to the battery.

[0046] In some feasible implementations, the primary-side control circuit includes a primary-side modulation and demodulation circuit, a primary-side controller, and a primary-side coupling circuit, and the secondary-side control circuit includes a secondary-side modulation and demodulation circuit, a secondary-side controller, and a secondary-side coupling circuit. The primary-side modulation and demodulation circuit modulates the signal output by the primary-side controller, and the primary-side coupling circuit couples the modulated signal to the charging and transmitting coil. The secondary-side coupling circuit couples the signal received by the receiving coil to the secondary-side modulation and demodulation circuit, and after demodulation by the secondary-side modulation and demodulation circuit, it sends the signal to the secondary-side controller.

[0047] The secondary-side control circuit includes a secondary-side modulation and demodulation circuit. The signal is modulated by the secondary-side modulation and demodulation circuit and then transmitted through the receiving coil for wireless communication. The secondary-side modulation and demodulation circuit transmits signals using multiple frequency modulation methods; the secondary-side modulation and demodulation circuit can change the signal transmission frequency.

[0048] Specifically, the primary-side control circuit further includes a primary-side controller and a primary-side coupling circuit; the secondary-side control circuit further includes a secondary-side controller and a secondary-side coupling circuit; wherein, when the primary-side controller sends a signal to the secondary-side controller, the primary-side modulation and demodulation circuit modulates the signal output by the primary-side controller, and the primary-side coupling circuit couples the modulated signal to the charging and transmitting coil, which then transmits the signal and receives it from the receiving coil; the secondary-side coupling circuit couples the signal received by the receiving coil to the secondary-side modulation and demodulation circuit, which then demodulates the signal and sends it to the secondary-side controller; When the secondary-side controller sends a signal to the primary-side controller, the secondary-side modulation and demodulation circuit modulates the signal output by the secondary-side controller, and the modulated signal is coupled to the receiving coil via the secondary-side coupling circuit. After being transmitted by the receiving coil, the signal is received by the charging transmitting coil. The primary-side coupling circuit couples the signal received by the charging transmitting coil to the primary-side modulation and demodulation circuit, and after being demodulated by the primary-side modulation and demodulation circuit, the signal is sent to the primary-side controller.

[0049] It should be noted that the primary-side modulation and demodulation circuit or the secondary-side modulation and demodulation circuit uses FSK (frequency modulation), ASK (amplitude modulation), or PSK (phase modulation) to modulate and demodulate the signal.

[0050] The control terminal of the primary-side controller is connected to the controlled terminal of the primary-side rectifier circuit, the controlled terminal of the voltage regulation circuit, and the controlled terminal of the inverter circuit, respectively; the control terminal of the secondary-side controller is connected to the controlled terminal of the secondary-side rectifier circuit.

[0051] The wireless charging system further includes a primary-side compensation capacitor and a secondary-side compensation capacitor; the first end of the primary-side compensation capacitor is connected to the first output terminal of the inverter circuit, and the second end of the primary-side compensation capacitor is connected to the first end of the charging transmitting coil; the first end of the secondary-side compensation capacitor is connected to the first end of the receiving coil, and the second end of the secondary-side compensation capacitor is connected to the first input terminal of the secondary-side rectifier circuit; the first end of the primary-side modulation and demodulation circuit is connected to the control terminal of the primary-side controller, and the second end of the primary-side modulation and demodulation circuit is connected to the signal terminal of the primary-side coupling circuit; the first coupling terminal of the primary-side coupling circuit is connected to the first end of the primary-side compensation capacitor, and the second coupling terminal of the primary-side coupling circuit is connected to the second end of the charging transmitting coil; the first end of the secondary-side modulation and demodulation circuit is connected to the control terminal of the secondary-side controller, and the second end of the secondary-side modulation and demodulation circuit is connected to the signal terminal of the secondary-side coupling circuit; the first coupling terminal of the secondary-side coupling circuit is connected to the second end of the secondary-side compensation capacitor, and the second coupling terminal of the secondary-side coupling circuit is connected to the second end of the receiving coil.

[0052] In some feasible implementations, such as Figure 3 As shown, the tram includes: A battery management system is connected between the battery and the receiving coil to monitor charging data and control charging.

[0053] Specifically, refer to Figure 3 The battery management system (BMS) uses electromagnetic induction to generate an alternating magnetic field from the charging transmitter coil, which in turn induces a current in the induction coil. This current then charges the vehicle's battery through the BMS. The BMS monitors the battery's voltage / current and temperature in real time, and immediately sends a stop command to cut off the charging process when the battery is fully charged or the temperature is too high.

[0054] Specifically, the first input terminal and the second input terminal of the battery manager are respectively connected to the first output terminal and the second output terminal of the secondary rectifier, and the first output terminal and the second output terminal of the battery manager are both connected to the battery.

[0055] This embodiment provides a wireless charging system for electric vehicles, which includes the wireless charging device and the electric vehicle as described above; the electric vehicle includes a receiving coil and a battery, and the receiving coil and the battery are connected.

[0056] It is worth noting that the beneficial effects of the electric vehicle wireless charging system are similar to those of the electric vehicle wireless charging device described above, and will not be repeated here.

[0057] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A wireless charging device for electric vehicles, characterized in that, The electric vehicle wireless charging device is connected to an electric vehicle in a parking space. The electric vehicle includes a receiving coil and a battery, which are connected together. The electric vehicle wireless charging device includes: The vehicle identification system is used to detect the type and license plate number of a parked vehicle, and outputs a charging confirmation signal when the vehicle type is detected as an electric vehicle. A billing and communication system is used to receive a charging confirmation signal and send a charging request to the vehicle user terminal, and to output a charging control signal after receiving a charging signal, as well as to calculate the charging cost. An inductive charging system is connected to both the power supply and the receiving coil. After receiving a charging control signal, the system rises to make contact with the receiving coil and converts the electrical energy from the power supply into inductive energy, which is then sent to the receiving coil of the tram.

2. The electric vehicle wireless charging device according to claim 1, characterized in that, The electric vehicle wireless charging device also includes: The vehicle limit lever is equipped with the billing and communication system and the vehicle identification system. The vehicle limit lever is also used to control and restrict the parking position of the vehicle.

3. The electric vehicle wireless charging device according to claim 2, characterized in that, The limit stop bar is equipped with a parking regulation diagram.

4. The electric vehicle wireless charging device according to claim 1, characterized in that, The inductive charging system includes: A boss base is provided at a preset position in the parking space, and the boss base is at a preset height based on the parking level. A charging transmitting coil is disposed on the boss base. The charging transmitting coil is electromagnetically coupled to the receiving coil. The charging transmitting coil is used to output energy to charge the tram.

5. The electric vehicle wireless charging device according to claim 4, characterized in that, The boss base is liftable, and the top of the charging transmitter coil is provided with a magnetic attraction device, which is used to attach to the car chassis.

6. The electric vehicle wireless charging device according to claim 4, characterized in that, The inductive charging system also includes: Primary-side control circuit, used to output primary-side control rectified signal; A primary-side rectifier circuit, which is connected to the primary-side control circuit, is used to receive the primary-side control rectification signal and rectify the input AC power into DC power for output. A voltage regulating circuit, which is connected to the primary-side rectifier circuit, is used to regulate the voltage of the received DC power before outputting it. An inverter circuit is connected to the voltage regulation circuit and the charging transmitter coil respectively, and is used to convert DC power into AC power for output.

7. The electric vehicle wireless charging device according to claim 6, characterized in that, The tram includes: A secondary-side control circuit, wherein the secondary-side control circuit is used to output a secondary-side control rectified signal; The secondary rectifier circuit is connected to the secondary control circuit, the battery, and the receiving coil, respectively, and is used to receive the secondary control rectification signal, rectify the received AC power into DC power, and then output it.

8. The electric vehicle wireless charging device according to claim 7, characterized in that, The primary-side control circuit includes a primary-side modulation and demodulation circuit, a primary-side controller, and a primary-side coupling circuit; the secondary-side control circuit includes a secondary-side modulation and demodulation circuit, a secondary-side controller, and a secondary-side coupling circuit. The primary-side modulation and demodulation circuit modulates the signal output by the primary-side controller, and the primary-side coupling circuit couples the modulated signal to the charging and transmitting coil. The secondary-side coupling circuit couples the signal received by the receiving coil to the secondary-side modulation and demodulation circuit, and after demodulation by the secondary-side modulation and demodulation circuit, it sends the signal to the secondary-side controller.

9. The electric vehicle wireless charging device according to claim 1, characterized in that, The tram includes: A battery management system is connected between the battery and the receiving coil to monitor charging data and control charging.

10. A wireless charging system for electric vehicles, characterized in that, The electric vehicle wireless charging system includes the electric vehicle wireless charging device and the electric vehicle as described in any one of claims 1 to 9; The trolley includes a receiving coil and a battery, which are connected together.

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