Vehicle charging device and method
By using a transformer and impedance tuner to regulate the reactance characteristics of the communication line in the electric vehicle charging system, the problem of abnormal charging caused by poor communication quality was solved, and a stable charging process was achieved.
Patent Information
- Application Number
- CN202410548777.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-06
- Publication Date
- 2025-11-07
AI Technical Summary
During the charging process of electric vehicles, there are charging anomalies caused by poor communication quality, such as inability to charge or charging interruption, which are difficult to be effectively resolved by existing technologies.
A combination of transformer and impedance tuner is used to achieve impedance matching by detecting the signal strength of the communication line and adjusting the reactance characteristics of the communication line, thereby improving communication quality.
It effectively reduces the bit error rate of data exchange, avoids charging anomalies, and ensures the stability and continuity of the charging process.
Smart Images
Figure CN120902583A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a charging communication technology, in particular to a vehicle charging device and method. BACKGROUND
[0002] With the increasing awareness of environmental protection, electric vehicles and related infrastructure are increasingly popular. During vehicle charging, the electric vehicle and the charging station can be coupled with each other, and after the charging communication work of the electric vehicle and the charging station is completed, the charging station transmits power to the battery of the electric vehicle for charging.
[0003] During the charging communication work, if the error rate of data exchange is too high, abnormal situations such as the electric vehicle cannot be charged or the charging is interrupted may occur. Although some charging control technical solutions exist, there is still room for improvement. SUMMARY
[0004] An object of the present application is to provide a vehicle charging device and method to effectively improve the charging abnormal situation caused by poor communication quality.
[0005] To achieve the above object, one aspect of the present application provides a vehicle charging device, comprising: a transformer having a first side and a second side, the second side being provided with two communication lines to couple with an electric vehicle; and two impedance tuners, each of the two impedance tuners being connected in parallel to one of the two communication lines, the two impedance tuners being configured to regulate the reactance characteristics of the two communication lines.
[0006] To achieve the above object, one aspect of the present application provides a vehicle charging method applied to a vehicle charging device, the vehicle charging device comprising a transformer and two impedance tuners, the transformer having a first side and a second side, the second side having two communication lines to couple with an electric vehicle, each of the two impedance tuners being connected in parallel to one of the two communication lines, the two impedance tuners being configured to regulate the reactance characteristics of the two communication lines, the method comprising: detecting that the two communication lines connected by the vehicle charging device are coupled with the electric vehicle; performing power line communication between the vehicle charging device and the electric vehicle, so that the vehicle charging device collects the signal strength of a plurality of signal channels of the electric vehicle; monitoring the communication characteristics of the two communication lines according to the signal strength of the plurality of signal channels, so that the signal strength of the two communication lines meets the strength requirement; and in response to the signal strength of the two communication lines meeting the strength requirement, the vehicle charging device performs a charging mode for the electric vehicle.
[0007] The vehicle charging device and method of the present application, the second side of the transformer of the vehicle charging device is provided with two communication lines (with capacitors) to couple the electric vehicle, each impedance tuner of the vehicle charging device is connected in parallel with one communication line, two impedance tuners are configured to regulate the reactance characteristics of the two communication lines, for example, each of the two impedance tuners includes at least one branch path (including a switch and a capacitor), each of the at least one branch path is connected in parallel with the capacitor of the communication line. Therefore, according to the signal strength of the communication line, the capacitors of the appropriate number of branch paths can be gradually controlled to be connected with the capacitors of the communication line to adjust the impedance of the communication line, so that the vehicle charging device and the electric vehicle can communicate with each other in the state of approaching impedance matching, and the abnormal situation that the electric vehicle cannot be charged or the charging is interrupted due to the too high bit error rate of data exchange can be avoided. BRIEF DESCRIPTION OF DRAWINGS
[0008] Figure 1 is a schematic diagram of a vehicle charging system to which embodiments of the present application can be applied.
[0009] Figure 2 is Figure 1 is a schematic diagram of a first signal transmission mode of the vehicle charging system shown.
[0010] Figure 3 is Figure 2 is a schematic diagram of the power spectral density distribution profile of the communication line of the first charging station example shown.
[0011] Figure 4 is Figure 2 is a schematic diagram of the power spectral density distribution profile of the communication line of the second charging station example shown.
[0012] Figure 5 is Figure 1 is a schematic diagram of a second signal transmission mode of the vehicle charging system shown.
[0013] Figure 6a and Figure 6b is Figure 5 is a schematic diagram of the equivalent circuit and insertion loss of the first charging station example shown.
[0014] Figure 7a and Figure 7b is Figure 5 is a schematic diagram of the equivalent circuit and insertion loss of the second charging station example shown.
[0015] Figure 8 is Figure 1 is a schematic diagram of the signal strength of a plurality of signal channels obtained by a plurality of charging station examples shown.
[0016] Figure 9 is a block schematic diagram of the vehicle charging device of the embodiments of the present application.
[0017] Figure 10 is Figure 9 a schematic diagram of a switch and capacitor connection configuration in a branch path.
[0018] Figure 11 is a flowchart diagram of a vehicle charging method according to an embodiment of the present application.
[0019] Legend:
[0020] 10, 20, 50, 90, 100: vehicle charging system
[0021] 11, 21, 51: charging station
[0022] 12, 22, 52, 9B, 10B: electric vehicle
[0023] 13, 211, 511: controller
[0024] 30, 40: PSD profile curve example
[0025] 91, 101, 212, 512: transformer
[0026] 92, 102: impedance tuner
[0027] 921, 1021: branch path
[0028] 23, 53, 93, 103: communication line
[0029] 513: bandpass filter
[0030] 60a, 70a: equivalent circuit example
[0031] 60b, 70b: insertion loss curve example
[0032] 80: signal strength curve example
[0033] 94, 104: first capacitor
[0034] 95, 105: switch
[0035] 96, 106: second capacitor
[0036] 9A, 10A: vehicle charging device
[0037] 9C: network
[0038] 9D: cloud computing platform
[0039] 110: vehicle charging method example
[0040] 111, 112, 113, 114, 115: step
[0041] SPI_TX+, SPI_TX-, SPI_RX+, SPI_RX-, TXOUT_P, TXOUT_N, RXIN_P, RXIN_N: Signal lines
[0042] C1, C2, C3: Curves
[0043] CP: Control lead wire
[0044] PE: Protective grounding wire
[0045] CTL: Control Terminal
[0046] CN1, CN2: Connecting ends
[0047] VD: Power supply terminal
[0048] VDD: DC power supply
[0049] GND: Ground terminal
[0050] R: Resistor
[0051] M1: Sampling point Detailed Implementation
[0052] To make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
[0053] like Figure 1 As shown, in the vehicle charging system 10 (e.g., a combined charging system (CCS)), the charging station (Electric Vehicle Supply Equipment, EVSE) 11 and the electric vehicle (EV) 12 can be coupled to each other. For example, the electric vehicle 12 includes vehicles such as motorcycles or cars. The charging gun of the charging station 11 and the socket of the electric vehicle 12 form a coupler connection. After the electric vehicle 12 and the charging station 11 complete the charging communication operation, the charging station 11 transmits power to the battery of the electric vehicle 12 to charge it. During the charging communication operation, if the controller 13 lacks an effective compatibility control or optimization mechanism, such as adjusting to the differences in the coupler formed by different charging guns (e.g., different wire lengths or wire diameters), and if the bit error rate of data exchange is too high in the coupler connection state, lacking the ability to adapt to data communication compatibility, abnormal situations will occur. For example, the charging communication operation cannot be completed, resulting in abnormal situations such as the electric vehicle being unable to charge or charging being interrupted, leading to a poor user experience.
[0054] For example, taking the Power Line Communication (PLC) protocol as an example, during the charging communication operation, the communication mode between the charging station and the electric vehicle can be full-duplex mode, allowing the charging station and the electric vehicle to transmit data bidirectionally at the same time.
[0055] like Figure 2 As shown, in the first signal transmission mode, in the vehicle charging system 20, the controller 211 of the charging station 21 can transmit signals to the electric vehicle 22 via signal lines (such as TXOUT_P and TXOUT_N) through the transformer 212 and communication line 23. For example, the communication line 23 can be a control pilot line (CP) and a protective earth line (PE). In this case, if there is an impedance mismatch between the charging station 21 and the electric vehicle 22, signal attenuation will occur during communication. For example, the charging station 21 can use a sweep method to obtain the signal strength of multiple signal channels between the charging station 21 and the electric vehicle 22, so that the charging station 21 can obtain a power spectral density distribution profile (PSD profile) of a specific signal.
[0056] In one application example, Figure 3 Example 30 shows a PSD distribution profile curve of a charging station controller obtained from a communication line (such as CP) via channel 9 (CH9), where the signal strength is mostly below -40 dBm, for example, the signal strength at sampling point M1 is -43.01 dBm. In another application example, Figure 4 Example 40 shows a PSD distribution profile curve obtained by the controller of another charging station from a communication line (such as CP), where the signal strength is completely below -40dBm, for example, the signal strength at sampling point M1 is -45.71dBm. Figure 3 and Figure 4 The signal strength of the two charging stations shown has a difference of about 6dB.
[0057] like Figure 5 As shown, in the second signal transmission mode, in the vehicle charging system 50, the controller 511 of the charging station 51 can receive signals from the electric vehicle 52 via signal lines (such as RXIN_P and RXIN_N) through a bandpass filter (RX_BPF) 513 and a transformer 512 via a communication line 53. For example, the communication line 53 can be a control lead (CP) and a protective ground (PE) wire. At this time, if there is an impedance mismatch between the charging station 51 and the electric vehicle 52, it will cause signal attenuation during communication.
[0058] For example, the insertion loss of the communication lines (such as CP and PE) in the coupler loop can be obtained from the transceiver bidirectional channel (such as CH57). Figure 6aand Figure 6b An equivalent circuit example 60a and an insertion loss curve example 60b of a charging station are shown, respectively, the insertion loss curve example 60b shows that the insertion loss (S21) of the equivalent circuit example 60a is about -20.49 dB in the frequency band of 150 kHz to 30 MHz; Figure 7a and Figure 7b An equivalent circuit example 70a and an insertion loss curve example 70b of another charging station are shown, respectively, the insertion loss curve example 70b shows that the insertion loss (S21) of the equivalent circuit example 70a is about -25.17 dB in the frequency band of 150 kHz to 30 MHz, wherein, Figure 6b and Figure 7b The insertion loss of the two charging stations shown has a difference of about 5 dB.
[0059] Figure 8 A signal strength curve example 80 of a plurality of signal channels (such as carrier channels CH0-CH57) obtained from a plurality of charging stations is shown, wherein three curves C1, C2, C3 all show the trend that the signal strength decreases as the carrier channel (CHx, x = 0-57) frequency increases, wherein the signal strength of about two-thirds of the channels is lower than -31 dB, and the received signal strength (such as CH57) distribution profile of the communication line (such as CP) of the coupler loop is about -60 dB to -66 dB (lower than the range of -20 dB to -39 dB).
[0060] From the above, during the charging communication operation, the charging station and the electric vehicle communicate with each other via two communication lines (such as CP and PE), if the impedance between the charging station and the electric vehicle is not matched, it will cause signal attenuation during communication, which will cause the communication operation to fail, and further derive the abnormal charging situation.
[0061] For example, in this paper, power line communication (PLC) is taken as an example of charging communication technology, such as based on ISO-15118-3 / IEC-61851-1 specification. Among them, in the charging station, the two communication lines can be the control pilot line (CP) and the protective earth line (PE), and the two communication lines have capacitive characteristics, which is a key factor affecting the charging communication operation. The reason is at least because the charging station needs to provide power to electric vehicles of different brands, and the impedance states of various electric vehicles are not the same.
[0062] Therefore, in order to avoid the impedance mismatch between the charging station and the electric vehicle, the charging station needs to have the communication impedance tuning capability to match electric vehicles with different impedance states, so that in the case of coupling between the charging station and the electric vehicle to form a coupler, the impedance of the charging station and the electric vehicle on both sides of the coupler tends to match, avoiding serious signal attenuation caused by impedance mismatch, so as to facilitate the completion of the charging communication operation.
[0063] As mentioned above, the present application provides a solution, for example, during the charging communication operation, the charging station and the electric vehicle communicate with each other via two communication lines (such as CP and PE), and the communication line (such as CP and PE) forms a coupler in an open loop working mode. The control scheme of impedance tuning of the communication line (such as CP and PE) can be used. The following is an example, but not limited thereto.
[0064] For example, based on the characteristics of the communication line itself, the communication line impedance tuning mode can be to tune the reactance characteristics (including inductance and capacitance) of the communication line. When the charging station and the electric vehicle form a coupler in the data transmission mode, the signal strength of the communication line (such as CP and PE) is obtained via a specific way (such as scanning a specific channel or executing a specific instruction by the controller). For example, the controller of the charging station issues a "CM_ATTEN_CHAR.IND" instruction to receive the "ATTEN_PROFILE" content as signal attenuation distribution profile information. In this way, the signal characteristics of the communication line can be quickly obtained.
[0065] Accordingly, the present application can provide a control scheme with self-tuned impedance to facilitate the data transmission mode (or diagnostic adjustment program), so that the charging station and the electric vehicle form a coupler with a closed loop detection communication line (such as CP and PE) adjustment impedance function to improve the data transmission quality, thereby avoiding the situation that the communication process cannot be completed due to signal attenuation and charging abnormality.
[0066] In an embodiment, after the relevant data is collected, it can also be used to understand the impedance matching information of the communication line (such as CP and PE) of different electric vehicles, so as to evaluate the communication line characteristics suitable for different vehicles, and to develop a charging impedance tuning scheme suitable for different vehicles, so as to improve the charging compatibility and adaptability, and to achieve the technical effect of optimizing the vehicle charging process.
[0067] The present application provides a solution based on the above scheme, and the following is an example, but not limited thereto.
[0068] In one aspect, as shown in Figure 9 The present application provides a vehicle charging device, for example, in a vehicle charging system 90 (such as CCS), the vehicle charging device 9A and the electric vehicle 9B are coupled to each other, and the vehicle charging device 9A can be configured to form a charging station of a vehicle (such as a motorcycle or a car). The vehicle charging device 9A includes a transformer 91 and two impedance tuners 92.
[0069] For example, as shown in Figure 9As shown, transformer 91 has a first side and a second side. The first side of transformer 91 can transmit signals from electronic devices via signal lines (such as the transmit signal lines (SPI_TX+ and SPI_TX-) and receive signal lines (SPI_RX+ and SPI_RX-) of a Serial Peripheral Interface (SPI). The first side of transformer 91 can receive signals from a controller (such as a power line communication chipset, see [reference]). Figure 2 211 and Figure 5 The controller can collect the signal strength of multiple signal channels as the basis for communication and control. The second side of the transformer 91 is provided with two communication lines 93 to couple to the electric vehicle 9B.
[0070] For example, such as Figure 9 As shown, each of the two impedance tuners 92 is connected in parallel to one of the two communication lines 93. The two impedance tuners 92 are configured to adjust the reactance characteristics of the two communication lines 93. For example, each impedance tuner 92 may include at least one branch path 921 for adjusting the reactance characteristics of the communication line 93, as illustrated below.
[0071] For example, such as Figure 9 As shown, each communication line 93 has a first capacitor 94, and each impedance tuner 92 includes at least one branch path 921 connected in parallel with the first capacitor 94. For example, each branch path 921 includes a switch 95 and a second capacitor 96 connected in series. The switch 95 of each branch path 921 can be configured to cause the first capacitor 94 and the second capacitor 96 to form a parallel circuit or an open circuit according to a control signal from a controller (e.g., a PLC chipset) to gradually adjust (e.g., increase or decrease) the number of second capacitors 96 connected in parallel with the first capacitor 94 to regulate the equivalent capacitance value of the communication line 93, for example, from 10nF to 20nF, but not limited thereto.
[0072] like Figure 9As shown, the more the switches 95 of the branch path 921 are configured to be turned on, the more the second capacitors 96 are formed in a loop with the first capacitor 94, so that the equivalent capacitance value of the communication line 93 is larger, and the equivalent capacitive reactance (ZC) of the communication line 93 is higher; the less the switches 95 of the branch path 921 are configured to be turned on, the less the second capacitors 96 are formed in a loop with the first capacitor 94, so that the equivalent capacitance value of the communication line 93 is smaller, and the equivalent capacitive reactance (ZC) of the communication line 93 is lower. Therefore, the vehicle charging device 9A can control the number of the second capacitors 96 formed in a loop with the first capacitor 94 through the switches 95 of each branch path 921 as a basis for adjusting the reactance characteristics of the communication line 93 in response to the signal strength of the communication line 93.
[0073] In the process of adjusting the signal strength of the communication line, the signal frequency of the communication line is relatively high (for example, in the frequency range of 150 kHz to 30 MHz), and therefore, in order to be able to adjust the impedance state of the communication line in real time in response to the signal strength of the communication line, the selection of the switch needs to take into account the signal frequency of the communication line. Here, only a branch path included in the impedance tuner is taken as an example for illustration, but the present application is not limited thereto.
[0074] As shown, Figure 10 The vehicle charging system 100 includes a vehicle charging device 10A and an electric vehicle 10B, the vehicle charging device 10A includes a transformer 101 and two impedance tuners 102, each of the two impedance tuners 102 is connected in parallel to one of the two communication lines 103, each communication line 103 has a first capacitor 104, and each impedance tuner 102 includes at least one branch path 1021 Figure 10 Only one branch path 1021 is shown. For example, each branch path 1021 includes a switch 105 and a second capacitor 106, the switch 105 can be a high-frequency switching element, for example, the operating frequency range of the switch 105 includes 150 kHz to 30 MHz, but the present application is not limited thereto.
[0075] As shown, Figure 10 In order to ensure the switching speed of the switch and avoid factors such as signal interference, the switch 105 can be a chip-type switch, for example, the chip-type switch has a control terminal CTL and two connection terminals CN1 and CN2, the second capacitor 106 is connected between one of the two connection terminals CN1 and CN2 (such as CN1) and one end of the first capacitor 104, and the other of the two connection terminals CN1 and CN2 (such as CN2) is connected to the other end of the first capacitor 104; in addition, Figure 10As shown, switch 105 may also include other configurations, such as a power supply terminal VD (for external DC power supply VDD) and several ground terminals GND (for electrical grounding). A resistor R may be provided between the control terminal CTL and the ground terminal GND so that the control terminal CTL can maintain a suitable control voltage difference to control the switching state between the two connection terminals CN1 and CN2 to be on or off.
[0076] Please refer to the following: Figure 9 As shown, the vehicle charging device 9A can also be coupled to the cloud computing platform 9D via network 9C. For example, the charging gun plug provided by the vehicle charging device 9A can be inserted into the socket of the electric vehicle 9B. When the vehicle charging device 9A and the electric vehicle 9B form a coupler, the vehicle charging device 9A can collect signal strength information as a basis for whether to adjust the impedance of the communication line, and can also collect vehicle-related information (such as brand or model). The information collected by the vehicle charging device 9A can be aggregated to the cloud computing platform 9D via network 9C for big data analysis to find the appropriate impedance matching scheme for different vehicles in the charging communication process. Subsequently, for similar vehicles, the vehicle charging device 9A can also refer to a recommended impedance matching scheme (such as one provided by the cloud computing platform) to adjust the impedance matching state of the communication line in order to successfully complete the charging communication operation and proceed with the subsequent charging mode.
[0077] On the other hand, such as Figure 11 As shown, this embodiment of the invention provides a vehicle charging method example 110, which can be applied to the aforementioned vehicle charging device (e.g., Figure 9 The vehicle charging device 9A shown can be configured as an electric vehicle charging station. Example 110 of the vehicle charging method includes steps 111 to 115. Examples are given below, but are not limited thereto.
[0078] like Figure 11 As shown, in step 111, the electric vehicle is coupled to the charging station, for example, Figure 9 The vehicle charging device 9A shown is connected to the two communication lines 93 of the vehicle charging device 9A and coupled to the electric vehicle 9B. Then, step 112 is performed.
[0079] like Figure 11 As shown, in step 112, power line communication is performed, for example, Figure 9 The vehicle charging device 9A shown communicates with the electric vehicle 9B via power line communication (PLC) so that the vehicle charging device 9A can collect the signal strength of several signal channels of the electric vehicle 9B. Subsequently, step 113 is performed.
[0080] like Figure 11 As shown, in step 113, the communication line impedance is matched and tuned, for example, Figure 9The vehicle charging device 9A monitors the communication characteristics of the communication line 93 according to the signal strength of the signal channels, so that the signal strength of the communication line 93 meets the strength requirement, for example, the signal strength of the communication line 93 is lower than a signal strength threshold, such as -31dB, but not limited thereto. Figure 9 The vehicle charging device 9A calculates the average signal strength according to the signal strength of the signal channels, such as the average signal strength is equal to the sum of the signal strength divided by the number of the signal strength, and the vehicle charging device 9A confirms that the signal strength of the communication line 93 meets the strength requirement according to the average signal strength and the signal strength threshold, such as the controller of the vehicle charging device 9A determines whether the average signal strength is lower than the signal strength threshold, if yes, the controller of the vehicle charging device 9A gradually adjusts the impedance of the communication line 93, such as the vehicle charging device 9A increases the equivalent capacitance value of the communication line 93 by a predetermined amount, such as by increasing the number of parallel capacitors, so that the impedance matching between the vehicle charging device 9A and the electric vehicle 9B is approached, the average signal strength can be improved, and the above calculation and determination steps are performed again, if no, the controller of the vehicle charging device 9A confirms that the signal strength of the communication line 93 meets the strength requirement, and then step 114 is performed.
[0081] As shown in FIG. 1, the vehicle charging method 110 includes step 113, determining whether the signal strength of the communication line 93 meets the strength requirement, for example, the signal strength of the communication line 93 is lower than a signal strength threshold, such as -31dB, but not limited thereto. Figure 11 As shown in FIG. 1, step 114, the communication enters the charging mode, for example, as shown in FIG. 2, in response to the signal strength of the communication line 93 meeting the strength requirement, the vehicle charging device 9A enters the charging mode. Figure 9 As shown in FIG. 1, the vehicle charging method 110 includes step 115, completing the charging, for example, as shown in FIG. 3, in the charging mode, the electric vehicle 9B can feed back the power information to the vehicle charging device 9A, if the vehicle charging device 9A detects that the battery power of the electric vehicle 9B is greater than or equal to a power threshold, the charging mode can be terminated, for example, the vehicle charging device 9A can output the charging completion information, such as a display screen or generate a sound effect or send a message, etc., so that the user knows that the electric vehicle 9B is in the charging completion state.
[0082] As shown in FIG. 1, the vehicle charging method 110 includes step 115, completing the charging, for example, as shown in FIG. 3, in the charging mode, the electric vehicle 9B can feed back the power information to the vehicle charging device 9A, if the vehicle charging device 9A detects that the battery power of the electric vehicle 9B is greater than or equal to a power threshold, the charging mode can be terminated, for example, the vehicle charging device 9A can output the charging completion information, such as a display screen or generate a sound effect or send a message, etc., so that the user knows that the electric vehicle 9B is in the charging completion state. Figure 11 As shown in FIG. 1, the vehicle charging method 110 includes step 115, completing the charging, for example, as shown in FIG. 3, in the charging mode, the electric vehicle 9B can feed back the power information to the vehicle charging device 9A, if the vehicle charging device 9A detects that the battery power of the electric vehicle 9B is greater than or equal to a power threshold, the charging mode can be terminated, for example, the vehicle charging device 9A can output the charging completion information, such as a display screen or generate a sound effect or send a message, etc., so that the user knows that the electric vehicle 9B is in the charging completion state. Figure 9
[0083] In summary, the vehicle charging device and method of the present application, the second side of the transformer of the vehicle charging device is provided with two communication lines (with capacitors) to couple the electric vehicle, each impedance tuner of the vehicle charging device is connected in parallel with a communication line, two impedance tuners are configured to regulate the reactance characteristics of the two communication lines, for example, each of the two impedance tuners includes at least one branch path (including a switch and a capacitor), and each of the at least one branch path is connected in parallel with the capacitor of the communication line. Therefore, according to the signal strength of the communication line, the capacitors of the appropriate number of branch paths can be gradually controlled to be connected with the capacitor of the communication line to adjust the impedance of the communication line, so that the vehicle charging device and the electric vehicle can communicate with each other in the state of approaching impedance matching, and the abnormal situation that the electric vehicle cannot be charged or the charging is interrupted due to the high bit error rate of data exchange can be avoided.
[0084] Although the present application has been disclosed with preferred embodiments, any person skilled in the art can make various changes and modifications without departing from the concept and scope of the present application, and therefore the protection scope of the present application shall be subject to the claims.
Claims
1. A vehicle charging device, comprising: a transformer having a first side and a second side, the second side having two communication lines to couple an electric vehicle; and two impedance tuners, each of the two impedance tuners being connected in parallel to one of the two communication lines, the two impedance tuners being configured to regulate a reactance characteristic of the two communication lines.
2. The vehicle charging device of claim 1, wherein each of the two communication lines has a first capacitor, each of the two impedance tuners comprises at least one branch path, each of the at least one branch path being connected in parallel to the first capacitor.
3. The vehicle charging device of claim 2, wherein each of the at least one branch path comprises a switch and a second capacitor, the switch being connected in series to the second capacitor.
4. The vehicle charging device of claim 3, wherein the switch is configured to cause the first capacitor and the second capacitor to form a parallel loop or open circuit according to a control signal from a controller.
5. The vehicle charging device of claim 3, wherein the switch is a high frequency switching element.
6. The vehicle charging device of claim 5, wherein a frequency range of operation of the high frequency switching element comprises 150 kHz to 30 MHz.
7. The vehicle charging device of claim 5, wherein the high frequency switching element is a chip-type switch and has a control terminal and two connection terminals, the second capacitor being connected between one of the two connection terminals and one end of the first capacitor, the other of the two connection terminals being connected to the other end of the first capacitor.
8. The vehicle charging device of claim 1, wherein the two communication lines comprise a control pilot line and a protection ground line.
9. The vehicle charging device of claim 1, wherein the vehicle charging device is coupled to a cloud computing platform via a network.
10. A vehicle charging method applied to a vehicle charging device, the vehicle charging device comprising a transformer and two impedance tuners, the transformer having a first side and a second side, the second side having two communication lines to couple an electric vehicle, each of the two impedance tuners being connected in parallel to one of the two communication lines, the two impedance tuners being configured to regulate a reactance characteristic of the two communication lines, the method comprising: detecting that the two communication lines of the vehicle charging device are coupled to the electric vehicle; the vehicle charging device performing power line communication with the electric vehicle for the vehicle charging device to collect signal strengths of a plurality of signal channels of the electric vehicle; the vehicle charging device monitoring communication characteristics of the two communication lines according to the signal strengths of the plurality of signal channels, so that the signal strengths of the two communication lines meet a strength requirement; and in response to the signal strengths of the two communication lines meeting the strength requirement, the vehicle charging device performing a charging mode for the electric vehicle.
11. The vehicle charging method of claim 10, wherein the vehicle charging device monitoring communication characteristics of the two communication lines according to the signal strengths of the plurality of signal channels, so that the signal strengths of the two communication lines meet the strength requirement, comprises: the vehicle charging device calculating a signal strength average according to the signal strengths of the plurality of signal channels; and the vehicle charging device monitoring the signal strength average to meet the strength requirement. The vehicle charging device determines whether the average signal strength is lower than a signal strength threshold value. If the determination is positive, the vehicle charging device causes the equivalent capacitance value of the two communication lines to increase by a predetermined amount, and the calculation and determination are performed again. If the determination is negative, the vehicle charging device determines that the signal strength of the two communication lines meets the strength requirement.
12. The vehicle charging method of claim 11, wherein the vehicle charging device determines whether the average signal strength meets the strength requirement based on the average signal strength and the signal strength threshold value, comprising: The vehicle charging device determines whether the average signal strength is lower than the signal strength threshold value. If the determination is positive, the vehicle charging device causes the equivalent capacitance value of the two communication lines to increase by a predetermined amount, and the calculation and determination are performed again. If the determination is negative, the vehicle charging device determines that the signal strength of the two communication lines meets the strength requirement.
13. The vehicle charging method of claim 11, wherein the signal strength threshold value is -31 dB.
14. The vehicle charging method of claim 10, wherein the vehicle charging device is coupled to a cloud computing platform via a network, the method further comprising: The vehicle charging device collects characteristic information of the electric vehicle and transmits the characteristic information to the cloud computing platform; The cloud computing platform generates a charging scheme for the vehicle charging device based on the characteristic information; and The vehicle charging device charges the electric vehicle based on the charging scheme.
15. The vehicle charging method of claim 10, wherein each of the two communication lines has a first capacitor, and each of the two impedance tuners includes at least one branch path, each of the at least one branch path being connected in parallel with the first capacitor.
16. The vehicle charging method of claim 15, wherein each of the at least one branch path includes a switch and a second capacitor, the switch and the second capacitor being connected in series.
17. The vehicle charging method of claim 16, wherein the switch is configured to cause the first capacitor and the second capacitor to form a parallel loop or an open circuit based on a control signal from a controller.
18. The vehicle charging method of claim 16, wherein the switch is a high-frequency switching element.
19. The vehicle charging method of claim 18, wherein the high-frequency switching element has an operating frequency range of 150 kHz to 30 MHz.
20. The vehicle charging method of claim 18, wherein the high-frequency switching element is a chip-type switch and has a control terminal and two connection terminals, the second capacitor being connected between one of the two connection terminals and one end of the first capacitor, and the other end of the first capacitor being connected to the other of the two connection terminals.