CN116118548B

CN116118548B - CP signal adaptation device and method for electric vehicle charging system

Info

Publication number: CN116118548B
Application number: CN202310092228.7A
Authority: CN
Inventors: 成瀚; 王臻; 梁新龙; 刘金文; 王会玖
Original assignee: Gongniu Group Co Ltd
Current assignee: Gongniu Group Co Ltd
Priority date: 2023-01-12
Filing date: 2023-01-12
Publication date: 2025-01-21
Anticipated expiration: 2043-01-12
Also published as: CN116118548A

Abstract

The present invention provides a CP signal adaptation device for an electric vehicle charging system, comprising: a sampling unit for acquiring a CP signal; a control unit for judging the working state of the electric vehicle charging system according to the CP signal transmitted from the sampling unit and generating a first control signal; an output unit for generating and outputting a new CP signal using the first control signal transmitted from the control unit. When the amplitude of the CP signal is within the working threshold range corresponding to the working state, the first control signal is used to dynamically modulate the amplitude of the new CP signal to make it reach the desired standard range. The present invention also provides a corresponding method.

Description

CP signal adapting device and method for electric automobile charging system

Technical Field

The invention relates to the field of electric automobiles, in particular to a CP signal adapting device and method for an electric automobile charging system.

Background

In recent years, with the development of the electric automobile industry, a charging system for an electric automobile is also widely used.

During charging of the vehicle by the charging system, the vehicle-side charging system needs to determine and adjust the operating state by judging whether or not the voltage of the control guidance function signal (CP signal) reaches a certain limit value, along with connection of the charging stake side and the vehicle-side charging system. However, in practical applications, since the electric vehicle models on the market are very wide, the production standards according to which are not exactly the same, and the performance of the charging system on the vehicle side may change after long-term use, the voltage amplitude of the CP signal detected on the vehicle side may not meet the limit value after the operation state is converted, so that normal charging is not possible.

The prior art provides for adapting the vehicle side by designing an additional dc power supply in the hardware circuit of the charging system to switch out two different CP signal voltage magnitudes. However, these methods require an additional voltage source to be configured for the charging pile side charging system, and have poor adjustment capability for CP signals and poor anti-interference capability, which severely limits the adaptation capability of the charging system and makes the charging process unstable.

Therefore, a new technology capable of dynamically adjusting the CP signal and having a strong anti-interference capability is needed to adapt the CP signal of the charging system of the electric vehicle.

Disclosure of Invention

The present invention is directed to overcoming the above and/or other problems in the art. The CP signal adapting device and the method for the electric automobile charging system can output accurate and stable CP signals, and are not easy to be influenced by interference, so that a stable charging process is realized.

According to one aspect of the present invention, there is provided a CP signal adaptation device for an electric vehicle charging system, the device including a sampling unit, a control unit, and an output unit. The sampling unit is used for acquiring the CP signal of the electric automobile charging system. And the control unit judges the working state of the electric vehicle charging system according to the CP signal transmitted from the sampling unit and generates a first control signal. The output unit generates and outputs a new CP signal using the first control signal transmitted from the control unit. And when the amplitude of the CP signal is in the range of the working threshold corresponding to the working state, the first control signal is used for dynamically modulating the amplitude of the new CP signal so as to enable the amplitude to reach the expected standard range.

According to a second aspect of the invention there is provided a CP signal adaptation method for an electric vehicle charging system comprising the steps of detecting the amplitude of a CP signal at a current time and determining therefrom the operating state of the electric vehicle charging system, comparing the amplitude of the CP signal with an operating threshold range of the gun state or charging state when the operating state is the gun state or charging state, modulating the amplitude of a new CP signal with a first control signal when the amplitude of the CP signal is within the operating threshold range, thereby dynamically modulating the amplitude to a desired standard value.

According to the CP signal adapting device and the CP signal adapting method, the amplitude of the current CP signal is detected and dynamically modulated to the corresponding standard value or the standard value close to the standard value according to the working state, so that even if the allowable amplitude range of the vehicle side is smaller, the obtained CP signal still can meet the allowable amplitude requirement of the smaller range. In addition, the dynamic mode is used for modulating the amplitude of the CP signal, so that the adaptation to all vehicle types can be achieved, and meanwhile, the dynamic modulation can also filter various interferences in the system, so that the stable and complete charging process is realized.

Preferably, in the CP signal adapting apparatus and method of the present invention, the first control signal may be generated by dynamically adjusting a duty cycle of a PWM waveform according to the operating state and the amplitude of the CP signal, so as to dynamically modulate the amplitude of a new CP signal. A PID algorithm may be used as the dynamic adjustment algorithm in the dynamic adjustment.

Preferably, when the amplitude of the CP signal exceeds the working threshold range corresponding to the working state, it may be determined that the charging system is in an abnormal state, and a corresponding processing procedure may be adopted for the abnormal state.

Preferably, the working states at least comprise an unconnected state, a gun inserting state and a charging state.

Preferably, the frequency of the first control signal may be 25kHz, so that the frequency of the first control signal is outside the range perceivable by the human ear and is easy to filter.

According to a third aspect of the present invention, there is also provided a computer-readable storage medium having instructions stored thereon which, when executed, implement a CP signal adaptation method according to the present invention as described above.

Drawings

The invention may be better understood by describing exemplary embodiments thereof in conjunction with the accompanying drawings, in which:

fig. 1 shows a block diagram of a CP signal adaptation device according to the present invention;

Fig. 2 shows an exemplary circuit diagram of a CP signal amplitude source generating circuit in an output unit of a CP signal adaptation device according to the present invention;

Fig. 3 shows an example circuit diagram of a CP signal generation circuit in an output unit of a CP signal adaptation device according to the present invention;

FIG. 4 shows a control and guidance circuit schematic diagram of an electric vehicle charging system according to charging mode 3 connection C in GB/T18487.1-2015, and

Fig. 5 shows a flowchart of a CP signal adaptation method for an electric vehicle charging system according to the present invention.

Detailed Description

The present application will be further described with reference to specific embodiments and drawings, in which more details are set forth in the following description in order to provide a thorough understanding of the present application, it will be apparent that the present application can be embodied in many other forms than described herein, and that those skilled in the art may make similar generalizations and deductions depending on the actual application without departing from the spirit of the present application, and therefore should not be taken as limiting the scope of the present application in terms of the contents of this specific embodiment.

Unless defined otherwise, technical or scientific terms used in the claims and specification should be given the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. The terms first, second and the like in the description and in the claims, are not used for any order, quantity or importance, but are used for distinguishing between different elements. The terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, is intended to mean that elements or items that are immediately preceding the word "comprising" or "comprising", are included in the word "comprising" or "comprising", and equivalents thereof, without excluding other elements or items.

According to an embodiment of the invention, a CP signal adaptation device for an electric vehicle charging system is provided.

Referring to fig. 1, a block diagram of a CP signal adaptation device 100 according to the present invention is schematically shown. The CP signal adaptation device 100 includes a sampling unit 110, a control unit 120, and an output unit 130. The sampling unit 110 is configured to sample the CP signal in the charging system, so as to obtain the amplitude of the current CP signal without affecting the CP signal, and transmit the same to the control unit 120. The control unit 120 determines the operating state of the charging system according to the current CP signal provided by the sampling unit 110, and accordingly generates a first control signal and transmits the first control signal to the output unit 130. The output unit 130 generates and outputs a new CP signal using the first control signal.

Specifically, the control unit 120 may estimate the current operating state of the charging system by combining the current CP signal amplitude with the previous operating state of the charging system, and determine, according to the current operating state of the charging system, an operating threshold range in which the CP signal amplitude should be located at this time. When the current CP signal amplitude is within the operating threshold range, which means that the current CP signal is normal, the control unit 120 generates a first control signal for dynamically modulating the amplitude of the new CP signal so that the amplitude of the new CP signal gradually reaches the desired standard range. In an embodiment, the desired standard range may be more stringent than the operating threshold range. In an embodiment, the desired standard range may also be a single standard value. It should be noted that, when referring to the amplitude of the CP signal herein, reference is made to the positive amplitude of the CP signal.

The working threshold range is used for judging whether the CP signal is in a normal working range corresponding to the working state, and the working threshold range can be set according to actual conditions. The desired standard range or standard value is a range of CP signal amplitude values that is desired to be achieved, and it is expected that the vehicle-side charging system must be able to pass the judgment of the CP signal in this range. For example, the standard range or standard value may be a nominal value or a range immediately adjacent to the nominal value corresponding to the operating state. In one embodiment, the operating threshold range may be, for example, within (9±1.8) V, or, for example, (9±1.5) V, in the gun insertion state, at which point the desired standard range may be, for example, within (9±0.2) V, or 9V. In one embodiment, the operating threshold range may be, for example, within (6±1.8) V, or, for example, (6±1.5) V, in a charged state, at which time the desired standard range may be, for example, within (6±0.2) V, or 6V.

During charging, the amplitude of the CP signal changes accordingly with the change of the operating state, and the charging pile side and the vehicle side determine whether the current operating state is normal by detecting the amplitude of the CP signal (for example, as shown in fig. 4 to be described later, the charging pile side detects the CP signal at the detection point 1 and the vehicle side detects the CP signal at the detection point 2).

In the prior art, in order to adjust the amplitude of the CP signal, it is often employed to provide two different amplitudes (e.g., two amplitudes differing from each other by 1V), and then to make the adjustment by switching between the two different amplitudes. This adjustment is very flexible and the amplitude of the adjusted CP signal is a fixed difference from the original CP signal, so that the amplitude of the CP signal cannot substantially reach the nominal value. In the CP signal adapting device, the amplitude of the CP signal can be gradually changed through dynamic modulation without being limited by the amplitude of the initial CP signal, so that the adaptation to all vehicle types can be realized at the same time. By means of dynamic modulation, the amplitude of the CP signal can be changed to a desired standard range or standard value, thereby ensuring that the vehicle-side judgment of the CP signal can always pass. Furthermore, due to the progressive nature of the dynamic modulation, the interference experienced by the CP signal during this period can also be filtered out well, which enables a more stable charging process.

Alternatively, the control unit 120 may generate the first control signal by dynamically adjusting the duty ratio of the PWM waveform according to the current operation state and the amplitude of the CP signal, which will be described in detail below. For example, the dynamic adjustment may be performed using a dynamic adjustment algorithm, so that the amplitude of the CP signal may be more conveniently dynamically modulated. The dynamic adjustment algorithm may be any dynamic adjustment algorithm known to those skilled in the art, such as a PID algorithm.

Optionally, when the current CP signal amplitude exceeds the operating threshold range corresponding to the operating state, which indicates that the current CP signal is abnormal, i.e. it may be determined that the charging system is in an abnormal state, the control unit 120 may respond according to an abnormal response logic (e.g. as specified in GB/T18487.1-2015). In one embodiment, for example, when the operating state is a charging state and the amplitude of the current CP signal is 3V, it may be determined that a CP short circuit abnormality occurs, an abnormal state is entered, at which time charging may be stopped, and modulation of the amplitude of the CP signal (i.e., outputting the first control signal of the full duty cycle) may be stopped.

Alternatively, the operating states may include at least an unconnected state, a gun-inserted state, and a charged state. In one embodiment according to GB/T18487.1-2015, the nominal value of the CP signal amplitude is 12V in the unconnected state (also referred to as state 1), 9V in the gun-inserted state (also referred to as connected state or state 2), and 6V in the charged state (also referred to as state 3).

Alternatively, the frequency of the first control signal may be 25kHz. Because the hearing range of a person is usually 20-20000 Hz, the use of a frequency of 25khz can avoid acoustic interference to the person. In addition, a frequency of 25kHz is also advantageous for the filtering process.

Turning now to fig. 2, fig. 2 shows an exemplary circuit diagram of a CP signal amplitude source generating circuit in an output unit of a CP signal adaptation device according to the present invention. The generated CP signal amplitude source can be used for directly replacing the 12V amplitude source in the prior art.

Referring to FIG. 2, the CP signal amplitude source generation circuit includes two inputs, a 12V power supply (i.e., an original 12V amplitude source) and an IO1_CP_Adj (i.e., a first control signal), and one output, CP_USE (i.e., a CP signal amplitude source generated via the circuit), where CP_Adj is used only to indicate a signal at the node where it is located and not to indicate an input or output. The amplitude of the CP+ USE can be controlled by the Ic1_CP_Adj through PWM, the principle is that PWM control of the Ic1_CP_Adj can cause corresponding switch to NMOS of Q1, so that the G pole level of Q2 generates corresponding high-low change, and accordingly the on-off of a 12V power supply and the CP+ Adj is realized, the on-off enables the CP+ Adj to generate a waveform with the amplitude of 12V and the same duty ratio as the Ic1_CP_Adj, and then the waveform with the high-low change at the CP+ Adj is converted into a level CP+ USE with stable voltage value through a pi-type filter circuit formed by C1, C2 and R3 to serve as a CP signal amplitude source. As mentioned above, it is readily understood that the voltage value will be in the range of 0-12V depending on the duty cycle of the first control signal. For example, if the duty cycle is 100% (full duty cycle), cp+_use=12v corresponds to the original 12V power supply, if the duty cycle is 70%, cp+_use=8.4v, and so on. Thus, the CP signal amplitude source generating circuit of the present invention may be used to modulate the CP signal amplitude source according to the first control signal.

With the modulated CP signal amplitude source, a new CP signal may be ultimately generated using a CP signal generation circuit as shown in fig. 3, where CP _use is from the CP signal amplitude source generation circuit described above, -12V power may be generated by inverting the 12V power, out_s is used to superimpose PWM waveforms in the CP signal as desired. The magnitude of the generated CP signal will have a trend corresponding to CP _ USE. By continuing the dynamic modulation in this manner, the CP signal amplitude may be gradually modulated to a desired standard range or standard value.

In one example of a CP signal amplitude source generating circuit, the capacitance and resistance values may be taken as c1=2.2 μf; c2=0.47 μf; r1=0.1Ω; r2=r4=r6=1kΩ, r3=10Ω, and r5=10kΩ. It should be noted that other designs are possible and are within the scope of the invention.

An example of application of the CP signal adaptation device of the present invention is next described with reference to fig. 4.

Fig. 4 is a schematic diagram of a control and guidance circuit of an electric vehicle charging system according to charging mode 3 connection mode C in GB/T18487.1-2015. As shown in fig. 4, the CP signal is transmitted on the lowest line in the figure. At detection point 1, the sampling unit samples the CP signal. When the amplitude of the CP signal changes from 12V to 9.8V, the control unit may determine that the system state is converted from the unconnected state to the gun inserting state. Although in theory the acceptable CP signal amplitude at the vehicle side in the gun inserted state may fluctuate 0.8V up and down at the nominal value of 9V, the vehicle side may determine that it is unsatisfactory (i.e., abnormal state) even when the CP signal amplitude is 9.8V due to problems of vehicle model and loss, etc., and further stop charging. Here, the desired standard range in the gun insertion state may be set to (9±0.1) V, and the vehicle side may be able to determine passage with respect to the CP signal amplitude within the standard range. The control unit may first determine that the current amplitude (9.8V) is within an operational threshold range (e.g., (9±1.5) V) of the gun state, and then output a first control signal that dynamically reduces the CP signal amplitude to within (9±0.1) V. Therefore, the amplitude of the CP signal can quickly approach to (9+/-0.1) V, and the vehicle side is ensured to judge that the CP signal meets the requirement of the gun inserting state.

In addition, in order to make the amplitude adjustable upper limit larger, the magnitude of the resistance R1 in fig. 4 can be reduced accordingly. In one embodiment, R1 may be set to 680 Ω.

According to the embodiment of the invention, a CP signal adaptation method for an electric automobile charging system is correspondingly provided.

Referring to fig. 5, a flow chart of a CP signal adaptation method 500 for an electric vehicle charging system according to the present invention is shown. Method 500 may include steps 510 through 540.

In step 510, the amplitude of the CP signal at the current time is detected, and thus the operating state of the electric vehicle charging system is determined.

In step 520, when the operating state is a gun state or a charge state, the magnitude of the CP signal is compared to an operating threshold range for the gun state or charge state. When the working state is other states, the first control signal with full duty ratio is output without modulating the amplitude of the CP signal.

In step 530, when the amplitude of the CP signal is within the operating threshold range, the amplitude of the new CP signal is modulated with the first control signal, thereby dynamically modulating the amplitude to a desired standard value. When the amplitude of the CP signal exceeds the working threshold range, the abnormal state is judged, the amplitude of the CP signal is not required to be modulated, and the first control signal with the full duty ratio is output.

Alternatively, the first control signal may be generated by dynamically adjusting the duty cycle of the PWM waveform according to the current operating state and the amplitude of the CP signal. For example, the dynamic adjustment may be performed using a dynamic adjustment algorithm, which may be any dynamic adjustment algorithm known to those skilled in the art, such as a PID algorithm.

Optionally, when the current CP signal amplitude exceeds the working threshold range corresponding to the working state, it may be determined that the charging system is in an abnormal state, and an abnormal response is performed.

Alternatively, the frequency of the first control signal may be 25kHz.

The above-described CP signal adaptation method 500 corresponds to a CP signal adaptation means according to the present invention. Many of the design concepts and details described above as being applicable to the CP signal adaptation device of the present invention are equally applicable to the CP signal adaptation method 500, and the same advantageous technical effects may be obtained, which are not described herein.

According to an embodiment of the present invention, there is also provided a computer-readable storage medium having recorded thereon encoded instructions that, when executed, implement the CP signal adaptation method for an electric vehicle charging system described above. The computer readable storage medium may include a hard disk drive, a floppy disk drive, a compact disk read/write (CD-R/W) drive, a Digital Versatile Disk (DVD) drive, a flash memory drive, and/or a solid state storage device, among others.

Various aspects of the invention are described above by way of some example embodiments. Nevertheless, it will be understood that various modifications may be made to the exemplary embodiments described above without departing from the spirit and scope of the invention. For example, if the described techniques are performed in a different order and/or if components in the described systems, architectures, devices or circuits are combined in a different manner and/or replaced or supplemented by additional components or equivalents thereof, suitable results may also be achieved, and accordingly, such other embodiments as modified fall within the scope of the claims.

Claims

1. A CP signal adaptation device for an electric vehicle charging system, comprising:

the sampling unit is used for acquiring the CP signal;

The control unit judges the working state of the electric vehicle charging system according to the CP signal transmitted from the sampling unit and generates a first control signal;

an output unit generating and outputting a new CP signal using the first control signal transmitted from the control unit,

And when the amplitude of the CP signal is in the range of the working threshold corresponding to the working state, the first control signal is used for dynamically modulating the amplitude of the new CP signal so as to enable the amplitude of the new CP signal to reach the expected standard range.

2. The CP signal adaptation apparatus of claim 1, wherein the control unit generates the first control signal by dynamically adjusting a duty cycle of a PWM waveform according to the operating state and the magnitude of the CP signal.

3. The CP signal adaptation device of claim 2, wherein a PID algorithm is used as the dynamic adjustment algorithm in the dynamic adjustment.

4. The CP signal adaptation apparatus of claim 1, wherein an abnormal state is determined when the magnitude of the CP signal exceeds an operating threshold range corresponding to the operating state.

5. The CP signal adapter device of claim 1, wherein the operational status comprises at least an unconnected status, a gun status, and a charged status.

6. CP signal adaptation means according to any of the claims 1-5, characterized in that the frequency of the first control signal is 25kHz.

7. A CP signal adaptation method for an electric vehicle charging system, comprising the steps of:

Detecting the amplitude of a CP signal at the current moment, and judging the working state of the electric vehicle charging system according to the amplitude;

comparing the amplitude of the CP signal with the working threshold range of the gun state or the charging state when the working state is the gun state or the charging state, and

When the amplitude of the CP signal is within the operating threshold range, the amplitude of the new CP signal is modulated with a first control signal, thereby dynamically modulating the amplitude to a desired standard value.

8. The CP signal adaptation method of claim 7, wherein the first control signal is generated by dynamically adjusting a duty cycle of a PWM waveform based on the operating state and the magnitude of the CP signal.

9. The CP signal adaptation method of claim 8, wherein a PID algorithm is used as the dynamic adjustment algorithm in the dynamic adjustment.

10. The CP signal adaptation method of claim 7, wherein an abnormal state is determined when the magnitude of the CP signal exceeds an operating threshold range corresponding to the operating state.

11. A CP signal adaptation method as claimed in any one of claims 7 to 10, wherein the frequency of said first control signal is 25kHz.

12. A computer readable storage medium having stored thereon instructions which, when executed, implement the method of any of claims 7 to 11.