CN110789393B

CN110789393B - Signal abnormality detection method, charging device, computer device, and storage medium

Info

Publication number: CN110789393B
Application number: CN201911022219.0A
Authority: CN
Inventors: 石宝辉
Original assignee: Hengda Smart Charging Technology Co ltd
Current assignee: Evergrande Hengchi New Energy Automobile Research Institute Shanghai Co Ltd
Priority date: 2019-10-25
Filing date: 2019-10-25
Publication date: 2021-01-15
Anticipated expiration: 2039-10-25
Also published as: CN110789393A

Abstract

The invention discloses a signal anomaly detection method for detecting a Pulse Width Modulation (PWM) signal, which comprises the following steps: detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal; determining the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal not to exceed a first rated value, determining the contact impedance of a charging gun according to a preset rule, and determining the sum of the capacitive reactance of a charging device, the capacitive reactance of a signal line and the capacitive reactance of an electric vehicle; and determining that the contact impedance of the charging gun is not in a first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is not in a second rated range, outputting first abnormal information, and monitoring signal abnormality in real time. The invention also provides a charging device, computer equipment and a storage medium.

Description

Signal abnormality detection method, charging device, computer device, and storage medium

Technical Field

The present invention relates to the field of signal detection, and in particular, to a signal abnormality detection method and a charging device, and a computer device and a storage medium based on the signal abnormality detection method.

Background

With the increasingly widespread use of charging automobiles, the industry chains of the charging automobiles at the upstream and the downstream are also developed vigorously at present, as an infrastructure link, the research and the development and the construction of charging piles gradually enter the visual field of people, and in order to better realize the efficient and rapid charging of the automobiles, the research on charging protocols is the most important.

At present, according to the market survey of charging piles, the charging piles are mainly divided into alternating current charging piles and direct current charging piles. Wherein alternating-current charging stake uses seven hole interfaces and three hole interfaces, and direct-current charging stake uses nine hole interfaces.

In the existing alternating current charging pile, power control is performed through a CP (control confirmation) signal, so that the signal quality of the CP signal is an important link for smooth communication. The CP signal is actually a Pulse Width Modulation (PWM) signal, and a scheme for monitoring the CP signal in real time and determining the communication reliability of the CP signal is lacking in the current charging pile.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a signal abnormity detection method, which realizes stable monitoring of signals and determines the reliability of the signals so as to ensure the stability of communication. The invention also provides a charging device, and computer equipment and a storage medium based on the signal abnormality detection method.

In order to realize the purpose, the following technical scheme is adopted:

in a first aspect, a signal anomaly detection method for detecting a Pulse Width Modulation (PWM) signal includes:

detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

determining the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal not to exceed a first rated value, determining the contact impedance of a charging gun according to a preset rule, and determining the sum of the capacitive reactance of a charging device, the capacitive reactance of a signal line and the capacitive reactance of an electric vehicle;

and determining that the contact impedance of the charging gun is not in a first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not in a second rated range, and outputting first abnormal information.

In a second aspect, a charging apparatus for detecting a PWM signal, the apparatus comprising:

the detection unit is used for detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

the processing unit is used for determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal do not exceed the first rated value, determining the contact impedance of the charging gun according to a preset rule, and determining the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile; and the number of the first and second groups,

and the signal output unit is used for determining that the contact impedance of the charging gun is not in the first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not in the second rated range, and outputting first abnormal information.

In a third aspect, a computer device comprises a processor and a memory, the processor being coupled to the memory and the processor executing instructions in operation to implement the signal anomaly detection method of the first aspect.

In a fourth aspect, a storage medium has a computer program stored thereon, the computer program being executed by a processor to implement the signal abnormality detection method of the first aspect.

The technical scheme of the invention has the following beneficial effects:

according to the invention, through monitoring the rising time and/or the falling time of the rising edge of the PWM signal, the contact impedance of the charging gun, the capacitance reactance of the charging device, the capacitance reactance of the signal line and the sum of the capacitance reactance of the electric automobile, whether the rising time and/or the falling time of the rising edge of the signal, the contact impedance of the charging gun, the capacitance reactance of the charging device, the capacitance reactance of the signal line and the sum of the capacitance reactance of the electric automobile are normal or not is further sequentially judged, if all the judgment results are normal, the signal is normal, no abnormal information is output, and real-time signal monitoring is realized.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, and it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope of the present invention.

Fig. 1 is a schematic structural diagram of a frame of a charging device and an electric vehicle charging connection according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of a signal anomaly detection method according to an embodiment of the present invention;

FIG. 3 is a schematic flow chart of a signal anomaly detection method according to another embodiment of the present invention;

FIG. 4 is a flowchart illustrating a method for detecting signal anomalies according to yet another embodiment of the present invention;

fig. 5 is a schematic structural diagram of a frame of a charging device according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a frame structure of a computer device according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a frame structure of a computer-readable storage medium according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive work based on the embodiments of the present invention, are within the scope of the present invention.

In order to make the objects, technical solutions and advantageous technical effects of the present invention more clearly and completely apparent, the technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Fig. 1 is a schematic circuit diagram of a charging connection between a charging device and an electric vehicle according to an embodiment of the present invention. As shown in fig. 1, the signal line transmission model circuit diagram of the present embodiment includes:

the model part of the circuit A is a charging pile CP (control confirmation) signal driving model, the model B is a CP transmission line model, and the model C is a charging automobile pile end model.

Further: in model A, U₁Serving as a voltage-stabilizing source for the drive source, R₂As internal resistance of driving source, a first capacitor C₁Is a capacitive reactance of a driving source, i.e. a capacitive reactance of a charging device, R₄The voltage dividing resistor is standardized for the national standard;

in model B, R₆Is equivalent resistance of signal line, first resistance R₁For charging gun contact impedance, a second capacitor C₂The capacitive reactance is equivalent capacitive reactance of a signal line, namely the capacitive reactance of the signal line;

in model C, R₃The voltage dividing resistor at the vehicle end (different values according to different charging states),third capacitor C₃Is a vehicle end capacitive reactance, R₅Is a vehicle-end diode equivalent resistance, C₄Is the equivalent capacitance of the vehicle-end diode.

Further, according to the practical application principle;

transmission line equivalent resistance R₆Is 0.001 ohm<<1000 ohms, so can be ignored;

equivalent capacitance C of diode₄Is 5pF<<1000pF, diode equivalent resistance R₅Can be ignored, therefore C₄The charge and discharge effect caused by the voltage difference between the two ends can be ignored.

According to a capacitor charging and discharging model:

T=τ*ln((V_H-V_L)/(V_H-V_T))；

t is the rising time of the rising edge and/or the falling time of the falling edge of the CP signal, and can be obtained through actual measurement; v_HIs the maximum voltage across the capacitor, V_LThe minimum voltage across the capacitor, since V is the maximum rise-fall delay of the CP signal_T=V_LTherefore T = τ; tau is a capacitance charging time constant and can be obtained by measuring the rising and falling time of a CP signal, and the calculation formula is as follows, wherein R is₄And R₃A first capacitor C of known parameters₁A second capacitor C₂A third capacitor C₃Can be obtained by national standard: τ = R = (R)₂+R₄+R₁+R₃)*(C₁+C₂+C₃)。

From the practical environment, the variable is only the first resistor R in the use process₁Contact resistance of charging gun by changing intensity of driving source₂A value of (2), the first resistance R can be measured₁And (C)₁+C₂+C₃) A value of (d); specifically, R is obtained by solving a system of linear equations of two-dimensional₁And (C)₁+C₂+C₃) In the equation,. tau.is obtained by actual measurement. And comparing the obtained value with an actual standard specification or a big data statistical reference value to judge whether the monitored parameter meets the specification requirement, and further determining whether the charging device is abnormal.

Referring to fig. 2, fig. 2 is a schematic flow chart of a signal anomaly detection method according to an embodiment of the present invention. A signal anomaly detection method for detecting a width modulated PWM signal, the method comprising:

step S10, detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

step S20, determining the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal not to exceed a first rated value, determining the contact impedance of the charging gun according to a preset rule, and determining the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile; and the number of the first and second groups,

step S30, if it is determined that the charging gun contact impedance is not within the first rated range, and/or the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is not within the second rated range, outputting first abnormality information.

The present embodiment describes a charging device as an example, when the charging device is connected to an electric vehicle, the charging device communicates with the electric vehicle by sending a PWM signal, and the charging device sends the PWM signal with different duty ratios to the electric vehicle according to different working states to represent different communication information, where the PWM signal is a pulse signal with periodically alternating peak values and valley values.

In step S10, the charging device detects the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, that is, the time during which the PWM signal rises from the bottom to the peak or falls from the peak to the bottom, and theoretically, when the state of charge is stable, the rising time of the rising edge of the PWM signal and the falling time of the falling edge are the same, and therefore, the detection or determination of the PWM signal may be performed only for the rising time of the rising edge or the falling time of the falling edge, or may be performed for both the rising time and the falling time.

In step S20, the rising time and/or the falling time of the detected rising edge is compared with the first rated value, and it can be understood that the first rated value is stored in the charging device in advance, when the rising time and/or the falling time of the rising edge of the PWM signal is detected, the two are compared, and accordingly a comparison result is obtained, wherein the comparison result includes that the rising time and/or the falling time of the rising edge of the PWM signal does not exceed the first rated value, and the rising time and/or the falling time of the falling edge of the PWM signal exceeds the first rated value. When the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are determined not to exceed the first rated value, it can be understood that the detected PWM signal is stable and can meet the communication requirement of the charging device and the electric vehicle, at the moment, the contact impedance of the charging gun is determined according to a preset rule, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined. It is understood that the charging device stores the preset rule in advance, and is specifically used for calculating the contact impedance of the charging gun according to the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, and determining the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle.

In step S30, the charging gun contact impedance, and the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance are compared with the corresponding rated ranges, respectively. Specifically, data of a first rated range and a second rated range are stored in the charging device in advance, in the step, whether the contact impedance of the charging gun meets the first rated range or not is judged through comparison, whether the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle meets the second rated range or not is judged through comparison, if the contact impedance of the charging gun is determined not to be in the first rated range, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined not to be in the second rated range, at least one condition occurs, namely, at least one parameter of the charging device is out of the rated range, the charging device is in an abnormal working state, the detected PWM signal is abnormal, and abnormal information is output correspondingly. It can be understood that, for the charging device outputting the abnormal information, the charging device may set to stop the charging operation in response to the abnormal information, or report the information to the charging system cloud or the charging user mobile terminal, etc.

In this embodiment, by monitoring the rising time and/or the falling time of the rising edge of the PWM signal, the contact impedance of the charging gun, the capacitance reactance of the charging device, the capacitance reactance of the signal line, and the sum of the capacitance reactance of the electric vehicle, and further determining whether the rising time and/or the falling time of the rising edge of the signal, the contact impedance of the charging gun, the sum of the capacitance reactance of the charging device, the capacitance reactance of the signal line, and the capacitance reactance of the electric vehicle satisfy the normal range, if the determination is within the normal range, it indicates that the detected PWM signal is normal, and it is not necessary to output abnormal information, thereby implementing real-time signal monitoring.

Further, the first nominal value comprises 2 μ β. In this embodiment, according to the charging-related standard of the electric vehicle, the first credit is set to 2 μ s, that is, the normal range of the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal is not more than 2 μ s. It will be appreciated that, depending on the actual situation, the first nominal value may be further set to other values, for example, 1.6 μ s, which may require a higher stability of the PWM signal output by the charging device, and accordingly, the charging device may be configured to output a more stable signal during the charging control process, further ensuring the system stability.

Further, the first nominal range comprises less than 15m Ω, in particular the first nominal range is determined according to charging related standard requirements. It is understood that the first nominal range may also be set to other ranges, such as less than 12m Ω.

Further, the second rated range comprises 300-5500 pF. Specifically, the second rated range is determined by performing big data statistics on the charging parameters of the charging device in normal operation. Preferably, in order to enable the charging parameter of the charging device to be in a more stable range and ensure that the charging device outputs a more stable PWM signal, the second rated range may be further set to be 1500-5500 pF.

Further, driving the internal resistance R of the cell₂Adjusting R according to different driving types and the resistance value of 1-100 omega₂For different resistances, the actual output is regulated to different drivesDynamic strength.

Referring to fig. 3, in step S10, the method further includes detecting a rising time of a rising edge and/or a falling time of a falling edge of the PWM signal, and then:

step S40, if it is determined that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal exceeds the first rated value, increasing the driving strength of the PWM signal, and re-executing the step S10, detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

in step S20, if it is determined that the rising time of the rising edge and/or the falling time of the falling edge of the re-detected PWM signal does not exceed the first rated value, re-determining a new contact impedance of the charging gun according to the preset rule, and re-determining a sum of a new capacitive reactance of the charging device, a new capacitive reactance of the signal line, and a new capacitive reactance of the electric vehicle; and the number of the first and second groups,

in the step S30, if it is determined that the contact impedance of the charging gun is not within the first rated range, and/or the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle is not within the second rated range, outputting first abnormal information; or, in step S50, the charging gun contact impedance is determined to be within the first rated range, and the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is determined to be within the second rated range, and the above-described re-detection operation is repeated.

In this embodiment, when the PWM signal is initially detected and the rising time of the rising edge and/or the falling time of the falling edge of the detected PWM signal is compared with the rated value, and the PWM signal is not normally outputted initially if the PWM signal does not satisfy the set rated range, the charging device controls the driving source to increase the driving strength so that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal is changed by changing the driving strength while the charging device is kept in the current connection state, and further, the above steps S10 to S30 are re-executed. Therefore, the charging device is detected by the detection method, the charging parameters of the charging device can be ensured to be in a normal state in the initial stage, and the accuracy of detecting the abnormity of the charging device is improved; and after the driving strength is improved, in the re-detection and verification of the PWM signal, when the PWM signal is determined to be normal, the re-detection action is repeated, actually, the normality of all parameters of the PWM signal is circularly detected, and the real-time monitoring of the PWM signal is realized.

Specifically, when the rising time of the rising edge and/or the falling time of the falling edge of the signal exceeds the first rated value, the output pulse signal is unstable, and deviates from the characteristic that the pulse signal is periodically and rapidly output alternately between the peak value and the valley value, therefore, in the present embodiment, the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal does not exceed the first rated value, which is used as a condition for judging that the PWM signal is normal. Further, the driving strength of the PWM signal is improved by actually reducing the internal resistance of the PWM signal driving source.

Further, in step S20, if it is determined that the rising time of the rising edge and/or the falling time of the falling edge of the re-detected PWM signal does not exceed the first rated value, the charging gun contact impedance is determined according to a preset rule, and the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is determined, and then the method further includes:

step S60, determining that the charging gun contact impedance is within the first rated range; if the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined to be within the second rated range, continuously detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal; and the number of the first and second groups,

and step S70, determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal deviate, and outputting second abnormal information.

In this embodiment, when the charging pile is connected normally, the charging gun contact resistance R₁And charging device capacitive reactance C₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Is in a steady state according to T = τ = R = (R = C =)₂+R₄+R₁+R₃)*(C₁+C₂+C₃) It can be understood that when the charging gun contacts the resistance R₁And charging device capacitive reactance C₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃) Stable internal resistance R of driving source of charging device₂Stable, voltage dividing resistor R for electric automobile₃Stable, charging device divider resistance R₄And (4) stabilizing. Accordingly, the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal are also in a steady state. It can be understood that, in the operating state of the charging device, the driving source of the charging device is stable, the electric vehicle side is stable, and the most general problem that may occur is that the charging gun is loosened. Theoretically, when the charging gun is in the initial connection state, the charging gun contacts the impedance R₁Very small, signal line capacitive reactance C₂Zero, when the charging gun becomes loose, the connection between the charging device end and the vehicle end changes, wherein the contact resistance R of the charging gun changes₁And signal line capacitive reactance C₂Both become larger, and according to the above formula, the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal become larger accordingly. Therefore, in this embodiment, on the basis of the foregoing implementation steps, the continuous monitoring of the charging device is configured to monitor the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal, and determine whether the detected rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal are deviated to reflect the corresponding abnormal state.

Specifically, in the step S60, on the basis of the foregoing embodiment, when the contact impedance of the charging gun is determined, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle is determined to be within the corresponding rated range, that is, the charging parameters are in the normal state when the charging device is in the current state, it can be understood that, in the subsequent monitoring of the PWM signal of the charging device, the PWM signal and the corresponding plurality of charging parameters are no longer monitored at the same time, but only the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are detected, and whether the deviation occurs is determined. It can be understood that, in the foregoing steps of the embodiment, the rising time and/or the falling time of the falling edge of the initial PW signal is detected to satisfy the normal charging state, and the charging gun contact impedance determined according to the rising time and/or the falling time of the rising edge of the PWM signal is detected to determine the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance, and also satisfy the normal charging state, at this time, the detection of the rising time and/or the falling time of the falling edge of the PWM signal is not repeated, the detection of the charging gun contact impedance is detected, and the detection of whether the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is normal is performed, but only the detection of the rising time and/or the falling time of the falling edge of the subsequent PWM signal is performed, and the comparison is performed to determine whether the rising time and/or the falling time of the falling edge of the PWM signal is deviated from the rising time and/or the falling time of the, if the deviation of the rising time of the rising edge and/or the falling time of the falling edge is found in the process of continuously detecting the PWM signal, namely the PWM signal of the charging device is abnormal, the charging state is abnormal, and accordingly, an abnormal signal is output according to the abnormal condition. It can be understood that, for the charging device outputting the abnormal information, the charging device may set to stop the charging operation in response to the abnormal information, or report the information to the charging system cloud or the charging user mobile terminal, etc.

Referring to fig. 4, in a further embodiment, in the step S60, the continuously detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal includes: detecting the rising time of the rising edge and the falling time of the falling edge of each PWM signal; in step S70, if it is determined that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal deviate, outputting second abnormal information, which specifically includes: and determining that the value of the rise time and/or the fall time of the rise edge of one PWM signal, which is increased from the rise time or the fall time obtained by last detection, exceeds a preset time value, and outputting second abnormal information.

In this embodiment, the rising time of the rising edge and the falling time of the falling edge of each PWM signal are detected, and it is determined that the deviation occurs when the rising time or the falling time of one of the PWM signals is greater than the preset time value that is exceeded in the previous PWM signal. For example, the preset time value is set to 0.5 μ S, the rise time or fall time detected according to step S10 is 0.8 μ S, the rise time Tr1 of the first rising edge of the subsequent continuous detection PWM signal is 0.85 μ S, the fall time Tf1 of the first falling edge is 0.85 μ S, the rise time Tr2 of the second rising edge is 0.9 μ S, the fall time Tf2 of the second falling edge is 0.85 μ S, and the rise time Tr3 of the third rising edge is 1.5 μ S, where the difference of Tr3 greater than Tf2 is 0.65 μ S and exceeds the preset time value by 0.5 μ S, at which time the aforementioned abnormality determination condition is satisfied, the charging state of the charging device is determined to be abnormal, and the second abnormality information is output.

It will be appreciated that in another embodiment, anomalies may also be detected as follows: and detecting the rising time and/or the falling time of the falling edge of the PWM signal every preset time, determining that the value of the rising time and/or the falling time of the rising edge of the PWM signal at one time is larger than the value of the preset time compared with the rising time or the falling time obtained by last detection, and outputting second abnormal information. In this embodiment, the interval preset time is set to detect the PWM signal, and therefore, the detected result may include only the rising time or the falling time, or both the rising time and the falling time. For example, the preset time is set to 0.5ms, that is, the rising time of the rising edge or the falling time of the falling edge of the PWM signal is detected once every 0.5ms, the preset time value is set to 0.5 μ S, specifically, the rising time or the falling time detected according to step S10 is 0.8 μ S, the PWM signal is detected once at a subsequent interval of 0.5ms, the first time is the rising time T1, specifically, 0.85 μ S, the second time is the falling time T2, specifically, 0.85 μ S, the third time is the falling time T3, specifically, 0.9 μ S, the fourth time is the falling time T4, specifically, 0.85 μ S, the fifth time is the rising time T5, specifically, 1.5 μ S, at which the foregoing abnormality determination condition is satisfied, the fifth time T5 is greater than the fourth time T4 and exceeds 0.5 μ S, the charging state abnormality of the charging device is determined, and the second abnormality information is output.

It will be appreciated that in another embodiment, anomalies may also be detected as follows: and detecting the rising time of the rising edge and the falling time of the falling edge of each PWM signal, determining that the rising time and/or the falling time of the falling edges of a plurality of PWM signals are/is increased in sequence, and outputting second abnormal information. In this embodiment, four are taken as an example for description, that is, it is determined that a deviation occurs when the rising time and the falling time are continuously increased to four. It can be understood that this is actually a deviation trend, and in this embodiment, setting such a deviation trend as a deviation determination condition is beneficial to more accurately detecting the abnormality of the charging device, and avoiding the situation that the abnormality occurs but the detection is not timely. Specific examples are: a plurality of four are provided, the rising time or falling time detected according to the step S10 is 0.8 μ S, the rising time Tr1 of the first rising edge of the subsequent continuous detection PWM signal is 0.85 μ S, the falling time Tf1 of the first falling edge is 0.85 μ S, the rising time Tr2 of the second rising edge is 0.9 μ S, the falling time Tf2 of the second falling edge is 0.85 μ S, the rising time Tr3 of the third rising edge is 1.0 μ S, the falling time Tf3 of the third falling edge is 1.05 μ S, and the rising time Tr4 of the fourth rising edge is 1.2 μ S, where up to four of time values are sequentially added, specifically Tf2, Tr3, Tf3, and Tr4, at which the foregoing abnormality determination condition is satisfied, the charging state of the charging device is determined to be abnormal, and second abnormality information is output.

It will be appreciated that in another embodiment, anomalies may also be detected as follows: and detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal at each preset interval, determining that the rising time and/or the falling time of the falling edge of a plurality of PWM signals are increased in sequence, and outputting second abnormal information. In the embodiment, four are taken as an example for description, that is, it is determined that a deviation occurs when the rising time and the falling time are continuously increased to four; the preset time is set to 0.5ms, i.e., the rising time of the rising edge or the falling time of the falling edge of the PWM signal is detected every 0.5 ms. Specific examples are: setting four of the plurality, detecting the rising time or the falling time of 0.8 μ S according to the step S10, detecting the PWM signal once at a subsequent interval of 0.5ms, specifically, for example, the first time is the rising time T1, specifically, the time is 0.85 μ S, the second time is the falling time T2, specifically, the time is 0.85 μ S, the third time is the falling time T3, specifically, the time is 0.9 μ S, the fourth time is the falling time T4, specifically, the time is 0.85 μ S, the fifth time is the rising time T5, specifically, the time is 1.0 μ S, the sixth time is the falling time T6, specifically, the time is 1.05 μ S, the seventh time is the rising time T7, specifically, the time is 1.2 μ S, wherein the values of the time are sequentially increased by four, specifically, T4, T5, T6 and T7, at this time, the foregoing abnormality determination condition is satisfied, determining the abnormal charging state of the charging apparatus is abnormal, and outputting the second abnormal information.

Further, in step S20, according to a preset rule, determining a contact impedance of the charging gun, and determining a sum of a capacitive reactance of the charging device, a capacitive reactance of the signal line, and a capacitive reactance of the electric vehicle, specifically includes:

adjusting internal resistance R of PWM signal driving source₂Detecting the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal at different driving strengths, and calculating the contact resistance R of the charging gun according to the following formula₁And calculating the capacitive reactance C of the charging device₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃)：T=τ*ln((V_H-V_L)/(V_H-V_T))，τ=R*C=(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) (ii) a Wherein, V_HFor maximum voltage across the PWM drive source capacitor, V_LIs the minimum voltage, V, across the PWM drive source capacitor_TThe voltage at two ends of a capacitor of a PWM driving source at T moment, tau is a capacitor charging time constant, R₃Is a voltage-dividing resistor of an electric automobile, R₄The voltage dividing resistor is used for the charging device.

In this example, T = τ × ln ((V)_H-V_L)/(V_H-V_T))，V_HIs the maximum voltage across the capacitor, V_LIs the minimum voltage across the capacitor, V_TThe maximum rising edge or falling delay of PWM signal is the capacitor voltage, then V_T=V_LTherefore, T = τ. According to the relationship between the rising time of the rising edge and/or the falling time of the falling edge, the contact resistance of the charging gun, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle, the formula T = tau = R C = (R = tau = R =)₂+R₄+R₁+R₃)*(C₁+C₂+C₃) Adjusting internal resistance R of PWM signal driving source₂Obtaining two groups of charging data: t = τ = R = (R) =₂+R₄+R₁+R₃)*(C₁+C₂+C₃)，T’=(R₂’+R₄+R₁+R₃)*(C₁+C₂+C₃) And then (C) is obtained₁+C₂+C₃)=(T’-T)/(R₂’-R₂)，R1=T(R₂’-R₂)/(T’-T)-R₂-R₃-R₄。

Further, at the step, the charging gun contact resistance R is calculated according to the following formula₁And charging device capacitive reactance C₁Capacitive reactance C of electric automobile₂And signal line capacitive reactance C₃The sum of (a) and (b): t = τ ln ((V)_H-V_L)/(V_H-V_T))，τ=R*C=(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) And then, further comprising: adjusting and recovering internal resistance R of PWM signal driving source₂。

In this embodiment, on the basis of the foregoing embodiment, the internal resistance of the driving source of the charging device is adjusted, the contact impedance of the charging gun is calculated and determined, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle is calculated and determined.

Preferably, the internal resistance R of the PWM signal driving source is adjusted₂The method specifically comprises the following steps: adjusting internal resistance R of the PWM signal driving source₂Increased resistance value of not less than 30 omega。

Further, the first abnormality information includes contact abnormality information and capacitive load abnormality information. It can be understood that when the contact impedance of the charging gun is detected not to meet the normal range, the contact abnormal information is correspondingly output; and when the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is detected not to meet the normal range, outputting the capacitive load abnormal information.

Referring to fig. 5, an embodiment of the present invention further provides a charging apparatus 100 for detecting a PWM signal, the apparatus including:

a detection unit 10 for detecting a rising time of a rising edge and/or a falling time of a falling edge of the PWM signal;

the processing unit 20 is configured to determine that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal does not exceed a first rated value, determine a contact impedance of the charging gun according to a preset rule, and determine a sum of a capacitive reactance of the charging device, a capacitive reactance of the signal line, and a capacitive reactance of the electric vehicle; and the number of the first and second groups,

and the signal output unit 30 is used for determining that the contact impedance of the charging gun is not in the first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not in the second rated range, and then outputting first abnormal information.

The detection unit 10 detects the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, that is, the time during which the PWM signal rises from the bottom to the peak or falls from the peak to the bottom, and theoretically, when the state of charge is kept stable, the rising time of the rising edge of the PWM signal and the falling time of the falling edge are the same, and therefore, the detection or determination of the PWM signal may be performed only for the rising time of the rising edge or the falling time of the falling edge, or may be performed for both the rising time and the falling time.

The processing unit 20 compares and determines the rising time and/or the falling time of the detected rising edge with a first rated value, and it can be understood that the first rated value is stored in the processing unit 20 in advance, when the rising time and/or the falling time of the detected falling edge of the PWM signal are detected, the rising time and/or the falling time of the detected falling edge of the PWM signal are compared, and a comparison result is obtained accordingly, wherein the comparison result includes that the rising time and/or the falling time of the detected rising edge of the PWM signal do not exceed the first rated value, and the rising time and/or the falling time of the detected falling edge of the PWM signal exceed the first rated value. When the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are determined not to exceed the first rated value, it can be understood that the detected PWM signal is stable and can meet the communication requirement of the charging device and the electric vehicle, at the moment, the contact impedance of the charging gun is determined according to a preset rule, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined. It is understood that the charging device stores the preset rule in advance, and is specifically used for calculating the contact impedance of the charging gun according to the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, and determining the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle.

The signal output unit 30 compares the charging gun contact impedance, the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance with the corresponding rated range. Specifically, data of a first rated range and a second rated range are stored in the charging device in advance, in the step, whether the contact impedance of the charging gun meets the first rated range or not is judged through comparison, whether the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle meets the second rated range or not is judged through comparison, if the contact impedance of the charging gun is determined not to be in the first rated range, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined not to be in the second rated range, at least one condition occurs, namely, at least one parameter of the charging device is out of the rated range, the charging device is in an abnormal working state, the detected PWM signal is abnormal, and abnormal information is output correspondingly. It can be understood that, for the charging device outputting the abnormal information, the charging device may set to stop the charging operation in response to the abnormal information, or report the information to the charging system cloud or the charging user mobile terminal, etc.

Further, driving the internal resistance R of the cell₂Adjusting R according to different driving types and the resistance value of 1-100 omega₂The different driving strengths are actually adjusted and output for different resistance values.

Further, the charging device 100 further includes a signal driving unit 40, where the signal driving unit 40 is configured to determine that a rising time of a rising edge and/or a falling time of a falling edge of the PWM signal exceeds the first rated value, and then increase the driving strength of the PWM signal; the detection unit is further used for re-detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal; the processing unit is further configured to determine that the rising time of the rising edge and/or the falling time of the falling edge of the re-detected PWM signal does not exceed a first rated value, and then re-determine a new contact impedance of the charging gun according to the preset rule, and re-determine a sum of a new capacitive reactance of the charging device, a new signal line capacitive reactance, and a new capacitive reactance of the electric vehicle; the signal output unit is further used for determining that the contact impedance of the charging gun is not within the first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not within the second rated range, and outputting first abnormal information; or determining that the contact impedance of the charging gun is within the first rated range, determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is within the second rated range, and sending a command of re-detection to the detection unit.

In this embodiment, after the driving strength of the PWM signal is increased, the signal driving unit 40 sends a control instruction to the detecting unit 10, the detecting unit 10 receives the control instruction to detect the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal again, and further, the processing unit 20 and the signal output unit 30 sequentially execute the detection operation.

In this embodiment, when the PWM signal is initially detected and the rising time of the rising edge and/or the falling time of the falling edge of the detected PWM signal is compared with the rated value, and the PWM signal is not normally outputted initially if the PWM signal does not satisfy the set rated range, the charging device controls the driving source to increase the driving strength so that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal is changed by changing the driving strength while the charging device is kept in the current connection state, and further, the above steps S10 to S30 are re-executed. Therefore, the charging device is detected by the detection method, the charging parameters of the charging device are ensured to be in a normal state in the initial stage, and the accuracy of detecting the abnormity of the charging device is improved.

Further, the signal driving unit 40 is specifically configured to determine that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal exceeds the first rated value, and then decrease the internal resistance of the PWM signal driving source.

The detection unit 10 is further used for determining that the contact impedance of the charging gun is in a first rated range; if the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is determined to be within a second rated range, the contact impedance of the charging gun is continuously detected; the signal output unit 30 is further configured to determine that the contact impedance of the charging gun is deviated, and output second abnormal information.

In this embodiment, when the charging pile is connected normally, the charging gun contact resistance R₁And charging device capacitive reactance C₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Is in a steady state according to T = τ = R = (R = C =)₂+R₄+R₁+R₃)*(C₁+C₂+C₃) It can be understood that when the charging gun contacts the resistance R₁And charging device capacitive reactance C₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃) Stable internal resistance R of driving source of charging device₂Stable, voltage dividing resistor R for electric automobile₃Stable, charging device voltage divisionResistance R₄And (4) stabilizing. Accordingly, the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal are also in a steady state. It can be understood that, in the operating state of the charging device, the driving source of the charging device is stable, the electric vehicle side is stable, and the most general problem that may occur is that the charging gun is loosened. Specifically, when the charging gun is in the initial connection state, theoretically, the charging gun contacts the resistance R₁Very small, signal line capacitive reactance C₂Zero, when the charging gun becomes loose, the connection between the charging device end and the vehicle end changes, wherein the contact resistance R of the charging gun changes₁And signal line capacitive reactance C₂Becomes larger, and accordingly, the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal are/is increased according to the above formula. Therefore, in this embodiment, on the basis of the foregoing implementation steps, the continuous monitoring of the charging device is configured to monitor the rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal, and determine whether the detected rising time of the rising edge and/or the falling time T of the falling edge of the PWM signal are deviated to reflect the corresponding abnormal state.

Specifically, on the basis of the foregoing embodiment, when the contact impedance of the charging gun is determined, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line, and the capacitive reactance of the electric vehicle is determined to be within the corresponding rated range, that is, the charging device is in the current state, and each charging parameter is in the normal state, it can be understood that, in the subsequent monitoring of the PWM signal of the charging device, the PWM signal and the corresponding plurality of charging parameters are no longer monitored at the same time, but only the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are detected, and whether the deviation occurs is determined. It can be understood that, in the foregoing steps of the embodiment, the rising time and/or the falling time of the falling edge of the initial PW signal is detected to satisfy the normal charging state, and the charging gun contact impedance determined according to the rising time and/or the falling time of the rising edge of the PWM signal is detected to determine the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance, and also satisfy the normal charging state, at this time, the detection of the rising time and/or the falling time of the falling edge of the PWM signal is not repeated, the detection of the charging gun contact impedance is detected, and the detection of whether the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is normal is performed, but only the detection of the rising time and/or the falling time of the falling edge of the subsequent PWM signal is performed, and the comparison is performed to determine whether the rising time and/or the falling time of the falling edge of the PWM signal is deviated from the rising time and/or the falling time of the, if the deviation of the rising time of the rising edge and/or the falling time of the falling edge is found in the process of continuously detecting the PWM signal, namely the PWM signal of the charging device is abnormal, the charging state is abnormal, and accordingly, an abnormal signal is output according to the abnormal condition. It can be understood that, for the charging device outputting the abnormal information, the charging device may set to stop the charging operation in response to the abnormal information, or report the information to the charging system cloud or the charging user mobile terminal, etc.

Further, the detecting unit 10 is specifically configured to detect a rising time of a rising edge and a falling time of a falling edge of each PWM signal; or detecting the rising time of the rising edge of the PWM signal every preset time and/or the falling time of the falling edge; and the number of the first and second groups,

the signal output unit 30 is specifically configured to determine that a rise time of a rising edge and/or a fall time increase of a falling edge of two adjacent PWM signals exceeds a preset time value as a deviation, and output second abnormal information; or determining that the rising time of the rising edge and/or the falling time of the falling edge of a plurality of PWM signals are/is increased in sequence to generate deviation, and outputting second abnormal information.

It can be understood that the detection unit 10 and the signal output unit 30 specifically include four embodiments, which are specifically exemplified as follows.

In one embodiment, the rising time of the rising edge and the falling time of the falling edge of each PWM signal are detected, the deviation is determined when the rising time of the rising edge and/or the falling time of the falling edge of one PWM signal is larger than the preset time value than the last increase, and second abnormal information is output. In this embodiment, the rising time of the rising edge and the falling time of the falling edge of each PWM signal are detected, and it is determined that the deviation occurs when the rising time or the falling time of one of the PWM signals is greater than the preset time value that is exceeded in the previous PWM signal. For example, the preset time value is set to 0.5 μ s, the rising time or falling time of the first detection by the detection unit 10 is 0.8 μ s, the rising time Tr1 of the first rising edge of the subsequent continuous detection PWM signal is 0.85 μ s, the falling time Tf1 of the first falling edge is 0.85 μ s, the rising time Tr2 of the second rising edge is 0.9 μ s, the falling time Tf2 of the second falling edge is 0.85 μ s, and the rising time Tr3 of the third rising edge is 1.5 μ s, where the difference of Tr3 greater than Tf2 is 0.65 μ s and exceeds the preset time value by 0.5 μ s, at which time the foregoing abnormality determination condition is satisfied, the charging state of the charging device is determined to be abnormal, and the second abnormality information is output.

It is understood that in another embodiment, the following may also be used: the detecting unit 10 detects a rising time of a rising edge and/or a falling time of a falling edge of the PWM signal every a preset time, and the signal output unit 30 determines that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal of one time is deviated from the last increase by more than a preset time value, and outputs second abnormality information. For example, the preset time is set to 0.5ms, that is, the rising time or the falling time of the rising edge or the falling edge of the PWM signal is detected once every 0.5ms, the preset time value is set to 0.5 μ s, specifically, the PWM signal is detected once at a subsequent interval of 0.5ms according to the rising time or the falling time of the first detection by the detection unit 10 of 0.8 μ s, the rising time Tr1 of the first rising edge is 0.85 μ s, the falling time Tf1 of the first falling edge is 0.85 μ s, the rising time Tr2 of the second rising edge is 0.9 μ s, the falling time Tf2 of the second falling edge is 0.85 μ s, and the rising time Tr3 of the third rising edge is 1.5 μ s, at which the aforementioned abnormality determination condition is satisfied, it is determined that the charging state of the charging device is abnormal, and the second abnormality information is output.

It is understood that in another embodiment, the following may also be used: the detection unit 10 detects the rising time of the rising edge and the falling time of the falling edge of each PWM signal, and the signal output unit 30 determines that the rising times and/or the falling times of the rising edges of a plurality of PWM signals are sequentially increased to generate a deviation, and outputs second abnormal information. In this embodiment, four are taken as an example for description, that is, it is determined that a deviation occurs when the rising time and the falling time are continuously increased to four. It can be understood that this is actually a deviation trend, and in this embodiment, setting such a deviation trend as a deviation determination condition is beneficial to more accurately detecting the abnormality of the charging device, and avoiding the situation that the abnormality occurs but the detection is not timely. Specific examples are: four, the rising time or the falling time of the first detection by the detection unit 10 is 0.8 μ s, the rising time Tr1 of the first rising edge of the subsequent continuous detection PWM signal is 0.85 μ s, the falling time Tf1 of the first falling edge is 0.85 μ s, the rising time Tr2 of the second rising edge is 0.9 μ s, the falling time Tf2 of the second falling edge is 0.85 μ s, the rising time Tr3 of the third rising edge is 1.0 μ s, the falling time Tf3 of the third falling edge is 1.05 μ s, and the rising time Tr4 of the fourth rising edge is 1.2 μ s, where the four values of the time values are sequentially increased, specifically Tf2, Tr3, Tf3, and Tr4 are set, at which the aforementioned abnormality determination condition is satisfied, the charging state of the charging device is determined to be abnormal, and second abnormality information is output.

It will be appreciated that in another embodiment, anomalies may also be detected as follows: and detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal at each preset interval, determining that the rising time and/or the falling time of the falling edge of a plurality of PWM signals are increased in sequence to generate deviation, and outputting second abnormal information. In the embodiment, four are taken as an example for description, that is, it is determined that a deviation occurs when the rising time and the falling time are continuously increased to four; the preset time is set to 0.5ms, i.e., the rising time of the rising edge or the falling time of the falling edge of the PWM signal is detected every 0.5 ms. Specific examples are: four of the plurality of sensors are provided, and the PWM signal is detected once at a subsequent interval of 0.5ms according to the rise time or fall time detected by the detection unit 10 of 0.8 μ s, specifically, for example, the rise time Tr1 of the first rise edge is 0.85 μ s, the fall time Tf1 of the first fall edge is 0.85 μ s, the rise time Tr2 of the second rise edge is 0.9 μ s, the fall time Tf2 of the second fall edge is 0.85 μ s, the rise time Tr3 of the third rise edge is 1.0 μ s, the fall time Tf3 of the third fall edge is 1.05 μ s, and the rise time Tr4 of the fourth rise edge is 1.2 μ s, where up to four values of time values are sequentially added, specifically Tf2, Tr3, Tf3 and Tr4, at which the aforementioned abnormality determination condition is satisfied, the charging state of the charging device is determined to be abnormal, and second abnormality information is output.

Further, the charging device 100 further comprises a signal driving unit 40, wherein the signal driving unit 40 is used for adjusting the internal resistance R of the PWM signal driving source₂(ii) a The detecting unit 10 is further configured to detect a rising time of a rising edge and/or a falling time T of a falling edge of the PWM signal at different driving strengths, and the processing unit 20 is further configured to calculate a charging gun contact resistance R according to the following formula₁And calculating the capacitive reactance C of the charging device₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃)：T=τ*ln((V_H-V_L)/(V_H-V_T))，τ=R*C=(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) (ii) a Wherein, V_HFor maximum voltage across the PWM drive source capacitor, V_LIs the minimum voltage, V, across the PWM drive source capacitor_TThe voltage at two ends of a capacitor of a PWM driving source at T moment, tau is a capacitor charging time constant, R₃Is a voltage-dividing resistor of an electric automobile, R₄The voltage dividing resistor is used for the charging device.

In this example, T = τ × ln ((V)_H-V_L)/(V_H-V_T))，V_HIs the maximum voltage across the capacitor, V_LIs the minimum voltage across the capacitor, V_TThe maximum rising edge or falling delay of PWM signal is the capacitor voltage, then V_T=V_LTherefore, T = τ. According to the rising time of the rising edge and/or the falling time of the falling edge, the contact resistance of the charging gun, and the capacity of the charging deviceThe relation between the sum of the reactance, the signal line capacitive reactance and the capacitive reactance of the electric vehicle is specifically represented by the formula T = τ = R = (R =)₂+R₄+R₁+R₃)*(C₁+C₂+C₃) Adjusting internal resistance R of PWM signal driving source₂Obtaining two groups of charging data: t = τ = R = (R) =₂+R₄+R₁+R₃)*(C₁+C₂+C₃)，T’=(R₂’+R₄+R₁+R₃)*(C₁+C₂+C₃) And then (C) is obtained₁+C₂+C₃)=(T’-T)/(R₂’-R₂)，R1=T(R₂’-R₂)/(T’-T)-R₂-R₃-R₄。

Further, the signal driving unit 40 is also used for adjusting and restoring the internal resistance R of the PWM signal driving source₂。

Preferably, the internal resistance R of the PWM signal driving source is adjusted₂The method specifically comprises the following steps: adjusting internal resistance R of the PWM signal driving source₂The increased resistance value is not less than 30 Ω.

The invention provides a plurality of specific embodiments, which are implemented according to the scheme, and relevant parameters are calculated by adjusting the internal resistance of the driving source, so that corresponding detection judgment is carried out. Specific examples are as follows.

The first embodiment is as follows: measuring a 12V PWM (PWM charging mode is to charge the battery by pulse current with automatically changed duty ratio) specific signal: adjusting internal resistance R of signal driving unit ₂50 omega, the rise-fall time is 1.23 us; adjusting internal resistance of driving source to R ₂30 omega, the rising time of the rising edge and/or the falling time of the falling edge is 1.19us, and C is calculated according to actual calculation₁+C₂+C₃2000pF since 300pF<2000pF<5500pF, so satisfy the agreement requirement, fill electric pile and do not send abnormal information.

The second embodiment is as follows: replacing a test prototype, measuring a 9V PWM specific signal: adjusting internal resistance R of signal driving source ₂70 omega, the rise-fall time is 1.95 us; adjusting internal resistance R of driving source ₂30 omega and the rise-fall time is 1.9us, then according to the actual calculation, the first capacitor C₁+C₂+C₃1250pF since 300pF<1250pF<5500pF, so satisfy agreement requirement and fill electric pile and do not send abnormal information.

The third concrete embodiment: replacing a test prototype, and measuring a 6V PWM specific signal: adjusting internal resistance R of signal driving source₂90 omega, rise and fall time is 1.66 us; adjusting internal resistance R of driving source ₂20 omega and 1.37us rise and fall time, then according to actual calculation, C₁+C₂+C₃4140pF since 300pF<4140pF<5500pF, so satisfy agreement requirement and fill electric pile and do not send abnormal information.

According to the signal abnormity detection method and the charging device provided by the embodiment of the invention, the rising time and/or the falling time of the rising edge of the PWM signal, the contact impedance of the charging gun and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile are monitored, and whether the rising time and/or the falling time of the rising edge of the signal, the contact impedance of the charging gun and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile meet the normal range or not is further judged, if all the values are judged to be normal, the signal is normal, no abnormal information is output, and the real-time signal monitoring is realized.

In addition, referring to fig. 6, an embodiment of the present invention further provides a computer apparatus 300, including: a memory 310 for storing a computer program 320; and a processor 330 for executing the computer program to perform the signal abnormality detection method described above. The computer device 300 may be a charging device.

Referring to fig. 7, a sixth embodiment of the invention further provides a computer storage medium 400 for storing a computer program 410, wherein the computer program 410 is executed to implement the signal anomaly detection method.

The computer-readable storage medium may be an internal storage device of the aforementioned computer device. The computer readable storage medium may also be an external storage device, such as a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), or the like, which is provided on the wireless switch. Further, the computer-readable storage medium may also include both an internal storage unit and an external storage device of the wireless switch. The computer-readable storage medium is used for storing the computer program and other programs and data required by the terminal. The computer readable storage medium may also be used to temporarily store data that has been output or is to be output. The computer program includes program instructions that, when executed by a processor, cause the processor to perform the above-described coordinated routing method for visitor access communities.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

When implemented in software and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention essentially or partially contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A signal abnormality detection method for detecting a Pulse Width Modulation (PWM) signal, the method comprising:

determining the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal not to exceed a first rated value, determining the contact impedance of a charging gun according to a preset rule, and determining the sum of the capacitive reactance of a charging device, the capacitive reactance of a signal line and the capacitive reactance of an electric vehicle; and the number of the first and second groups,

determining that the contact impedance of the charging gun is not in a first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the electric automobile and the capacitive reactance of the signal line is not in a second rated range, and outputting first abnormal information;

wherein after detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, the method further comprises:

determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal exceeds the first rated value, and then improving the driving strength of the PWM signal;

re-detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

determining that the rising time of the rising edge and/or the falling time of the falling edge of the re-detected PWM signal does not exceed a first rated value, re-determining new contact impedance of the charging gun according to the preset rule, and re-determining the sum of new capacitive reactance of the charging device, signal line capacitive reactance and capacitive reactance of the electric vehicle; and the number of the first and second groups,

determining that the contact impedance of the charging gun is not in the first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not in the second rated range, and outputting first abnormal information; or, the contact impedance of the charging gun is determined to be in the first rated range, and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is determined to be in the second rated range, and the re-detection action is repeated.

2. The method of claim 1, wherein the increasing the drive strength of the PWM signal comprises: the internal resistance of the PWM signal driving source is reduced.

3. The method according to claim 1, wherein after determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal do not exceed a first rated value, determining charging gun contact impedance according to a preset rule, and determining a sum of charging device capacitive reactance, signal line capacitive reactance, and electric vehicle capacitive reactance, the method further comprises:

determining that the contact impedance of the charging gun is within the first rated range, and determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is within the second rated range, and continuously detecting the rising time and/or the falling time of the rising edge of the PWM signal; and the number of the first and second groups,

and determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are deviated, and outputting second abnormal information.

4. The method according to claim 3, wherein the continuously detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal, and determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal are deviated, outputs second abnormality information, specifically comprises:

detecting the rising time of the rising edge and the falling time of the falling edge of each PWM signal, determining that the value of the rising time or the falling time of the rising edge of one PWM signal, which is increased compared with the rising time or the falling time obtained by the last detection, exceeds a preset time value, and outputting second abnormal information; alternatively, the first and second electrodes may be,

detecting rising time of rising edge and/or falling time of falling edge of PWM signal every preset time interval, determining that the value of rising time or falling time of rising edge of PWM signal at one time is larger than the value of preset time when rising time or falling time obtained by last detection is increased, and outputting second abnormal information; alternatively, the first and second electrodes may be,

detecting the rising time of the rising edge and the falling time of the falling edge of each PWM signal, determining that the rising time and/or the falling time of the falling edge of a plurality of PWM signals are/is increased in sequence, and outputting second abnormal information; alternatively, the first and second electrodes may be,

and detecting the rising time and/or the falling time of the falling edge of the PWM signal at each preset interval, determining that the rising time and/or the falling time of the falling edge of a plurality of PWM signals are increased in sequence, and outputting second abnormal information.

5. The method according to claim 1, wherein the determining the contact impedance of the charging gun and the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle according to a preset rule specifically comprises:

adjusting internal resistance R of PWM signal driving source₂Detecting the PWM signal at different internal resistances R₂The rising time of the rising edge or the falling time T of the falling edge of the time, and the contact resistance R of the charging gun is calculated according to the following formula₁And calculating the capacitive reactance C of the charging device₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃)：T＝τ*ln((V_H-V_L)/(V_H-V_T))，τ＝R*C＝(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) (ii) a Wherein, V_HFor maximum voltage across the PWM drive source capacitor, V_LIs the minimum voltage, V, across the PWM drive source capacitor_TThe voltage at two ends of a capacitor of a PWM driving source at T moment, tau is a capacitor charging time constant, R₃Is a voltage-dividing resistor of an electric automobile, R₄The voltage dividing resistor is used for the charging device.

6. The method of claim 5, wherein the charging gun contact resistance R is calculated according to the following formula₁And charging device capacitive reactance C₁Capacitive reactance C of electric automobile₂And signal line capacitive reactance C₃The sum of (a) and (b): t ═ τ × ln ((V)_H-V_L)/(V_H-V_T))，τ＝R*C＝(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) And then, further comprising:

and adjusting and restoring the internal resistance R2 of the PWM signal driving source.

7. The method of claim 6, wherein the adjusting the internal resistance R of the PWM signal driving source₂The method specifically comprises the following steps: adjusting internal resistance R of the PWM signal driving source₂The increased resistance value is not less than 30 Ω.

8. The method of claim 1, wherein the first anomaly information comprises contact anomaly information and capacitive load anomaly information.

9. The method of claim 1, wherein the first nominal value comprises 2 μ β; and/or the presence of a gas in the gas,

the first nominal range includes: less than 15m Ω; and/or the presence of a gas in the gas,

the second nominal range includes: 300-5500 pF.

10. A charging apparatus for detecting a PWM signal, the apparatus comprising:

the processing unit is used for determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal do not exceed a first rated value, determining the contact impedance of the charging gun according to a preset rule, and determining the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile; and the number of the first and second groups,

the signal output unit is used for determining that the contact impedance of the charging gun is not in a first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not in a second rated range, and outputting first abnormal information;

wherein the charging device further comprises a signal driving unit:

the signal driving unit is used for determining that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal exceeds the first rated value, and then improving the driving strength of the PWM signal;

the detection unit is further used for re-detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal;

the processing unit is further configured to determine that the rising time of the rising edge and/or the falling time of the falling edge of the re-detected PWM signal does not exceed a first rated value, and then re-determine a new contact impedance of the charging gun according to the preset rule, and re-determine a sum of a new capacitive reactance of the charging device, a new signal line capacitive reactance, and a new capacitive reactance of the electric vehicle;

the signal output unit is further used for determining that the contact impedance of the charging gun is not within the first rated range, and/or determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric automobile is not within the second rated range, and outputting first abnormal information; or determining that the contact impedance of the charging gun is within the first rated range, determining that the sum of the capacitive reactance of the charging device, the capacitive reactance of the signal line and the capacitive reactance of the electric vehicle is within the second rated range, and sending a command of re-detection to the detection unit.

11. The charging device according to claim 10, wherein the signal driving unit is configured to decrease the internal resistance of the PWM signal driving source if it is determined that the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal exceeds the first rated value.

12. The charging device according to claim 10, wherein the detection unit is further configured to determine that the charging gun contact impedance is within a first rated range, and if the sum of the charging device capacitive reactance, the signal line capacitive reactance, and the electric vehicle capacitive reactance is within a second rated range, continuously detect a rising time and/or a falling time of a falling edge of the PWM signal; the signal output unit is further configured to determine that a deviation occurs in a rising time of a rising edge and/or a falling time of a falling edge of the PWM signal, and output second abnormal information.

13. The charging device according to claim 12, wherein the detecting unit is specifically configured to detect a rising time of a rising edge and a falling time of a falling edge of each PWM signal; or detecting the rising time of the rising edge and/or the falling time of the falling edge of the PWM signal at preset time intervals;

the signal output unit is specifically configured to determine that a value of increase of the rising time or the falling time of the rising edge of one of the PWM signals to the value of the rising time or the falling time obtained by the last detection exceeds a preset time value, and output second abnormal information; or determining that the rising time of the rising edge and/or the falling time of the falling edge of a plurality of PWM signals are/is increased in sequence, and outputting second abnormal information.

14. The charging device according to claim 10, further comprising a signal driving unit for adjusting an internal resistance R of the PWM signal driving source₂(ii) a The detection unit is further used for detecting the rising time of the rising edge or the falling time T of the falling edge of the PWM signal under different driving strengths, and the processing unit is further used for calculating the contact resistance R of the charging gun according to the following formula₁And calculating the capacitive reactance C of the charging device₁And a signal line capacitive reactance C₂And capacitive reactance C of electric automobile₃Sum of (C)₁+C₂+C₃)：T＝τ*ln((V_H-V_L)/(V_H-V_T))，τ＝R*C＝(R₂+R₄+R₁+R₃)*(C₁+C₂+C₃) (ii) a Wherein, V_HFor maximum voltage across the PWM drive source capacitor, V_LIs the minimum voltage, V, across the PWM drive source capacitor_TThe voltage at two ends of a capacitor of a PWM driving source at T moment, tau is a capacitor charging time constant, R₃Is a voltage-dividing resistor of an electric automobile, R₄The voltage dividing resistor is used for the charging device.

15. The charging device of claim 14, wherein the signal driving unit is further configured to adjust an internal resistance R2 for restoring the PWM signal driving source.

16. A charging device as claimed in claim 15, wherein the signal driving unit is configured to: adjusting internal resistance R of the PWM signal driving source₂The increased resistance value is not less than 30 Ω.

17. The charging device according to claim 10, wherein the first abnormality information includes contact abnormality information and capacitive load abnormality information.

18. The charging device of claim 10, wherein the first nominal value comprises 2 μ β; and/or the presence of a gas in the gas,

the second nominal range includes: 300-5500 pF.

19. A computer device comprising a processor and a memory, the processor being coupled to the memory and the processor executing instructions in operation to implement a signal anomaly detection method according to any one of claims 1 to 9.

20. A storage medium having stored thereon a computer program to be executed by a processor to implement the signal anomaly detection method according to any one of claims 1 to 9.