Charging pile circuit detection method capable of automatically identifying electric vehicle and load

Abstract

The invention relates to the technical field of power electronics, and discloses a charging pile circuit detection method and system capable of automatically identifying an electric vehicle and a load, and the method comprises the steps: constructing a high-frequency signal injection unit and a signal collection unit of a charging pile, injecting a specific high-frequency detection signal into a corresponding charging line of the charging pile, acquiring a voltage signal and a current signal of the charging circuit; performing time domain analysis on the voltage signal and the current signal, and calculating an impedance value of the charging circuit; performing frequency domain transformation on the voltage signal and the current signal, analyzing harmonic components of frequency domain data, determining transient response of the frequency domain data, and extracting characteristic parameters of the transient response; analyzing an electric vehicle type and a load type of the charging line, analyzing a load state of the charging line, identifying an abnormal state of the load state, constructing an abnormal alarm mechanism of the abnormal state, and determining an abnormal adjustment parameter of the charging pile; and determining a circuit detection scheme of the charging pile. According to the invention, the accuracy and timeliness of charging pile circuit detection can be improved.

Description

Technical Field

[0001] The present invention relates to a charging pile circuit detection method and system for automatically identifying an electric vehicle and a load, belonging to the technical field of power electronics. Background Art

[0002] Charging pile circuit testing uses electrical measurement and signal processing technologies to automatically identify and assess the charging pile's circuit status, connected load type, and potential safety hazards. This testing can promptly detect faults such as short circuits, open circuits, and leakage in the charging pile or connected load, as well as abnormal conditions such as overload, overtemperature, and overvoltage. This allows for timely action to cut off power, prevent electrical fires, and protect personnel and property.

[0003] Traditional charging pile circuit detection methods are based on current / voltage threshold detection. They primarily monitor the current, voltage, or power of the charging circuit. If a preset threshold (such as overcurrent, overvoltage, or undervoltage) is exceeded, a protection measure (such as a circuit breaker) is triggered. However, this method cannot distinguish between load types (such as electric vehicles, resistive loads, or faulty equipment). It can only perform simple circuit parameter measurements and fault protection, and cannot implement more advanced functions, resulting in poor circuit detection results. Summary of the Invention

[0004] The present invention provides a charging pile circuit detection method and system for automatically identifying electric vehicles and loads, the main purpose of which is to improve the accuracy and timeliness of charging pile circuit detection.

[0005] To achieve the above objectives, the present invention provides a charging pile circuit detection method for automatically identifying electric vehicles and loads, comprising: Constructing a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determining signal parameters of the high-frequency signal injection unit, injecting a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit based on the signal parameters, and acquiring a voltage signal and a current signal of the charging line through the signal acquisition unit based on the high-frequency detection signal; performing time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculating an impedance value of the charging circuit based on the effective voltage value and the effective current value; Performing frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyzing harmonic components of the frequency domain data, determining a transient response of the frequency domain data based on the harmonic components, and extracting characteristic parameters of the transient response; Analyzing the electric vehicle type and load type of the charging circuit according to the impedance value and the characteristic parameter, analyzing the load state of the charging circuit according to the electric vehicle type and the load type, identifying an abnormal state of the load state, establishing an abnormal alarm mechanism for the abnormal state, and determining an abnormal adjustment parameter of the charging pile based on the abnormal state; Based on the load status, the abnormal alarm mechanism and the abnormal adjustment parameter, a circuit detection scheme for the charging pile is determined.

[0006] Optionally, the high-frequency signal injection unit and signal acquisition unit for constructing the charging pile include: Clarify the circuit testing requirements of the charging pile; Determine the amplitude range and injection method of the charging pile according to the circuit detection requirements; Determining a signal generator of the charging pile, and determining a power amplification circuit of the signal generator based on the amplitude range; determining a coupling circuit of the signal generator based on the injection mode; According to the coupling circuit, the power amplifier circuit and the signal generator, a high-frequency signal injection unit of the charging pile is integrated; Determine the signal sampling rate and signal resolution of the charging pile according to the circuit detection requirements; Configuring the sensor of the charging pile according to the signal sampling rate; Determining a signal conditioning circuit and an analog-to-digital converter connected to the sensor based on the signal resolution; A signal acquisition unit of the charging pile is integrated according to the sensor, the signal conditioning circuit and the analog-to-digital converter.

[0007] Optionally, the collecting, by the signal collection unit, the voltage signal and the current signal of the charging circuit based on the high-frequency detection signal includes: Based on the high-frequency detection signal, collecting a feedback signal of the charging circuit by the signal collection unit; analyzing signal characteristics and interference types of the feedback signal, and filtering the feedback signal based on the signal characteristics and the interference type to obtain a filtered signal; amplifying the filtered signal to obtain an amplified signal; Performing analog-to-digital conversion on the amplified signal to obtain a converted signal; The converted signal is extracted according to the signal sampling rate corresponding to the signal acquisition unit to obtain a voltage signal and a current signal.

[0008] Optionally, performing time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value includes: uniformly determining the sampling windows and sampling time points of the voltage signal and the current signal; Determining a window length of the sampling window; Determine the voltage value and current value corresponding to the sampling time point; The effective voltage value and effective current value of the voltage signal and the current signal are calculated according to the voltage value, the current value, and the window length using the following formula: ; ; ; ; in, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The voltage value when Indicates the sampling time point The voltage value when Indicates the window length, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The current value when Indicates the sampling time point The current value when .

[0009] Optionally, calculating the impedance value of the charging circuit according to the effective voltage value and the effective current value includes: Calculating the voltage root mean square (RMS) and current root mean square (RMS) of the effective voltage value and the effective current value, respectively; calculating the apparent power of the charging circuit based on the voltage root mean square and the voltage root mean square; Based on the effective voltage value and the effective current value, the actual power of the charging circuit is calculated using the following formula: ; in, Indicates the actual power, Indicates the detection cycle, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates time Perform integration; Calculating a power factor of the charging circuit according to the actual power and the apparent power; calculating the resistance and reactance of the charging circuit respectively according to the power factor; An impedance value of the charging line is determined based on the resistance and the reactance.

[0010] Optionally, performing frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data includes: Determine a window function of the voltage signal and the current signal, wherein the window function includes: ; in, represents the output signal of the window function, Indicates the sampling points, cosine function, represents pi, Indicates the signal length; Based on the window function, the voltage signal and the current signal are windowed to obtain a windowed voltage signal and a windowed current signal; The windowed voltage signal and the windowed current signal are converted using the following formula to obtain frequency domain data: ; ; in, The first frequency components, The first frequency components, represents the frequency index, Indicates the sampling points, Indicates the signal length, represents the voltage signal after windowing, represents the current signal after windowing, Indicates The exponential function with base , represents the imaginary unit, Represents pi.

[0011] Optionally, analyzing the transient response of the frequency domain data includes: Extracting frequency points of interest of the harmonic components; Determining the complex spectrum value of the frequency point of interest; constructing an interest spectrum of the frequency domain data according to the interest frequency points and the complex spectrum values; Performing an inverse time domain transformation on the spectrum of interest to obtain a complex sequence; A real number portion of the complex number sequence is extracted, and a transient response of the frequency domain data is determined based on the real number portion.

[0012] Optionally, analyzing the electric vehicle type and load type of the charging line according to the impedance value and the characteristic parameter includes: Acquiring electric vehicle data and electrical characteristic data corresponding to the charging line; Building a type analysis database of the charging line based on the electric vehicle data and the electrical characteristic data; Calculating the automobile category similarity and the load category similarity in the type analysis database according to the impedance value and the characteristic parameter; The electric vehicle type and the load type of the charging line are determined according to the vehicle type similarity and the load type similarity.

[0013] Optionally, analyzing the load state of the charging circuit according to the electric vehicle type and the load type includes: Extracting electric vehicle characteristics and load characteristics of the electric vehicle corresponding to the charging line according to the electric vehicle type and the load type; Calculating an instantaneous power demand curve of the electric vehicle according to the electric vehicle characteristics and the load characteristics; identifying a peak power of the instantaneous power demand curve; Calculating a real-time load rate of the charging circuit according to the peak power and a corresponding instantaneous response of the charging circuit; The load state of the charging circuit is determined according to the real-time load rate.

[0014] In order to solve the above problems, the present invention also provides a charging pile circuit detection system for automatically identifying electric vehicles and loads, the system comprising: A signal detection module is used to construct a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determine the signal parameters of the high-frequency signal injection unit, and based on the signal parameters, inject a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit. Based on the high-frequency detection signal, the signal acquisition unit collects the voltage signal and current signal of the charging line; an impedance value analysis module, configured to perform time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculate the impedance value of the charging circuit based on the effective voltage value and the effective current value; an electrical parameter analysis module, configured to perform frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyze harmonic components of the frequency domain data, determine a transient response of the frequency domain data based on the harmonic components, and extract characteristic parameters of the transient response; a state detection module, configured to analyze the electric vehicle type and load type of the charging circuit according to the impedance value and the characteristic parameter, analyze the load state of the charging circuit according to the electric vehicle type and the load type, identify abnormal states of the load state, establish an abnormal alarm mechanism for the abnormal state, and determine abnormal adjustment parameters of the charging pile based on the abnormal state; A detection scheme generating module is used to determine a circuit detection scheme for the charging pile based on the load state, the abnormal alarm mechanism and the abnormal adjustment parameter.

[0015] Compared with the problems described in the background technology, the embodiment of the present invention can accurately locate the physical location of the fault by injecting a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit based on the signal parameters, and can accurately locate the physical location of the fault by analyzing the reflected wave or attenuation mode generated by the injected signal at the fault point (such as short circuit, open circuit, poor contact, insulation damage, etc.); optionally, the embodiment of the present invention can comprehensively reflect the resistance loss of the conductor material in the charging line and the reactance effect generated by the inductance and capacitance of the line according to the effective voltage value and the effective current value, which is helpful to fully understand the electrical characteristics of the line; the embodiment of the present invention can decompose complex time domain signals into different The sine and cosine components of the frequency are determined based on the harmonic components, thereby revealing the frequency composition of the signal; the embodiment of the present invention can monitor the stability of the charging circuit in real time by determining the transient response of the frequency domain data based on the harmonic components, promptly discover and respond to transient events, and improve the reliability and safety of the charging process; the embodiment of the present invention can monitor the stability of the charging circuit in real time by determining the transient response of the frequency domain data based on the harmonic components, promptly discover and respond to transient events, and improve the reliability and safety of the charging process; finally, the embodiment of the present invention can determine the circuit detection scheme of the charging pile based on the load status, the abnormal alarm mechanism and the abnormal adjustment parameters: by real-time monitoring of the circuit status, timely discovering and handling abnormalities, preventing electrical faults such as short circuits, overloads, and leakages, and reducing the risk of fire and electric shock. Therefore, the charging pile circuit detection method and system for automatically identifying electric vehicles and loads provided by the embodiment of the present invention can improve the accuracy and timeliness of charging pile circuit detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic flow chart of a charging pile circuit detection method for automatically identifying electric vehicles and loads provided in one embodiment of the present invention; Figure 2 A schematic diagram of a module for implementing the charging pile circuit detection method for automatically identifying electric vehicles and loads provided in one embodiment of the present invention.

[0017] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0018] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] The embodiment of the present application provides a charging pile circuit detection method for automatically identifying electric vehicles and loads. The execution subject of the charging pile circuit detection method for automatically identifying electric vehicles and loads includes but is not limited to at least one of the electronic devices such as a server and a terminal that can be configured to execute the method provided by the embodiment of the present application. In other words, the charging pile circuit detection method for automatically identifying electric vehicles and loads can be executed by software or hardware installed on a terminal device or a server device. The server includes but is not limited to: a single server, a server cluster, a cloud server or a cloud server cluster, etc.

[0020] Example 1: Reference Figure 1 FIG2 is a flow chart of a method for detecting a charging pile circuit for automatically identifying an electric vehicle and a load according to an embodiment of the present invention. In this embodiment, the method for detecting a charging pile circuit for automatically identifying an electric vehicle and a load includes: S1. Construct a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determine the signal parameters of the high-frequency signal injection unit, and based on the signal parameters, inject a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit. Based on the high-frequency detection signal, collect the voltage signal and current signal of the charging line through the signal acquisition unit.

[0021] The embodiments of the present invention implement real-time monitoring of the charging circuit by constructing a high-frequency signal injection unit and a signal acquisition unit for the charging pile and analyzing the propagation characteristics of the high-frequency signal. The high-frequency signal injection unit is a device for generating and injecting a specific high-frequency detection signal into the charging circuit. The signal acquisition unit is a device for collecting voltage and current signals on the charging circuit.

[0022] As an embodiment of the present invention, the high-frequency signal injection unit and signal acquisition unit for constructing the charging pile include: Clarify the circuit testing requirements of the charging pile; Determine the amplitude range and injection method of the charging pile according to the circuit detection requirements; Determining a signal generator of the charging pile, and determining a power amplification circuit of the signal generator based on the amplitude range; determining a coupling circuit of the signal generator based on the injection mode; According to the coupling circuit, the power amplifier circuit and the signal generator, a high-frequency signal injection unit of the charging pile is integrated; Determine the signal sampling rate and signal resolution of the charging pile according to the circuit detection requirements; Configuring the sensor of the charging pile according to the signal sampling rate; Determining a signal conditioning circuit and an analog-to-digital converter connected to the sensor based on the signal resolution; A signal acquisition unit of the charging pile is integrated according to the sensor, the signal conditioning circuit and the analog-to-digital converter.

[0023] The circuit detection requirements refer to the specific requirements for electrical performance and status monitoring of charging piles and their associated circuit systems to ensure their safe, reliable, and efficient operation. The amplitude range refers to the amplitude range of the voltage or current corresponding to the high-frequency signal generated by the high-frequency signal injection unit. The injection method refers to the specific method of introducing the high-frequency signal into the charging circuit, such as series injection, parallel injection, and coupled injection. The signal generator refers to an electronic device used to generate an electrical signal of a specific frequency, waveform, and amplitude. The power amplifier circuit refers to an electronic circuit used to amplify the electrical signal generated by the signal generator. The coupling circuit refers to an electronic circuit used to effectively couple the high-frequency detection signal generated by the high-frequency signal injection unit into the charging circuit. The signal sampling rate refers to the number of times the signal acquisition unit samples the voltage and current signals of the charging circuit per unit time. The signal resolution refers to the degree of precision with which the signal acquisition unit quantifies the signal amplitude when converting the analog signal into a digital signal. The sensor refers to a device used to detect relevant electrical signals during the charging process, such as a current sensor or voltage sensor. The signal conditioning circuit is an electronic circuit located between the sensor and the analog-to-digital converter (ADC). It is used to pre-process the electrical signal output by the sensor so that the ADC can more efficiently convert it into a digital signal. The ADC is an electronic circuit used to convert analog signals into digital signals.

[0024] Optionally, the power amplifier circuit of the signal generator can be determined by multi-physics field simulation, such as simulating multiple power amplifier circuits of the signal generator through multi-physics field simulation technology, analyzing the amplifier circuit performance of the multiple power amplifier circuits, and screening out the best power amplifier circuit among the multiple power amplifier circuits based on the amplifier circuit performance.

[0025] In embodiments of the present invention, by determining the signal parameters of the high-frequency signal injection unit, the signal-to-noise ratio can be optimized by selecting appropriate frequency and amplitude, thereby improving detection accuracy. The signal parameters refer to the characteristics of the high-frequency signal injected into the charging circuit, such as frequency, amplitude, waveform, etc.

[0026] Optionally, the signal parameters of the high-frequency signal injection unit can be determined by generating an adversarial network and a simulation environment, such as generating virtual signal parameters of the high-frequency signal injection unit by generating an adversarial network, simulating the detection environment of the high-frequency signal injection unit through a simulation environment based on the virtual signal parameters, determining the validity of the virtual signal parameters according to the detection environment, and determining the signal parameters of the high-frequency signal injection unit based on the validity.

[0027] In this embodiment of the present invention, based on the signal parameters, the high-frequency signal injection unit injects a specific high-frequency detection signal into the charging line corresponding to the charging pile. By analyzing the reflected wave or attenuation pattern generated by the injected signal at the fault point (such as a short circuit, open circuit, poor contact, insulation damage, etc.), the physical location of the fault can be accurately located. The high-frequency detection signal is an electrical signal with a specific frequency, amplitude, and waveform.

[0028] In this embodiment of the present invention, the signal acquisition unit collects the voltage and current signals of the charging circuit based on the high-frequency detection signal, and can monitor the status of the charging circuit in real time by analyzing the collected voltage and current signals. The voltage signal is an important parameter used to measure the charge distribution and energy transfer state in the circuit. The current signal is an important parameter used to measure the energy transfer state in the circuit.

[0029] As an embodiment of the present invention, the collecting, by the signal collection unit, the voltage signal and the current signal of the charging circuit based on the high-frequency detection signal includes: Based on the high-frequency detection signal, collecting a feedback signal of the charging circuit by the signal collection unit; analyzing signal characteristics and interference types of the feedback signal, and filtering the feedback signal based on the signal characteristics and the interference type to obtain a filtered signal; amplifying the filtered signal to obtain an amplified signal; Performing analog-to-digital conversion on the amplified signal to obtain a converted signal; The converted signal is extracted according to the signal sampling rate corresponding to the signal acquisition unit to obtain a voltage signal and a current signal.

[0030] The feedback signal refers to a signal collected from the charging circuit that contains information about the circuit status and performance. The signal characteristics refer to the properties and characteristics inherent in the signal itself that can be used to describe and distinguish the signal, such as frequency characteristics, amplitude characteristics, waveform characteristics, etc. The interference type refers to various electromagnetic interferences that affect the transmission and reception of high-frequency detection signals, such as electromagnetic interference, radio frequency interference, and power frequency interference. The filtered signal refers to the result of the feedback signal being processed by a filter. The amplified signal refers to the result of the filtered signal being processed by an amplifier. The converted signal refers to the result of the amplified signal being processed by an analog-to-digital converter.

[0031] Optionally, the signal characteristics and interference type of the feedback signal can be analyzed through wavelet transform analysis, such as analyzing the local characteristics of the feedback signal through wavelet transform, identifying the interference signal of the feedback signal based on the local characteristics, determining the interference type of the feedback signal based on the interference signal, and extracting the signal characteristics of the feedback signal.

[0032] Optionally, the filtered signal can be obtained by selecting a suitable filter, such as a low-pass filter, a high-pass filter or a band-pass filter.

[0033] S2. Perform time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculate the impedance value of the charging circuit according to the effective voltage value and the effective current value.

[0034] The embodiments of the present invention perform time-domain analysis on the voltage and current signals to obtain effective voltage and effective current values. By calculating the effective voltage and effective current values, the actual effects of voltage and current in the charging circuit can be accurately evaluated, thereby more accurately understanding circuit performance. The effective voltage value is a parameter used to characterize the magnitude of the AC voltage. The effective current value is a parameter used to characterize the magnitude of the AC current.

[0035] As an embodiment of the present invention, performing time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value includes: uniformly determining the sampling windows and sampling time points of the voltage signal and the current signal; Determining a window length of the sampling window; Determine the voltage value and current value corresponding to the sampling time point; The effective voltage value and effective current value of the voltage signal and the current signal are calculated according to the voltage value, the current value, and the window length using the following formula: ; ; ; ; in, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The voltage value when Indicates the sampling time point The voltage value when Indicates the window length, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The current value when Indicates the sampling time point The current value when .

[0036] The sampling window refers to the time interval used to calculate the effective values of the voltage and current signals. The sampling time points refer to the specific moments in time during signal acquisition when the instantaneous values of the voltage and current signals are collected. The window length refers to the duration of the time period used to calculate the effective values. The voltage value refers to the instantaneous voltage value measured by the sampling circuit at a specific sampling time point. The current value refers to the instantaneous current value measured by the sampling circuit at a specific sampling time point.

[0037] By calculating the impedance of the charging circuit based on the effective voltage and current values, the embodiment of the present invention can comprehensively reflect the resistive losses of the conductor material in the charging circuit and the reactance effects generated by the inductance and capacitance of the circuit, thereby facilitating a comprehensive understanding of the electrical characteristics of the circuit. The impedance value is a complex parameter calculated from the voltage and current responses generated by the injected high-frequency signal on the charging circuit.

[0038] As an embodiment of the present invention, calculating the impedance value of the charging circuit according to the effective voltage value and the effective current value includes: Calculating the voltage root mean square (RMS) and current root mean square (RMS) of the effective voltage value and the effective current value, respectively; calculating the apparent power of the charging circuit based on the voltage root mean square and the voltage root mean square; Based on the effective voltage value and the effective current value, the actual power of the charging circuit is calculated using the following formula: ; in, Indicates the actual power, Indicates the detection cycle, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates time Perform integration; Calculating a power factor of the charging circuit according to the actual power and the apparent power; calculating the resistance and reactance of the charging circuit respectively according to the power factor; An impedance value of the charging line is determined based on the resistance and the reactance.

[0039] The RMS voltage is a parameter used to measure the magnitude of AC voltage. The RMS current is a parameter used to measure the magnitude of AC current. The apparent power is the product of the RMS voltage and the RMS current in a circuit. The real power is the power actually consumed or converted into a useful form in a circuit. The power factor is the ratio of real power to apparent power. The resistance is the resistive component corresponding to the real part of impedance. The reactance is the resistance to current caused by the presence of inductance or capacitance.

[0040] Optionally, the apparent power of the charging circuit may be obtained by calculating the product of the root mean square voltage and the root mean square voltage.

[0041] Optionally, the resistance of the charging circuit can be calculated using Ohm's law.

[0042] S3. Perform frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyze the harmonic components of the frequency domain data, determine the transient response of the frequency domain data based on the harmonic components, and extract characteristic parameters of the transient response.

[0043] In this embodiment of the present invention, frequency domain data obtained by performing frequency domain transformation on the voltage and current signals can decompose complex time domain signals into sine and cosine components of different frequencies, thereby revealing the frequency composition of the signals. Frequency domain data refers to the data representation obtained by converting a time domain signal into the frequency domain through a mathematical transformation (such as a Fourier transform).

[0044] As an embodiment of the present invention, performing frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data includes: Determine a window function of the voltage signal and the current signal, wherein the window function includes: ; in, represents the output signal of the window function, Indicates the sampling points, cosine function, represents pi, Indicates the signal length; Based on the window function, the voltage signal and the current signal are windowed to obtain a windowed voltage signal and a windowed current signal; The windowed voltage signal and the windowed current signal are converted using the following formula to obtain frequency domain data: ; ; in, The first frequency components, The first frequency components, represents the frequency index, Indicates the sampling points, Indicates the signal length, represents the voltage signal after windowing, represents the current signal after windowing, Indicates The exponential function with base , represents the imaginary unit, Represents pi.

[0045] The window function is a function used to weight signals in signal processing. The windowed voltage signal is a new voltage signal obtained by multiplying a voltage signal by a defined window function, and the windowed current signal is a new current signal obtained by multiplying a current signal by a defined window function. The frequency index is a serial number used to identify different frequency components in frequency domain data.

[0046] Optionally, the window function may be determined by an optimization algorithm, such as a genetic algorithm, a particle swarm optimization, or the like.

[0047] The embodiment of the present invention can help optimize signal transmission and reduce distortion and interference by analyzing the harmonic components of the frequency domain data. The harmonic components refer to frequency components in the signal whose frequencies are integer multiples of the fundamental frequency.

[0048] Optionally, the harmonic components of the frequency domain data can be analyzed by a spectrum analysis method, such as constructing a spectrum graph of the frequency domain data by a spectrum analysis method, identifying the peak position and amplitude of the spectrum graph, and determining the harmonic components of the frequency domain data based on the peak position and the amplitude.

[0049] By determining the transient response of the frequency domain data based on the harmonic components, embodiments of the present invention can monitor the stability of the charging circuit in real time, promptly detect and respond to transient events, and improve the reliability and safety of the charging process. The transient response refers to the output reaction of the charging circuit to the input signal at a specific moment.

[0050] As an embodiment of the present invention, analyzing the transient response of the frequency domain data includes: Extracting frequency points of interest of the harmonic components; Determining the complex spectrum value of the frequency point of interest; constructing an interest spectrum of the frequency domain data according to the interest frequency points and the complex spectrum values; Performing an inverse time domain transformation on the spectrum of interest to obtain a complex sequence; A real number portion of the complex number sequence is extracted, and a transient response of the frequency domain data is determined based on the real number portion.

[0051] The frequency point of interest refers to the frequency component that is critical for analyzing transient responses. The complex spectrum value refers to the complex result associated with the frequency point of interest. The spectrum of interest refers to the portion of the spectrum extracted from the entire spectrum that is critical for analyzing transient responses. The complex sequence refers to a series of complex values obtained after inverse time domain transformation. The real part refers to the real part of a complex sequence.

[0052] Optionally, the complex sequence can be obtained by a time domain inverse conversion algorithm, such as discrete Fourier transform DFT or its inverse transform.

[0053] By extracting characteristic parameters of the transient response, embodiments of the present invention can assess the dynamics of the charging circuit and identify potential faults in the charging circuit. These characteristic parameters are key quantitative indicators that describe the signal's behavior in the time domain, such as rise time, settling time, and number of oscillations.

[0054] Optionally, the characteristic parameters of the transient response can be extracted by a machine learning algorithm, such as a support vector machine, a decision tree, a random forest, etc.

[0055] S4. Analyze the electric vehicle type and load type of the charging line according to the impedance value and the characteristic parameters, analyze the load state of the charging line according to the electric vehicle type and the load type, identify the abnormal state of the load state, establish an abnormal alarm mechanism for the abnormal state, and determine the abnormal adjustment parameters of the charging pile based on the abnormal state.

[0056] In embodiments of the present invention, by analyzing the electric vehicle type and load type of the charging circuit based on the impedance value and the characteristic parameters, the charging current and voltage can be adjusted to achieve faster and safer charging. The electric vehicle type refers to a specific classification or type of electric vehicle, such as a lithium-ion battery electric vehicle or a lead-acid battery electric vehicle. The load type refers to the type of electrical equipment connected to the charging circuit.

[0057] As an embodiment of the present invention, analyzing the electric vehicle type and load type of the charging line according to the impedance value and the characteristic parameter includes: Acquiring electric vehicle data and electrical characteristic data corresponding to the charging line; Building a type analysis database of the charging line based on the electric vehicle data and the electrical characteristic data; Calculating the automobile category similarity and the load category similarity in the type analysis database according to the impedance value and the characteristic parameter; The electric vehicle type and the load type of the charging line are determined according to the vehicle type similarity and the load type similarity.

[0058] The electric vehicle data refers to various information related to electric vehicles, such as vehicle information, battery information, and charging information. The electrical characteristic data refers to the electrical parameters and characteristics measured for the electric vehicle itself. The type analysis database refers to a database system specifically used to store, manage, and analyze data related to electric vehicles and their charging. The vehicle category similarity refers to an indicator that measures the degree of similarity between different types of electric vehicles in terms of charging behavior, electrical characteristics, or usage patterns. The load category similarity refers to an indicator that measures the degree of similarity between different types of loads in terms of electrical characteristics, power requirements, and power usage behavior.

[0059] Optionally, the electric vehicle data and electrical characteristic data corresponding to the charging line can be obtained through big data mining, such as association rule mining, SQL language, etc.

[0060] Optionally, the vehicle category similarity and the load category similarity in the type analysis database may be calculated using a similarity algorithm, such as Euclidean distance, Mahalanobis distance, cosine similarity, and the like.

[0061] By analyzing the load status of the charging circuit based on the electric vehicle type and the load type, embodiments of the present invention can promptly detect abnormal conditions such as overload, underload, or imbalance, and issue warning signals to prevent equipment damage or safety accidents. The load status refers to the power load borne by the charging circuit at a specific moment.

[0062] As an embodiment of the present invention, analyzing the load state of the charging line according to the electric vehicle type and the load type includes: Extracting electric vehicle characteristics and load characteristics of the electric vehicle corresponding to the charging line according to the electric vehicle type and the load type; Calculating an instantaneous power demand curve of the electric vehicle according to the electric vehicle characteristics and the load characteristics; identifying a peak power of the instantaneous power demand curve; Calculating a real-time load rate of the charging circuit according to the peak power and a corresponding instantaneous response of the charging circuit; The load state of the charging circuit is determined according to the real-time load rate.

[0063] The electric vehicle characteristics refer to the specific attributes and parameters used to describe and distinguish different electric vehicles, such as battery capacity, current battery status, and charge rate limits. The load characteristics refer to the specific attributes and parameters used to describe and distinguish various loads connected to the charging line, such as power demand, current demand, and voltage demand. The instantaneous power demand curve is a continuous representation of the total power demand on the charging line over time within a specific time range. The peak power refers to the maximum instantaneous power value reached by the electric vehicle charging line and electrical load. The real-time load rate refers to the ratio between the actual load of the charging line and its maximum tolerable load.

[0064] Optionally, the instantaneous power demand curve of the electric vehicle can be calculated by combining physical modeling and data-driven methods, such as calculating the power demand of the electric vehicle through a physical model based on the electric vehicle characteristics and the load characteristics, fitting the initial power demand curve of the electric vehicle based on the power demand, determining the optimization parameters of the initial power demand curve through the data-driven method, and determining the instantaneous power demand curve of the electric vehicle based on the optimization parameters.

[0065] Optionally, the peak power of the instantaneous power demand curve may be calculated using a data analysis algorithm, such as a sliding window maximum value, a peak detection algorithm, or the like.

[0066] By identifying abnormal load conditions, embodiments of the present invention can promptly detect abnormal conditions such as overload, short circuit, and leakage, thereby preventing damage to charging equipment, electric vehicle batteries, or power grid equipment due to overheating, overcurrent, etc. The abnormal condition refers to any potentially dangerous load condition compared to a normal operating state, such as overload, short circuit, and leakage.

[0067] By establishing the abnormal state alarm mechanism described above, embodiments of the present invention can detect potential problems in advance through abnormal state monitoring and alarm, reduce the impact of abnormal states on the system, prevent the situation from escalating, and minimize losses. The abnormal state alarm mechanism refers to a set of technologies for monitoring, detecting, reporting, and handling abnormal states in the charging circuit.

[0068] Optionally, the abnormal alarm mechanism of the abnormal state can be constructed through adaptive thresholds and dynamic benchmarks, such as determining the alarm threshold of the abnormal state through adaptive thresholds, and analyzing the state change of the abnormal state through dynamic benchmarks, and constructing the abnormal alarm mechanism of the abnormal state based on the alarm threshold and the state change.

[0069] By determining the abnormal adjustment parameters of the charging pile based on the abnormal state, embodiments of the present invention can timely adjust the charging parameters, thereby preventing charging circuit collapse, reducing voltage fluctuations caused by sudden load changes, and improving charging stability. The abnormal adjustment parameters refer to parameters that need to be adjusted to protect equipment safety, maintain stable system operation, or optimize the charging process when an abnormal state is detected, such as charging power, charging voltage, and charging current.

[0070] Optionally, the abnormal adjustment parameters of the charging pile can be determined by a multi-objective optimization algorithm, such as a genetic algorithm, a particle swarm optimization algorithm, or the like.

[0071] S5. Determine a circuit detection scheme for the charging pile based on the load state, the abnormal alarm mechanism, and the abnormal adjustment parameter.

[0072] The embodiment of the present invention determines the circuit detection scheme of the charging pile based on the load status, the abnormal alarm mechanism and the abnormal adjustment parameters. It can: timely discover and handle abnormalities by real-time monitoring of the circuit status, prevent electrical faults such as short circuit, overload, leakage, etc., and reduce the risk of fire and electric shock.

[0073] Compared with the problems described in the background technology, the embodiment of the present invention can accurately locate the physical location of the fault by injecting a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit based on the signal parameters, and can accurately locate the physical location of the fault by analyzing the reflected wave or attenuation mode generated by the injected signal at the fault point (such as short circuit, open circuit, poor contact, insulation damage, etc.); optionally, the embodiment of the present invention can comprehensively reflect the resistance loss of the conductor material in the charging line and the reactance effect generated by the inductance and capacitance of the line according to the effective voltage value and the effective current value, which is helpful to fully understand the electrical characteristics of the line; the embodiment of the present invention can decompose complex time domain signals into different The sine and cosine components of the frequency are determined based on the harmonic components, thereby revealing the frequency composition of the signal; the embodiment of the present invention can monitor the stability of the charging circuit in real time by determining the transient response of the frequency domain data based on the harmonic components, promptly discover and respond to transient events, and improve the reliability and safety of the charging process; the embodiment of the present invention can monitor the stability of the charging circuit in real time by determining the transient response of the frequency domain data based on the harmonic components, promptly discover and respond to transient events, and improve the reliability and safety of the charging process; finally, the embodiment of the present invention can determine the circuit detection scheme of the charging pile based on the load status, the abnormal alarm mechanism and the abnormal adjustment parameters: by real-time monitoring of the circuit status, timely discovering and handling abnormalities, preventing electrical faults such as short circuits, overloads, and leakages, and reducing the risk of fire and electric shock. Therefore, the charging pile circuit detection method and system for automatically identifying electric vehicles and loads provided by the embodiment of the present invention can improve the accuracy and timeliness of charging pile circuit detection.

[0074] Example 2: like Figure 2 FIG. 1 is a functional module diagram of a charging pile circuit detection system for automatically identifying electric vehicles and loads according to the present invention.

[0075] The charging pile circuit detection system 200 for automatically identifying electric vehicles and loads described in the present invention can be installed in an electronic device. Depending on the functionality implemented, the system can include a signal detection module 201, an impedance value analysis module 202, an electrical parameter analysis module 203, a state detection module 204, and a detection solution generation module 205. The modules described in the present invention, also referred to as units, refer to a series of computer program segments that can be executed by an electronic device processor and perform a fixed function, and are stored in the electronic device's memory.

[0076] In the embodiment of the present invention, the functions of each module / unit are as follows: The signal detection module 201 is used to construct a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determine the signal parameters of the high-frequency signal injection unit, and based on the signal parameters, inject a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit. Based on the high-frequency detection signal, the signal acquisition unit collects the voltage signal and current signal of the charging line; The impedance value analysis module 202 is configured to perform time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculate the impedance value of the charging circuit based on the effective voltage value and the effective current value; The electrical parameter analysis module 203 is configured to perform frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyze the harmonic components of the frequency domain data, determine the transient response of the frequency domain data based on the harmonic components, and extract characteristic parameters of the transient response; The state detection module 204 is configured to analyze the electric vehicle type and load type of the charging circuit according to the impedance value and the characteristic parameter, analyze the load state of the charging circuit according to the electric vehicle type and the load type, identify abnormal states of the load state, establish an abnormal alarm mechanism for the abnormal state, and determine abnormal adjustment parameters of the charging pile based on the abnormal state; The detection scheme generating module 205 is configured to determine a circuit detection scheme for the charging pile based on the load status, the abnormality alarm mechanism, and the abnormality adjustment parameter.

[0077] In detail, the modules in the charging pile circuit detection system 200 for automatically identifying electric vehicles and loads in the embodiment of the present invention are used in the same manner as above. Figure 1 The same technical means as the charging pile circuit detection method for automatically identifying electric vehicles and loads described in the text and can produce the same technical effects are not described here.

[0078] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A charging pile circuit detection method for automatically identifying electric vehicles and loads, characterized in that: The method comprises: Constructing a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determining signal parameters of the high-frequency signal injection unit, injecting a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit based on the signal parameters, and acquiring a voltage signal and a current signal of the charging line through the signal acquisition unit based on the high-frequency detection signal; performing time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculating an impedance value of the charging circuit based on the effective voltage value and the effective current value; Performing frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyzing harmonic components of the frequency domain data, determining a transient response of the frequency domain data based on the harmonic components, and extracting characteristic parameters of the transient response; Analyzing the electric vehicle type and load type of the charging circuit according to the impedance value and the characteristic parameter, analyzing the load state of the charging circuit according to the electric vehicle type and the load type, identifying an abnormal state of the load state, establishing an abnormal alarm mechanism for the abnormal state, and determining an abnormal adjustment parameter of the charging pile based on the abnormal state; Based on the load status, the abnormal alarm mechanism and the abnormal adjustment parameter, a circuit detection scheme for the charging pile is determined.

2. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The high-frequency signal injection unit and signal acquisition unit for constructing the charging pile include: Clarify the circuit testing requirements of the charging pile; Determine the amplitude range and injection method of the charging pile according to the circuit detection requirements; Determining a signal generator of the charging pile, and determining a power amplification circuit of the signal generator based on the amplitude range; determining a coupling circuit of the signal generator based on the injection mode; According to the coupling circuit, the power amplifier circuit and the signal generator, a high-frequency signal injection unit of the charging pile is integrated; Determine the signal sampling rate and signal resolution of the charging pile according to the circuit detection requirements; Configuring the sensor of the charging pile according to the signal sampling rate; Determining a signal conditioning circuit and an analog-to-digital converter connected to the sensor based on the signal resolution; A signal acquisition unit of the charging pile is integrated according to the sensor, the signal conditioning circuit and the analog-to-digital converter.

3. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The collecting, by the signal collecting unit, the voltage signal and the current signal of the charging circuit based on the high-frequency detection signal includes: Based on the high-frequency detection signal, collecting a feedback signal of the charging circuit by the signal collection unit; analyzing signal characteristics and interference types of the feedback signal, and filtering the feedback signal based on the signal characteristics and the interference type to obtain a filtered signal; amplifying the filtered signal to obtain an amplified signal; Performing analog-to-digital conversion on the amplified signal to obtain a converted signal; The converted signal is extracted according to the signal sampling rate corresponding to the signal acquisition unit to obtain a voltage signal and a current signal.

4. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The performing time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value includes: uniformly determining the sampling windows and sampling time points of the voltage signal and the current signal; Determining a window length of the sampling window; Determine the voltage value and current value corresponding to the sampling time point; The effective voltage value and effective current value of the voltage signal and the current signal are calculated according to the voltage value, the current value, and the window length using the following formula: ； ； ； ； in, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The cumulative sum of squares of the voltage at Indicates the sampling time point The voltage value when Indicates the sampling time point The voltage value when Indicates the window length, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The cumulative sum of squares of the currents, Indicates the sampling time point The current value when Indicates the sampling time point The current value when .

5. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The calculating the impedance value of the charging circuit according to the effective voltage value and the effective current value includes: Calculating the voltage root mean square (RMS) and current root mean square (RMS) of the effective voltage value and the effective current value, respectively; calculating the apparent power of the charging circuit based on the voltage root mean square and the voltage root mean square; Based on the effective voltage value and the effective current value, the actual power of the charging circuit is calculated using the following formula: ； in, Indicates the actual power, Indicates the detection cycle, Indicates the sampling time point The effective voltage value when Indicates the sampling time point The effective current value when Indicates time Perform integration; Calculating a power factor of the charging circuit according to the actual power and the apparent power; calculating the resistance and reactance of the charging circuit respectively according to the power factor; An impedance value of the charging line is determined based on the resistance and the reactance.

6. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The performing frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data includes: Determine a window function of the voltage signal and the current signal, wherein the window function includes: ； in, represents the output signal of the window function, Indicates the sampling points, cosine function, represents pi, Indicates the signal length; Based on the window function, the voltage signal and the current signal are windowed to obtain a windowed voltage signal and a windowed current signal; The windowed voltage signal and the windowed current signal are converted using the following formula to obtain frequency domain data: ； ； in, The first frequency components, The first frequency components, represents the frequency index, Indicates the sampling points, Indicates the signal length, represents the voltage signal after windowing, represents the current signal after windowing, Indicates The exponential function with base , represents the imaginary unit, Represents pi.

7. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The analyzing the transient response of the frequency domain data includes: Extracting frequency points of interest of the harmonic components; Determining the complex spectrum value of the frequency point of interest; constructing an interest spectrum of the frequency domain data according to the interest frequency points and the complex spectrum values; Performing an inverse time domain transformation on the spectrum of interest to obtain a complex sequence; A real number portion of the complex number sequence is extracted, and a transient response of the frequency domain data is determined based on the real number portion.

8. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The analyzing the electric vehicle type and the load type of the charging circuit according to the impedance value and the characteristic parameter includes: Acquiring electric vehicle data and electrical characteristic data corresponding to the charging line; Building a type analysis database of the charging line based on the electric vehicle data and the electrical characteristic data; Calculating the automobile category similarity and the load category similarity in the type analysis database according to the impedance value and the characteristic parameter; The electric vehicle type and the load type of the charging line are determined according to the vehicle type similarity and the load type similarity.

9. The charging pile circuit detection method for automatically identifying electric vehicles and loads according to claim 1, characterized in that: The analyzing the load state of the charging circuit according to the electric vehicle type and the load type includes: Extracting electric vehicle characteristics and load characteristics of the electric vehicle corresponding to the charging line according to the electric vehicle type and the load type; Calculating an instantaneous power demand curve of the electric vehicle according to the electric vehicle characteristics and the load characteristics; identifying a peak power of the instantaneous power demand curve; Calculating a real-time load rate of the charging circuit according to the peak power and a corresponding instantaneous response of the charging circuit; The load state of the charging circuit is determined according to the real-time load rate.

10. A charging pile circuit detection system for automatically identifying electric vehicles and loads, characterized in that: The system comprises: A signal detection module is used to construct a high-frequency signal injection unit and a signal acquisition unit of the charging pile, determine the signal parameters of the high-frequency signal injection unit, and based on the signal parameters, inject a specific high-frequency detection signal into the charging line corresponding to the charging pile through the high-frequency signal injection unit. Based on the high-frequency detection signal, the signal acquisition unit collects the voltage signal and current signal of the charging line; an impedance value analysis module, configured to perform time domain analysis on the voltage signal and the current signal to obtain an effective voltage value and an effective current value, and calculate the impedance value of the charging circuit based on the effective voltage value and the effective current value; an electrical parameter analysis module, configured to perform frequency domain transformation on the voltage signal and the current signal to obtain frequency domain data, analyze harmonic components of the frequency domain data, determine a transient response of the frequency domain data based on the harmonic components, and extract characteristic parameters of the transient response; a state detection module, configured to analyze the electric vehicle type and load type of the charging circuit according to the impedance value and the characteristic parameter, analyze the load state of the charging circuit according to the electric vehicle type and the load type, identify abnormal states of the load state, establish an abnormal alarm mechanism for the abnormal state, and determine abnormal adjustment parameters of the charging pile based on the abnormal state; A detection scheme generating module is used to determine a circuit detection scheme for the charging pile based on the load state, the abnormal alarm mechanism and the abnormal adjustment parameter.

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