Energy recovery type intelligent charging pile

Abstract

The invention provides an energy recovery type intelligent charging pile. The energy recovery type intelligent charging pile comprises a charging pile body, a charging module, a control module, an insulation monitoring module, a fault early warning module, an energy recovery module and an active repairing module. The insulation resistance value of the charging cable is monitored in real time through the insulation monitoring module; a multi-stage processing mechanism including early warning, power reduction charging and circuit breaking is triggered through a fault early warning module according to the comparison data; when the fault triggering data comprises triggering power reduction or circuit breaking, residual electric energy in a charging loop is stored through an energy recovery module; the active repair module generates a high-voltage pulse with a preset peak frequency by using the electric energy stored by the energy recovery module, and performs physical repair on an insulation damaged part of the charging cable. Through real-time sensing of the insulation monitoring module, intelligent decision making of the fault early warning module, closed-loop management of the energy recovery module and physical intervention of the active repair module, early warning and active repair are carried out on the insulation fault of the charging cable, and the usability of the charging pile is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of charging piles, and particularly to an energy recovery type intelligent charging pile. Background Art

[0002] With the rapid development of the global new energy vehicle industry, electric vehicles have gradually become the mainstream means of transportation with their environmental protection and high-efficiency advantages, and the construction of supporting charging infrastructure has also entered a stage of rapid development. As a key device connecting the power grid and electric vehicles, the safety, reliability, and intelligent level of charging piles directly affect the stability of the charging process and the user experience. In the prior art, the functions of charging piles mainly focus on power conversion and transmission control. Although some high-end products have introduced energy recovery technology to improve energy utilization efficiency, there are still significant technical bottlenecks in the field of safety monitoring of charging cable circuits.

[0003] During the charging process, factors such as the aging of the insulation layer of the charging cable due to long-term use, external mechanical damage, and changes in environmental humidity may cause a decline in insulation performance or even insulation failure, thereby causing safety hazards such as electric leakage and short circuit. At present, traditional charging piles generally adopt a passive safety protection strategy, and only trigger power-off protection when the detected leakage current exceeds the threshold. This post-treatment method has obvious defects: on the one hand, it is impossible to monitor the deterioration trend of insulation performance in real time and give early warnings before insulation failure, making it difficult to avoid accidents; on the other hand, when insulation failure occurs, the charging pile lacks the ability to actively repair and can only be processed by manually replacing the cable, resulting in high maintenance costs and long downtime, seriously affecting the availability of the charging pile. Summary of the Invention

[0004] In view of this, the present invention proposes an energy recovery type intelligent charging pile to solve the technical problem that the existing charging piles cannot give early warnings and actively repair insulation failures of charging cables, resulting in low availability of charging piles.

[0005] The technical solution of the present invention is realized as follows:

[0006] An energy recovery type intelligent charging pile includes: a charging pile body, and a charging module, a control module, an insulation monitoring module, a fault warning module, an energy recovery module, and an active repair module provided on the charging pile body; the charging module is connected to a device to be charged through a charging cable;

[0007] The insulation monitoring module is used to continuously monitor the insulation resistance value of the charging cable and compare it with a preset multi-level threshold to generate comparison data;

[0008] The fault warning module is used to trigger a multi-level processing mechanism including warning, reducing power charging, and opening the circuit according to the comparison data;

[0009] The energy recovery module is used to store the remaining electric energy in the charging circuit when the fault trigger data includes triggering power reduction or open circuit.

[0010] The active repair module is used to generate high-voltage pulses with a preset peak frequency by using the electric energy stored in the energy recovery module, and physically repair the insulation damage part of the charging cable.

[0011] Optionally, the insulation monitoring module includes a distributed insulation detection unit, a dynamic threshold adjustment unit, and a comparison unit;

[0012] The distributed insulation detection unit includes a plurality of insulation detection sensors, which are arranged at intervals on the surface of the outer insulation layer of the charging cable in a spiral winding manner, and are used to synchronously detect the temperature, humidity, and insulation resistance value at each position along the axial direction of the charging cable, and generate temperature data, humidity data, and insulation resistance value;

[0013] The dynamic threshold adjustment unit is used to dynamically correct the threshold by using the temperature data, the humidity data, and the historical insulation degradation curve through an adaptive algorithm, and generate a target multi-level threshold;

[0014] The comparison unit is used to compare the insulation resistance value with the target multi-level threshold to generate comparison data.

[0015] Optionally, the distributed insulation detection unit further includes:

[0016] The sensor self-calibration module is used to substitute the temperature data, the humidity data, and the insulation resistance value into a preset resistance compensation formula, calculate the insulation resistance correction value, and send it to the comparison unit;

[0017] The high-frequency pulse injection module is used to inject a non-destructive high-voltage pulse signal into the charging cable, calculate the internal partial discharge amount of the cable by detecting the pulse attenuation characteristic, and send the partial discharge amount as an auxiliary parameter to the dynamic threshold adjustment unit.

[0018] Optionally, the execution steps of the dynamic threshold adjustment unit are:

[0019] Filter and denoise the temperature data and the humidity data to generate target temperature data and target humidity data;

[0020] Calculate the comprehensive influence factor of environmental parameters by using the target temperature data, the target humidity data, and the preset upper limit values of temperature and humidity;

[0021] Predict the baseline threshold at the current moment by using the historical insulation degradation curve;

[0022] Modify the baseline threshold using the comprehensive influence factor of the environmental parameters to generate a target multi-level threshold.

[0023] Optionally, the target multi-level threshold includes a normal threshold, a warning threshold, and a fault threshold; the execution steps of the fault warning module are as follows:

[0024] When the comparison data shows that the insulation resistance value is lower than the normal threshold and higher than the warning threshold, trigger the warning mechanism and send a warning signal through the acoustic-optic alarm device;

[0025] When the comparison data shows that the insulation resistance value is lower than the warning threshold and higher than the fault threshold, trigger the power reduction charging mechanism, and linearly reduce the charging power to a preset range of the rated power according to the deviation ratio between the insulation resistance value and the warning threshold;

[0026] When the comparison data shows that the insulation resistance value is lower than the fault threshold, trigger the open circuit mechanism, cut off the charging circuit, and send a fault message to the management terminal through the wireless communication module.

[0027] Optionally, the energy recovery module includes a bidirectional DC converter, a supercapacitor bank, and a charge and discharge control unit;

[0028] The bidirectional DC converter is connected to the charging circuit and the supercapacitor bank, and is used to switch to the electric energy recovery mode when the power is reduced or the circuit is opened;

[0029] The supercapacitor bank is used to store the remaining electric energy in the charging circuit;

[0030] The charge and discharge control unit is used to trigger overload protection and stop recovery when the remaining electric energy is greater than or equal to the preset rated capacity.

[0031] Optionally, the execution steps of the active repair module are as follows:

[0032] Based on the broken location algorithm of the traveling wave ranging principle, calculate the insulation break location through the pulse reflection time difference;

[0033] Generate a high-voltage pulse with a preset peak frequency using the electric energy stored in the energy recovery module, and physically repair the insulation break part of the charging cable;

[0034] During the repair process, monitor the pulse attenuation rate in real time, and determine that the repair is completed when the pulse attenuation rate drops by greater than or equal to the preset drop threshold.

[0035] Optionally, the active repair module includes a high-voltage pulse generator, a repair effect evaluation unit, and a pulse application electrode, and the pulse application electrode wraps the insulation break part of the charging cable in a ring structure;

[0036] The high-voltage pulse generator is used to output square pulses and transmit them to the pulse application electrode;

[0037] The repair effect evaluation unit is used to redetect the insulation resistance value after the pulse is applied. If the new insulation resistance value is less than the preset recovery threshold, secondary repair is triggered.

[0038] Optionally, the execution steps of the repair effect evaluation unit are as follows:

[0039] Redetect the insulation resistance value after the pulse is applied and calculate the corresponding resistance recovery rate;

[0040] When the resistance recovery rate is less than the preset recovery rate threshold, increase the pulse voltage by a corresponding preset multiple of the current voltage value for secondary repair;

[0041] When the resistance recovery rate corresponding to the secondary repair is less than the preset recovery rate threshold, mark the insulation damage part of the charging cable as irreparable and notify the management terminal.

[0042] Optionally, the control module adopts a dual-redundancy control system, including a main control unit and a standby control unit. When the main control unit fails, the standby control unit automatically takes over the control within a preset time to ensure the normal operation of the charging pile.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] An energy recovery type intelligent charging pile of the present invention includes a charging pile body and a charging module, a control module, an insulation monitoring module, a fault warning module, an energy recovery module, and an active repair module provided on the charging pile body. The insulation monitoring module can timely detect potential insulation degradation problems by real-time monitoring of the insulation resistance value of the charging cable, and avoid sudden failures caused by the decline of insulation performance. By setting a multi-level threshold comparison mode, hierarchical management can be realized, the judgment accuracy can be improved, and the situations of false alarms or missed alarms can be reduced. The fault warning module is used to adopt different levels of processing mechanisms according to different states of the insulation resistance value, effectively reducing potential safety hazards. The energy recovery module is used to recover the residual electric energy in the charging circuit to the super capacitor bank when a power reduction or open circuit event occurs, avoiding energy waste caused by direct discharge. The active repair module is used to generate high-voltage pulses using the electric energy stored in the energy recovery module after determining the insulation damage position, and perform physical repairs such as partial discharge or thermal effect treatment on the insulation defect part to promote the recovery of the insulation material and achieve autonomous repair. The intelligent level, safety, and usability of the charging pile are improved. Description of the Drawings

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for description in the embodiments. Obviously, the drawings in the following description are only the preferred embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0046] Figure 1 Structural schematic diagram of an energy recovery type intelligent charging pile of the present invention;

[0047] Figure 2 Structural schematic diagram of an insulation monitoring module in an energy recovery type intelligent charging pile of the present invention;

[0048] Figure 3 Structural schematic diagram of an energy recovery module in an energy recovery type intelligent charging pile of the present invention;

[0049] Figure 4 Structural schematic diagram of an active repair module in an energy recovery type intelligent charging pile of the present invention;

[0050] Figure 5 Structural schematic diagram of a control module in an energy recovery type intelligent charging pile of the present invention. Detailed implementation manners

[0051] See Figure 1 , an energy recovery type intelligent charging pile, including: a charging pile body and a charging module, a control module, an insulation monitoring module, a fault warning module, an energy recovery module, and an active repair module provided on the charging pile body; the charging module is connected to the device to be charged through a charging cable;

[0052] The insulation monitoring module is used to monitor the insulation resistance value of the charging cable in real time, compare it with a preset multi-level threshold, and generate comparison data;

[0053] The fault warning module is used to trigger a multi-level processing mechanism including warning, reducing power charging, and open circuit according to the comparison data;

[0054] The energy recovery module is used to store the remaining electric energy in the charging circuit when the fault trigger data includes triggering power reduction or open circuit;

[0055] The active repair module is used to generate a high-voltage pulse with a preset peak frequency by using the electric energy stored in the energy recovery module, and physically repair the insulation damaged part of the charging cable.

[0056] In the embodiments of the present invention, the charging pile body adopts a metal shell with an IP55 protection level, and the size is 800mm×600mm×1800mm. The following modules are integrated inside:

[0057] Charging Module (Located at the bottom): It includes an AC / DC or DC / DC power conversion unit, supporting a maximum charging power of 120kW (DC fast charging) and 7kW (AC slow charging);

[0058] Control Module (Industrial computer in the middle): Adopts an Advantech UNO-3082G industrial computer, equipped with an Intel Atom E3845 processor (1.91GHz), and integrates a dual-redundant control unit (main unit: STM32H750; backup unit: NXP i.MX 8M);

[0059] Insulation Monitoring Module, Fault Warning Module (Top control cabinet): Installed through a standardized DIN rail;

[0060] Energy Recovery Module (Cabinet on the left): Includes a supercapacitor bank and a bidirectional DC-DC converter;

[0061] Active Repair Module (Cabinet on the right): Includes a high-voltage pulse generator and a pulse application electrode.

[0062] Specifically, the hardware configuration of the charging module includes: (1) DC fast charging: Adopts a three-phase PFC + full-bridge LLC resonant converter, with an input voltage of AC = 380V ± 15%, an output voltage of DC = 200V - 1000V, and an efficiency of ≥96%; AC slow charging: Adopts an on-board charger (OBC), with an input of AC = 220V / 32A and an output of DC = 400V / 16A; (2) Charging interface: Compatible with GB / T20234-2023 DC / AC charging interfaces, with a built-in CC / CP signal detection circuit; Safety protection: Integrates a 500A high-voltage DC relay (Hongfa HF3000), with a response time of ≤10ms. The charging module communicates with the control module through a CAN bus (ISO 11898-2 standard), reporting the charging voltage and current in real time; Receiving the power adjustment instruction (0-10V analog signal) from the control module, supporting 0-100% power linear adjustment.

[0063] The insulation monitoring module detects the insulation resistance value, temperature and humidity of the charging cable in real time through distributed sensors to generate comparison data; the dynamic threshold adjustment unit combines the temperature and humidity data and the historical degradation curve to correct the threshold to adapt to environmental changes. The fault warning module triggers a three-level response based on the comparison data: warning (sound and light alarm), power reduction charging (linear power reduction according to the deviation ratio) and circuit breaking (cutting off the circuit and notifying the management terminal). When the energy recovery module reduces power or breaks the circuit, the remaining electric energy is stored in the supercapacitor group through a bidirectional DC converter; the charge and discharge control unit triggers overload protection when the energy storage exceeds the limit. The active repair module uses the recovered electric energy to generate a high-voltage pulse with a preset peak frequency (such as 1-5kV, 1-10kHz), and physically repairs the damaged insulation part through the ring electrode; the repair effect evaluation unit determines the completion of the repair through the pulse attenuation rate and the insulation resistance recovery rate. The control module ensures that the equipment automatically switches and maintains operation in the event of a fault through a dual redundant control system (active and standby control unit).

[0064] Further, see Figure 2 ,The insulation monitoring module includes a distributed insulation detection unit, a dynamic threshold adjustment unit and a comparison unit;

[0065] The distributed insulation detection unit includes a plurality of insulation detection sensors, which are arranged at intervals on the surface of the outer insulation layer of the charging cable in a spiral winding manner, and are used to synchronously detect the temperature, humidity and insulation resistance value of each axial position of the charging cable, and generate temperature data, humidity data and insulation resistance value;

[0066] A dynamic threshold adjustment unit, used to dynamically modify the threshold using temperature data, humidity data and historical insulation degradation curves through an adaptive algorithm to generate a target multi-level threshold;

[0067] The comparison unit is used to compare the insulation resistance value with the target multi-level threshold value to generate comparison data.

[0068] In the embodiment of the present invention, the distributed insulation detection unit includes a plurality of insulation detection sensors, and the insulation detection sensors are SICK LFP-100 composite sensors. Eight SICK LFP-100 composite sensors (model: 1051234) are used, and each sensor integrates: an NTC temperature sensor (accuracy ±0.3°C, temperature measurement range -40°C to 85°C, response time ≤10 s); a capacitive humidity sensor (accuracy ±2%RH, measurement range 0-100%RH, dew point compensation algorithm); a four-wire insulation resistance tester (measurement principle: voltammetry, measurement range 0.1 MΩ - 1 GΩ, resolution 0.1 MΩ, test voltage 500 VDC). The sensors are arranged on the outer insulation surface of the charging cable (length 5 m, outer diameter 20 mm) at intervals of 50 cm in a spiral winding manner. The axial distance between adjacent sensors covers the entire length of the cable, and the helix angle is 30°, ensuring no dead angle monitoring in the circumferential direction of 360°. In the signal acquisition process, the original analog signal is converted into a digital signal by a 24-bit ADC (ADS1256, signal-to-noise ratio 123 dB) and transmitted to the dynamic threshold adjustment unit through a shielded twisted pair cable (distributed capacitance ≤50 pF / m), and the sampling frequency is 10 Hz. The temperature / humidity sensor is connected to a standard calibration chamber (accuracy ±0.1°C / ±1%RH) to correct the zero drift; the insulation resistance sensor is connected to a 10 MΩ ±0.1% standard resistor to calibrate the gain error of the measurement circuit, and the accuracy is improved to ±1.5% after calibration.

[0069] Filter and denoise the temperature data and humidity data to generate target temperature data and target humidity data; calculate the comprehensive influence factor of environmental parameters using the target temperature data, target humidity data, and preset upper limit values of temperature and humidity; predict the baseline threshold at the current moment using the historical insulation degradation curve; correct the baseline threshold using the comprehensive influence factor of environmental parameters to generate the target multi-level threshold.

[0070] The comparison unit compares the insulation resistance value generated by the distributed insulation detection unit with the target multi-level threshold generated by the dynamic threshold adjustment unit in real time to generate comparison data. The target multi-level threshold includes a normal threshold, a warning threshold, and a fault threshold, which are used to distinguish different levels of insulation states (such as healthy, potential risk, and fault).

[0071] Furthermore, the distributed insulation detection unit further includes:

[0072] A sensor self-calibration module, which is used to substitute the temperature data, humidity data, and insulation resistance value into a preset resistance compensation formula, calculate the insulation resistance correction value, and send it to the comparison unit;

[0073] A high-frequency pulse injection module, which is used to inject a non-destructive high-voltage pulse signal into the charging cable, calculate the internal partial discharge amount of the cable by detecting the pulse attenuation characteristics, and send the partial discharge amount as an auxiliary parameter to the dynamic threshold adjustment unit.

[0074] In the embodiment of the present invention, the sensor self-calibration module corrects the original insulation resistance value through a preset resistance compensation formula to eliminate the interference of environmental temperature and humidity on the measurement result. The core formula, i.e., the preset resistance compensation formula, is as follows:

[0075] R corrected =R measured ·(1 + l1·(T - T0) + l2·(H - H0));

[0076] Wherein, R corrected is the insulation resistance correction value; R measured is the original measurement value of the sensor; R is the temperature detected in real time; H is the humidity detected in real time; T0 is the temperature under standard calibration conditions; H0 is the humidity under standard calibration conditions; k1 is the influence coefficient of temperature on the insulation resistance; k2 is the influence coefficient of humidity on the insulation resistance. The sensor self-calibration module receives the temperature data, humidity data and insulation resistance value from the distributed insulation detection unit, and the sampling frequency is 1Hz. Based on the ARM Cortex-M4 chip (such as STM32F407), the compensation algorithm is run, and 256KB of memory is reserved to store the calibration coefficient and historical data. The corrected insulation resistance value R corrected is transmitted to the comparison unit through the SPI bus.

[0077] The high-frequency pulse injection module injects a non-destructive high-voltage pulse signal (such as 500Vpp, 100kHz square wave) into the charging cable, detects the attenuation characteristics of the pulse in the cable, and indirectly calculates the partial discharge amount (ΔQ). The core steps are as follows:

[0078] (1) Pulse injection: Generate a pulse signal through a high-voltage signal generator (such as Tektronix AWG7000B) and inject it into the cable through an impedance matching transformer (1:1000).

[0079] (2) Attenuation detection: Install a coupling capacitor (100pF) and an impedance converter (50Ω) at the end of the cable, and collect the pulse reflection signal (oscilloscope sampling rate ≥ 1GSa / s).

[0080] (3) Partial discharge amount calculation: Through the linear relationship model between the pulse attenuation amplitude and the partial discharge energy (ΔQ = α·ΔA + β), where α and β are experimental calibration parameters (such as α = 0.8pC / V, β = 0.2pC); A is the amplitude of the pulse signal.

[0081] Furthermore, the execution steps of the dynamic threshold adjustment unit are as follows:

[0082] Filter and denoise the temperature data and humidity data to generate target temperature data and target humidity data;

[0083] Calculate the comprehensive influence factor of environmental parameters using the target temperature data, target humidity data, and preset upper limit values of temperature and humidity;

[0084] Predict the baseline threshold at the current moment using the historical insulation degradation curve;

[0085] Modify the baseline threshold using the comprehensive influence factor of environmental parameters to generate the target multi-level threshold.

[0086] In the embodiment of the present invention, in the operating environment of the charging cable, the original data of the temperature sensor (such as DS18B20) and humidity sensor (such as SHT30) are vulnerable to electromagnetic interference (EMI) and signal transmission delay, resulting in high-frequency noises such as ±2°C temperature fluctuations and ±5%RH humidity jumps. It is necessary to improve the data reliability through a filtering algorithm. The moving average filter is used to denoise the temperature / humidity data to eliminate sensor noise and instantaneous fluctuations. The moving average filter formula:

[0087]

[0088] where, T filtered (t) is the target temperature data after moving average filtering, eliminating noise and fluctuations, and its value at time t; T raw (t - i) is the sampled value of the original temperature data at time (t - i) (i = 0, 1,..., N - 1), including sensor noise and instantaneous fluctuations; H filtered (t) is the target humidity data after moving average filtering, eliminating noise and fluctuations, and its value at time t; H raw (t - i) is the sampled value of the original humidity data at time (t - i) (i = 0, 1,..., N - 1), including sensor noise and instantaneous fluctuations; N is the length of the moving window (preferably 5 sampling points), that is, the number of consecutive sampling points used to calculate the average value (N historical data, including the data at the current moment t, a total of N points); t is the time variable, representing the current moment, and is used to index the timestamp of the data. The specific filtering and denoising process is as follows: First, receive the original temperature and humidity data (sampling frequency 1Hz) of the distributed insulation detection unit. Then, run the filtering algorithm based on the ARM Cortex-M4 chip (such as STM32F407). Then, transmit the target temperature data T filtered and the target humidity data H filtered to the next step through the SPI bus.

[0089] Combine the target temperature data T filtered and the target humidity data H filtered and the preset upper limit values of temperature and humidity (T max = 40°C, H max= 80% RH (this value is obtained from experiments), calculate the comprehensive influence factor K of environmental parameters env , and its calculation formula is:

[0090]

[0091] Among them, K env is the comprehensive influence factor of environmental parameters; T filtered is the target temperature data; H filtered is the target humidity data; T max is the preset temperature upper limit value; H max is the preset humidity upper limit value; α is the temperature weight data; β is the humidity weight data. The calculation process of the comprehensive influence factor of environmental parameters is as follows: receive the filtered target temperature data T filtered and the target humidity data H filtered , perform real-time calculation through FPGA (such as Xilinx Artix-7), and send K env to the baseline threshold prediction module. The baseline threshold prediction module uses the historical insulation degradation curve to predict the baseline threshold at the current moment. Specifically, the technical principle of the baseline threshold prediction module is:

[0092] Based on the historical insulation degradation curve (obtained through laboratory accelerated aging experiments), use a linear regression model to predict the baseline threshold R baseline at the current moment. The model formula is:

[0093] R baseline (t) = a·t + b;

[0094] Among them, a is the degradation rate (unit: ΜΩ / h); t is the time; b is the initial threshold. The specific prediction process is as follows: call the historical insulation degradation curve stored in the cloud (such as R = 1000 ΜΩ when t = 0, R = 800 ΜΩ when t = 100 h); run the regression algorithm through the cloud server, reserve 2 GB of memory for storing historical data, and predict the baseline threshold R baseline at the current moment, and send it to the correction module.

[0095] The correction module uses the comprehensive influence factor of environmental parameters to correct the baseline threshold to obtain the target multi-level threshold. The correction formula used is:

[0096] R threshold = R baseline ·(1 - K env );

[0097] Among them, R threshold is the target multi-level threshold, which is used to divide the multi-level warning range according to the corrected threshold (such as normal / warning / fault); R baseline is the baseline threshold; K envis the comprehensive influence factor of environmental parameters. The specific execution process is as follows: Receive the baseline threshold and the comprehensive influence factor of environmental parameters, and calculate the target multi-level threshold based on the correction algorithm running on the ARM Cortex-M4 chip. Then, transmit the target multi-level threshold to the comparison unit through the CAN bus.

[0098] Furthermore, the target multi-level threshold includes a normal threshold, a warning threshold, and a fault threshold; the execution steps of the fault warning module are as follows:

[0099] When the comparison data shows that the insulation resistance value is lower than the normal threshold but higher than the warning threshold, trigger the warning mechanism and send a warning signal through the acoustic-optic alarm device;

[0100] When the comparison data shows that the insulation resistance value is lower than the warning threshold but higher than the fault threshold, trigger the power reduction charging mechanism, and linearly reduce the charging power to a preset range of the rated power according to the deviation ratio between the insulation resistance value and the warning threshold;

[0101] When the comparison data shows that the insulation resistance value is lower than the fault threshold, trigger the open circuit mechanism, cut off the charging circuit, and send a fault message to the management terminal through the wireless communication module.

[0102] In the embodiment of the present invention, the fault warning module is a key control unit in the distributed insulation detection system, which is used to compare the insulation resistance value output by the comparison unit with the dynamically generated target multi-level threshold and execute different levels of response mechanisms. The target multi-level threshold includes: the normal threshold R normal indicating that the cable insulation state is good; the warning threshold R warn indicating that the insulation performance has declined but has not reached a dangerous level; the fault threshold R fault indicating that the cable has serious insulation defects and needs to be processed immediately. This module realizes hierarchical management through three types of response mechanisms: (1) Warning mechanism: When the insulation resistance value is lower than the normal threshold but still higher than the warning threshold, start the acoustic-optic alarm; (2) Power reduction charging mechanism: When the insulation resistance value is lower than the warning threshold but still higher than the fault threshold, reduce the charging power in proportion; (3) Open circuit mechanism: When the insulation resistance value is lower than the fault threshold, cut off the charging circuit and send a fault message to the management terminal.

[0103] If the comparison data shows that the insulation resistance value is lower than the normal threshold but higher than the warning threshold, it is determined as mild insulation deterioration, trigger the warning mechanism, and control the acoustic-optic alarm device to emit a flashing yellow warning light and a buzzer prompt to remind the on-site personnel to pay attention to the cable operation status. The specific hardware implementation process is to use a PLC controller (such as Siemens S7-1200) to receive the comparison result; control the LED indicator light and the buzzer drive circuit (relay module) through the digital output port; set the alarm duration to 5 minutes or reset it manually.

[0104] If the comparison data shows that the insulation resistance value is lower than the warning threshold but higher than the fault threshold, it is determined as moderate insulation deterioration, and the power reduction mechanism is triggered. According to the deviation degree between the insulation resistance value and the warning threshold, the charging power is adjusted using a linear relationship. The formula is as follows:

[0105]

[0106] Where, P adjusted is the adjusted power value; P rated is the rated power of the charging device (such as 120kW); R warn is the warning threshold; R measured is; R fault is the fault threshold; γ is the power attenuation coefficient (the recommended value is 0.6 - 0.8 to prevent excessive frequency reduction from affecting efficiency). The specific hardware implementation process is as follows: receive the comparison result through the CAN bus; calculate the adjusted power value using the BMS (Battery Management System) or the main control chip of the charging pile (such as TI TMS320F280049); send a power setting instruction to the communication interface of the charging pile (following the GB / T 27930 protocol).

[0107] If the comparison data shows that the insulation resistance value is lower than the fault threshold, it is determined as a serious insulation fault, and the open - circuit protection is triggered to control the contactor to disconnect the charging circuit to prevent the risk of high - voltage breakdown or fire; send the fault information (including timestamp, device ID, insulation resistance value, etc.) to the management terminal through the wireless communication module (such as 4G DTU or NB - IoT module). The specific hardware implementation process is as follows: use a high - voltage DC contactor (such as Omron G9EB), which supports a DC 1000V / 100A load; configure a remote communication module (such as Huawei ME909s - 821) to connect to the cloud platform; the fault information format adopts the JSON structure.

[0108] Furthermore, referring to Figure 3 , the energy recovery module includes a bidirectional DC converter, a supercapacitor bank, and a charge - discharge control unit;

[0109] The bidirectional DC converter connects the charging circuit and the supercapacitor bank, and is used to switch to the electric energy recovery mode during power reduction or open - circuit;

[0110] The supercapacitor bank is used to store the remaining electric energy in the charging circuit;

[0111] The charge - discharge control unit is used to trigger the overload protection and stop the recovery when the remaining electric energy is greater than or equal to the preset rated capacity.

[0112] In the embodiments of the present invention, the energy recovery module is a key component in the present invention for improving the energy efficiency of the charging system and reducing energy waste, especially playing a role when reducing power charging or triggering open circuit protection. This module recovers the unused electrical energy in the charging circuit and temporarily stores it in a high-power density energy storage device for subsequent use or safe release. The energy recovery module includes the following three core parts: (1) Bidirectional DC / DC Converter: responsible for achieving voltage matching and energy flow control under different working modes; (2) Supercapacitor Bank: as a high-efficiency and fast-response energy storage element, used to absorb and release transient energy; (3) Charging and Discharging Control Unit: monitors the energy storage status in real time and implements overload protection strategies.

[0113] Under normal operating conditions, the bidirectional DC / DC converter is in a standby mode; when the system detects a reduction in power charging or an open circuit event, it automatically switches to the energy recovery mode and transfers the unused energy in the charging circuit to the supercapacitor bank. The bidirectional DC / DC converter adopts a half-bridge bidirectional DC / DC converter structure, with high efficiency (≥90%) and low loss (<5% full-load loss) characteristics, supports a wide input voltage range (300V - 800V), and the output terminal is connected to the supercapacitor bank (rated voltage 750V). When the fault warning module issues a "power reduction" signal, recovery mode A (low-speed recovery) is started; when an "open circuit" signal is issued, recovery mode B (high-speed recovery) is started to ensure rapid absorption of residual energy. Among them, the switching threshold voltage is 650V; the maximum recovery current is 20A; the recovery efficiency is 0.92.

[0114] Select supercapacitor monomers with a double-layer electrode structure (such as Maxwell BMOD0063), with a monomer capacity of 3400F and a rated voltage of 2.7V. After series combination, a high-voltage energy storage array is formed. Configure a forced air cooling system (fan power 10W) to ensure that the working temperature is maintained between -20°C and +65°C, extending the service life. The charging and discharging control unit monitors the voltage and energy storage status of the supercapacitor bank in real time, determines whether the preset rated capacity is reached, and triggers a protection action in case of overload.

[0115] Assume the current energy storage capacity is E current and the preset rated capacity is E threshold Then the control rules are as follows:

[0116] If E current < E threshold : Continue to allow energy recovery;

[0117] If E current≥E threshold : Trigger the overload protection, close the recovery channel and activate the discharge path.

[0118] The energy storage capacity calculation formula is:

[0119]

[0120] The overload determination condition is:

[0121] E current ≥E threshold ;

[0122] Wherein, E current is the current energy storage capacity, with the unit of joule (J); E threshold is the preset rated capacity; C total is the total capacitance value of the supercapacitor bank, with the unit of farad (F); V cap is the current terminal voltage of the supercapacitor bank, with the unit of volt (V), and it is one of the key parameters to measure the current energy state of the supercapacitor bank.

[0123] When E current reaches or exceeds E threshold the system will trigger the overload protection mechanism, close the energy recovery channel and activate the discharge path to prevent overcharging of the supercapacitor bank and generate safety risks.

[0124] Furthermore, the execution steps of the active repair module are:

[0125] Based on the traveling wave ranging principle, the insulation breakage location algorithm calculates the insulation breakage location through the pulse reflection time difference;

[0126] Generate high-voltage pulses with a preset peak frequency using the electric energy stored in the energy recovery module, and physically repair the insulation breakage part of the charging cable;

[0127] During the repair process, the pulse decay rate is monitored in real time. When the pulse decay rate drops greater than or equal to the preset decay threshold, it is determined that the repair is completed.

[0128] In the embodiment of the present invention, the active repair module is the key component in the present invention for realizing automatic positioning and physical repair of cable insulation defects. This module can complete accurate positioning and physical repair of the insulation breakage part of the charging cable without interrupting the system operation by integrating traveling wave ranging technology, high-voltage pulse generating device and real-time monitoring mechanism. Utilizing the propagation characteristics of traveling waves in the cable, when there is an insulation breakage in the cable, the injected high-voltage pulse will generate a reflected wave at the breakage point. By measuring the time difference (Δt) between the transmitted wave and the reflected wave, the distance L defect from the breakage point to the starting point can be calculated, and the corresponding positioning formula is:

[0129]

[0130] Among them, L defect is the distance from the break point to the starting point; v is the propagation speed of electromagnetic waves in the cable (usually 0.65 to 0.85 times the speed of light, depending on the cable material); Δt is the arrival time difference between the transmitted wave and the reflected wave (unit: second); the denominator "2" represents the round-trip of the signal. The specific hardware implementation process is as follows: Use an FPGA chip (such as Intel Cyclone V) as the core processing unit; configure a high-speed sampling ADC (sampling rate ≥ 1 GSPS) to capture weak reflection signals; injection pulse frequency range: 1 MHz to 10 MHz, peak voltage ≤ 2 kV, collect the propagation speed and the arrival time difference between the transmitted wave and the reflected wave, and calculate the insulation break position.

[0131] After locating the insulation break position, use the electric energy stored in the energy recovery module to generate high-voltage pulses with specific peak voltage and frequency through a boost converter and a pulse-forming network (PFN), which act on the insulation break part of the cable to stimulate partial discharge or thermal effect, and promote the re-fusion or filling of cracks in the insulation material. Among them, the high-voltage pulse parameters are set as follows: (1) Peak voltage: V p = 3 kV to 5 kV; (2) Pulse width: T w = 1 μs to 10 μs; (3) Repetition frequency: f p = 1 kHz to 10 kHz; (4) Total repair cycle: not exceeding 3 minutes. The specific hardware implementation process is as follows: Use IGBT power devices (such as Infineon FF600R12ME4) to build a full-bridge inverter circuit; the turns ratio of the boost transformer is set to 1:100; pulse control adopts a PWM modulation strategy, and a drive signal is generated by a DSP controller (such as TI TMS320F28379D); the required electric energy is provided by the supercapacitor bank in the energy recovery module. For example: Example: When the voltage of the supercapacitor bank V cap = 700 V, set the boost to V p = 4.2 V, and apply 100 pulses, each pulse lasting for 5 μs, with an interval of 0.5 ms. The total repair time is about 50 seconds.

[0132] During the application of the high-voltage pulse, by detecting the current response in the circuit, analyzing the change trend of the pulse amplitude over time, and calculating the pulse decay rate δ, the insulation repair effect can be judged. The calculation formula for the pulse decay rate is:

[0133]

[0134] Among them, δ(t) is the current pulse decay rate; A0 is the initial pulse amplitude; A tis the amplitude after the t-th pulse. If in three consecutive measurements, the decrease in the pulse decay rate is greater than or equal to the preset threshold δ threshold , that is, it satisfies:

[0135] δ(t + 1) - δ(t) ≥ δ threshold ;

[0136] then it is considered that the insulating material has recovered and the repair is completed. Among them, δ threshold = 0.15, that is, when the decay rate decreases by more than 15% is regarded as the repair completed; the sampling frequency is 10 MHz; the monitoring circuit uses a Hall current sensor (such as LEM LTS25-NP).

[0137] Furthermore, referring to Figure 4 , the active repair module includes a high-voltage pulse generator, a repair effect evaluation unit, and a pulse application electrode. The pulse application electrode wraps the insulation damaged part of the charging cable in a ring structure;

[0138] The high-voltage pulse generator is used to output square pulses and transmit them to the pulse application electrode;

[0139] The repair effect evaluation unit is used to re-detect the insulation resistance value after the pulse is applied. If the new insulation resistance value is less than the preset recovery threshold, secondary repair is triggered.

[0140] In the embodiment of the present invention, the active repair module is the core component in the present invention for physically repairing the insulation damaged part of the charging cable. By integrating a high-voltage pulse generator, a ring-shaped pulse application electrode, and a repair effect evaluation unit, this module can complete the automatic repair of insulation defects without disassembling the cable. Its main components include: the High-Voltage Pulse Generator is used to generate square high-voltage pulses with specific peak voltages and durations; the Pulse Application Electrode is used to wrap the insulation damaged part of the cable in a ring structure to ensure uniform pulse application; the Repair Effect EvaluationUnit is used to re-detect the insulation resistance value after the pulse is applied and determine whether secondary repair is required.

[0141] Specifically, the high-voltage pulse generator is used to generate and output square high-voltage pulses, which act on the insulation damaged part of the cable to stimulate partial discharge or thermal effects and promote the recovery of the insulating material. The output parameters of the high-voltage pulse generator are set as follows: (1) Pulse type: square wave pulse; (2) Peak voltage range: V pulse = 3 kV to 6 kV; (3) Pulse width: T width = 1 μs to 10 μs; (4) Repetition frequency: f repeat= 1 kHz to 5 kHz; (5) Total number of pulses: 10 to 100 pulses are output within a single repair cycle. The hardware implementation process is as follows: Use IGBT power switch devices (such as Infineon FF450R12ME7C_B11) to construct a full-bridge inverter circuit; the turns ratio of the step-up transformer is 1:150 to achieve the rise from the DC bus voltage to the required high voltage level; the control part drives the PWM signal by an FPGA chip (such as Intel Cyclone 10GX); the required energy comes from the supercapacitor bank (rated voltage 750V) in the energy recovery module.

[0142] Specifically, the pulse application electrode is a detachable ring structure made of a composite material of conductive rubber and metal foil, which can closely fit the cable outer skin to ensure that high-voltage pulses are evenly applied to the insulation damage area. The electrical performance requirements of the pulse application electrode are: (1) Insulation withstand voltage level: ≥10 kV; (2) Contact resistance: ≤0.1 Ω; (3) Operating temperature range: -40°C to +100°C; (4) Adaptable cable diameter range: 10 mm to 50 mm. The installation method of the pulse application electrode is: fixed to the located insulation damage point through a magnetic attraction or snap structure; a temperature sensor (such as PT100) is embedded inside to monitor the electrode temperature in real time to prevent overheating from damaging the cable. For example: When an insulation damage is found at 1 meter of the cable, use a ring electrode to wrap this position, connect the output terminal of the high-voltage pulse generator, and prepare to apply pulses.

[0143] Specifically, after the high-voltage pulse application is completed, the repair effect evaluation unit re-measures the insulation resistance value of the cable through the distributed insulation detection system to determine whether the current insulation state meets the safe operation standard. The insulation resistance value after repair is denoted as R post ; the preset recovery threshold is R recover ; if R post < R recover , then trigger the secondary repair mechanism; otherwise, consider the repair successful and the control system stops the repair process. Among them, the preset recovery threshold is set to 700 MΩ; the measurement accuracy is ±1%; the evaluation period is immediately executed after each repair. The hardware implementation process is as follows: Use a high-impedance insulation tester (such as Fluke 1587FC) for measurement; the data transmission interface is the CAN FD protocol; the control logic is processed by an ARM Cortex-M7 microcontroller (such as NXP S32K144); if secondary repair is required, the system will adjust the pulse parameters (such as increasing the voltage or the number of pulses) and execute the repair process again. For example: After the first repair, it is measured that R post = 620 MΩ < R recover = 700 MΩ, it is determined that the repair is not complete, and the control system starts the second repair process, increasing the pulse voltage to V pulse = 5.5 kV and increasing the number of pulses to 80.

[0144] Furthermore, the execution steps of the repair effect evaluation unit are:

[0145] Re-test the insulation resistance value after the pulse is applied, and calculate the corresponding resistance recovery rate;

[0146] When the resistance recovery rate is less than the preset recovery rate threshold, the pulse voltage is increased by a preset multiple corresponding to the current voltage value for secondary repair;

[0147] When the resistance recovery rate corresponding to the secondary repair is less than the preset recovery rate threshold, the damaged insulation portion of the charging cable is marked as unrepairable and the management terminal is notified.

[0148] In an embodiment of the present invention, the repair effect evaluation unit is a key subsystem in the active repair module for judging the repair effect of insulation defects and deciding whether to perform secondary repair. After the high-voltage pulse is applied, the unit re-detects the insulation resistance value of the cable and calculates the resistance recovery rate based on the two measurement data before and after, which serves as the basis for judging whether the repair is effective. Its execution steps include: re-detecting the insulation resistance value after the pulse is applied; calculating the current resistance recovery rate and comparing it with the preset threshold; deciding whether to start secondary repair or mark it as unrepairable based on the recovery rate result; if it is determined to be unrepairable, sending an alarm message to the management terminal.

[0149] Specifically, after the high-voltage pulse is applied, the distributed insulation detection system retests the insulation status of the charging cable to obtain the repaired insulation resistance value R post The original insulation resistance value before repair is recorded as R pre (from the initial test); the insulation resistance value after repair is recorded as R post (from secondary detection); all data are uploaded to the evaluation unit processing module through the CAN FD communication interface. The specific hardware implementation conditions are: use a high-precision insulation tester (such as Megger MIT515) with a range of up to 10TΩ; the measurement error is controlled within ±0.5%; the data update frequency is once per second; and a shielded cable is configured to connect to the evaluation unit to reduce electromagnetic interference. The repair recovery rate calculation formula is:

[0150]

[0151] Where, η is the resistance recovery rate (unit: dimensionless); R post is the insulation resistance value after repair; R pre is the initial insulation resistance value; R target is the ideal insulation resistance target value (usually set to 1GΩ). The judgment logic is: if η≥η threshold , the repair is considered effective and the process ends; if η<η threshold , then the secondary repair mechanism is triggered; where ηthreshold is a preset recovery rate threshold, and a typical value is 0.65 (that is, more than 65% of the target value).

[0152] When it is determined that secondary repair is required, the pulse voltage is increased to c times the current voltage value; the increase multiple c is set according to historical repair experience, and the typical value is 1.2 - 1.5; the new pulse voltage expression is: V new = c·V current , where V new is the new high-voltage pulse voltage adjusted according to the current voltage value during secondary repair, which is used to enhance the repair effect and ensure that the insulation damaged part can be physically repaired more effectively. The unit is volt (V) or kilovolt (kV). c is a dimensionless coefficient, indicating the proportion of increasing the current voltage value during secondary repair, usually set to 1.2 - 1.5, and the specific value can be optimized according to historical repair experience and experimental data. By appropriately increasing the pulse voltage, increasing the intensity of partial discharge or thermal effect, and promoting the recovery of insulating materials. V current is the high-voltage pulse voltage value used during the first repair process, which is used as a basic parameter for calculating the new pulse voltage to ensure that the voltage increase strategy has a clear reference benchmark. The unit is volt (V) or kilovolt (kV). Preferably, the maximum output voltage shall not exceed the safety upper limit of the equipment (such as 6 kV) to avoid damage to the cable or repair device; while increasing the voltage, the pulse width can be appropriately extended (but not exceeding 10 μs), and the total number of pulses can be increased (10% - 20%) to further enhance the repair intensity.

[0153] Furthermore, referring to Figure 5 , the control module adopts a dual-redundancy control system, including a main control unit and a standby control unit. When the main control unit fails, the standby control unit automatically takes over the control within a preset time to ensure the normal operation of the charging pile.

[0154] In the embodiment of the present invention, the control module is the core component to ensure the stable operation of the charging pile system. To improve the reliability and fault tolerance of the system, the control module adopts a dual-redundancy control system (Dual Redundant Control System), including: Main Control Unit (PCU): responsible for daily operation control, data acquisition and instruction execution; Backup Control Unit (BCU): automatically takes over the control right when the main control unit fails to ensure the continuous operation of the system. This system has the following key characteristics:

[0155] (1) Real-time monitoring of the operation status of the main control unit;

[0156] (2) The fault detection and switching response time does not exceed the preset time threshold Tswitch ;

[0157] (3) The switching process requires no manual intervention, ensuring that the charging pile can still operate normally in case of a fault.

[0158] Specifically, the main functions of the main control unit include: being responsible for charging process management (starting, stopping, power regulation); receiving status signals from the insulation detection module, energy recovery module, and active repair module; sending control commands to the actuator (such as contactor operation, pulse application, alarm output, etc.); communicating with external devices (such as BMS, management terminal) through the CAN FD bus. Its hardware configuration includes a microcontroller with an ARM Cortex-M7 core (such as NXP S32K144); a storage unit with a Flash capacity of ≥512KB and a RAM capacity of ≥128KB; communication interfaces including dual-channel CAN FD, one RS485, and one Ethernet; and an operating temperature range of -40°C to +85°C.

[0159] Specifically, the main functions of the standby control unit include: continuously monitoring the working status of the main control unit; taking over the control task within a preset time when an abnormality occurs in the main control unit (such as communication interruption, watchdog timeout, program crash); maintaining the operation of the basic control logic (such as maintaining the current power, triggering an alarm, recording fault information). Its hardware configuration includes a microcontroller: the same or a compatible model as the main control unit (such as TI TMS320F280049); configured with an independent power supply and reset circuit; supporting the hot backup mode (i.e., always running and synchronizing key data); and synchronizing the status with the main control unit through a shared memory or SPI interface. The switching condition judgment formula is: set the heartbeat signal period of the main control unit as T heartbeat , if no valid signal is received within two consecutive cycles, it is determined that the main control unit has a fault:

[0160] if t last_heartbeat +2T heartbeat <t current , then trigger failover;

[0161] where T heartbeat is the time interval of the heartbeat signal regularly sent by the main control unit, in seconds (s). It is used to monitor the working status of the main control unit to ensure its normal operation. If no heartbeat signal is received within the preset time, it is considered that the main control unit may have a fault. t last_heartbeatThe time point of the most recent heartbeat signal received from the main control unit for recording, usually expressed in the form of a timestamp, such as "hour:minute:second" or Unix timestamp (seconds). It serves as the reference time point for judging whether the main control unit has a fault. By comparing the current time and the most recent heartbeat time, it can be determined whether the main control unit has sent a heartbeat signal within the specified time. t current Is the current time point of the system, also expressed in the form of a timestamp. It is used for real-time monitoring and calculating the difference from the most recent heartbeat time to judge whether the switching condition is met. For example: If it is set that T heartbeat = 1s, and the most recent heartbeat time is t = 10:00:00, and the current time is t = 10:00:03, the switching condition is met, and the system immediately enables the standby control unit.

[0162] The time interval from detecting the failure of the main control unit to the standby control unit completing the takeover is denoted as T failover , and it is required to be less than the preset time threshold T switch . The switching time formula used is: T failover = T detect + T switching .

[0163] Among them, T failover is the time interval from detecting the failure of the main control unit to the standby control unit completing the takeover; T detect is the time required for fault detection; T switching is the time required for the transfer of control rights. The preset time threshold T switch = 2s, which meets the requirement of fast switching. The specific hardware implementation process is to use a watchdog timer to monitor the operating status of the main control unit; configure a dual-channel relay as the control signal switching switch; the standby control unit is built-in with the minimum operating mode firmware and can independently maintain the basic control logic.

[0164] The system recovery strategy is: If the main control unit returns to normal after a period of time (such as a successful restart), the system will re-evaluate its status; if it is confirmed to be correct, the standby control unit can hand over the control right to the main control unit; the switching process needs to ensure data consistency and prevent control conflicts.

[0165] The fault alarm mechanism is: After triggering the switch, an LED indicator and a buzzer are used to prompt the failure of the main control unit; at the same time, a fault message is sent to the management terminal through the wireless communication module. For example: After the system switches, the management terminal receives the above alarm message in JSON format, and the operation and maintenance personnel can judge whether on-site maintenance is required according to the information.

[0166] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An energy recovery type intelligent charging pile, characterized in that, Comprising: A charging pile body and a charging module, a control module, an insulation monitoring module, a fault warning module, an energy recovery module and an active repair module provided on the charging pile body; the charging module is connected to a device to be charged through a charging cable; The insulation monitoring module is configured to monitor the insulation resistance value of the charging cable in real time, compare it with a preset multi-level threshold, and generate comparison data; The fault warning module is configured to trigger a multi-level processing mechanism including warning, power-down charging, and open circuit according to the comparison data; The energy recovery module is configured to store the remaining electric energy in the charging circuit when the fault trigger data includes triggering power-down or open circuit; The active repair module is configured to generate a high-voltage pulse with a preset peak frequency using the electric energy stored by the energy recovery module, and physically repair the insulation damaged part of the charging cable.

2. The energy recovery type intelligent charging pile according to claim 1, characterized in that, The insulation monitoring module includes a distributed insulation detection unit, a dynamic threshold adjustment unit, and a comparison unit; The distributed insulation detection unit includes a plurality of insulation detection sensors, which are arranged at intervals on the outer insulation layer surface of the charging cable in a spiral winding manner, and are used to synchronously detect the temperature, humidity, and insulation resistance value of each position along the axial direction of the charging cable, and generate temperature data, humidity data, and insulation resistance value; The dynamic threshold adjustment unit is configured to dynamically correct the threshold using the temperature data, the humidity data, and a historical insulation degradation curve through an adaptive algorithm to generate a target multi-level threshold; The comparison unit is configured to compare the insulation resistance value with the target multi-level threshold to generate comparison data.

3. The energy recovery type intelligent charging pile according to claim 2, wherein The distributed insulation detection unit further includes: A sensor self-calibration module, which is configured to substitute the temperature data, the humidity data, and the insulation resistance value into a preset resistance compensation formula, calculate an insulation resistance correction value, and send it to the comparison unit; A high-frequency pulse injection module, which is configured to inject a non-destructive high-voltage pulse signal into the charging cable, calculate the internal partial discharge amount of the cable by detecting the pulse attenuation characteristic, and send the partial discharge amount as an auxiliary parameter to the dynamic threshold adjustment unit.

4. The energy recovery type intelligent charging pile according to claim 2, wherein The execution steps of the dynamic threshold adjustment unit are: Filter and denoise the temperature data and the humidity data to generate target temperature data and target humidity data; Calculate an environmental parameter comprehensive influence factor using the target temperature data, the target humidity data, and a preset upper limit value of temperature and humidity; Predict the baseline threshold at the current moment using the historical insulation degradation curve; Correct the baseline threshold using the environmental parameter comprehensive influence factor to generate a target multi-level threshold.

5. The energy recovery type intelligent charging pile according to claim 4, characterized in that, The target multi-level threshold includes a normal threshold, a warning threshold, and a fault threshold; the execution steps of the fault warning module are: When the comparison data is that the insulation resistance value is lower than the normal threshold and higher than the warning threshold, trigger a warning mechanism and send a warning signal through an acoustic and optical alarm device; When the comparison data is that the insulation resistance value is lower than the warning threshold and higher than the fault threshold, trigger a power-down charging mechanism, and linearly reduce the charging power to a preset range of the rated power according to the deviation ratio of the insulation resistance value from the warning threshold; When the comparison data is that the insulation resistance value is lower than the fault threshold, trigger the open - circuit mechanism, cut off the charging circuit, and send a fault message to the management terminal through the wireless communication module.

6. The energy recovery type intelligent charging pile according to claim 5, characterized in that, The energy recovery module includes a bidirectional DC converter, a supercapacitor bank, and a charge - discharge control unit; The bidirectional DC converter is connected to the charging circuit and the supercapacitor bank, and is used to switch to the electric energy recovery mode when the power is reduced or the circuit is opened; The supercapacitor bank is used to store the remaining electric energy in the charging circuit; The charge - discharge control unit is used to trigger overload protection and stop recovery when the remaining electric energy is greater than or equal to the preset rated capacity.

7. The energy recovery type intelligent charging pile according to claim 1, characterized in that The execution steps of the active repair module are as follows: Based on the broken - position location algorithm of the traveling - wave ranging principle, calculate the insulation break position through the pulse reflection time difference; Generate a high - voltage pulse with a preset peak frequency using the electric energy stored in the energy recovery module, and physically repair the insulation break part of the charging cable; During the repair process, real - time monitor the pulse attenuation rate. When the pulse attenuation rate drops by greater than or equal to the preset drop threshold, it is determined that the repair is completed.

8. The energy recovery type intelligent charging pile according to claim 1, wherein, The active repair module includes a high - voltage pulse generator, a repair effect evaluation unit, and a pulse application electrode. The pulse application electrode wraps the insulation break part of the charging cable in an annular structure; The high - voltage pulse generator is used to output a square pulse and transmit it to the pulse application electrode; The repair effect evaluation unit is used to re - detect the insulation resistance value after the pulse is applied. If the new insulation resistance value is less than the preset recovery threshold, trigger secondary repair.

9. The energy recovery type intelligent charging pile according to claim 8, wherein, The execution steps of the repair effect evaluation unit are as follows: Re - detect the insulation resistance value after the pulse is applied, and calculate the corresponding resistance recovery rate; When the resistance recovery rate is less than the preset recovery rate threshold, increase the pulse voltage by a preset multiple corresponding to the current voltage value for secondary repair; When the resistance recovery rate corresponding to the secondary repair is less than the preset recovery rate threshold, mark the insulation break part of the charging cable as irreparable and notify the management terminal.

10. The energy recovery type intelligent charging pile according to claim 1, wherein The control module adopts a dual - redundant control system, including a main control unit and a standby control unit. When the main control unit fails, the standby control unit automatically takes over the control within a preset time to ensure the normal operation of the charging pile.

Images