High-voltage single-core cable intermediate joint grounding system

Abstract

The invention relates to the technical field of data processing, in particular to a high-voltage single-core cable intermediate joint grounding system which comprises an intermediate joint module, a grounding cable module, a grounding box module and a control device module. The intermediate joint module adopts a stepped silver-plated contact surface to embed a contact resistance monitoring unit; the control device module collects a resistance signal, a discharge current signal, a temperature rise signal and a surge frequency signal through a communication bus, calls pre-stored historical data and a fault mode library containing a fault mapping relation, and inputs the data into the genetic algorithm unit to generate a crimping adjustment instruction, a surge sensitivity instruction or a maintenance early warning instruction. And the system executes a crimping adjustment instruction to dynamically adjust the oil pressure of the hydraulic execution mechanism, executes a surge sensitivity instruction to modify the conduction threshold value of the surge protection unit, and executes a maintenance early warning instruction to push a grading maintenance notification. Through cooperation of structure optimization and closed-loop control, contact resistance rise, circulation accumulation and overvoltage impact are inhibited, and risks of grounding failure and cable sheath breakdown are reduced.

Description

Technical Field

[0001] This invention relates to the field of technology, and more particularly to a grounding system for a high-voltage single-core cable intermediate joint. Background Technology

[0002] When high-voltage single-core cables operate in high-voltage power transmission, the metal sheath or shielding layer will generate a significant induced voltage due to the electromagnetic induction effect of the conductor current. If left uncontrolled, this can lead to voltage imbalance, excessive potential difference, and increased risk of electric shock and partial discharge. Therefore, grounding systems are indispensable in cable networks. In particular, the grounding design of intermediate joints must consider eliminating overheating losses caused by induced circulating currents between metal sheaths. By adopting cross-interconnected grounding or direct grounding methods, a balanced potential distribution can be achieved, thereby optimizing electromagnetic compatibility, reducing interference to surrounding equipment, and dispersing fault currents to maintain stable system operation and extend equipment life.

[0003] The existing high-voltage single-core cable intermediate joint grounding system suffers from increased contact resistance due to unoptimized contact surfaces between the intermediate joint and the grounding cable (such as rough surfaces and easy wear of the tin plating layer). Combined with the poor current discharge capacity caused by the use of hard copper stranded wire in the grounding cable (large bending radius and insufficient conductivity), this leads to localized heating, insulation aging, and the accumulation of circulating current, ultimately resulting in frequent grounding failures and cable sheath breakdown. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a grounding system for intermediate joints of high-voltage single-core cables, which solves the problems of frequent grounding failures and cable sheath breakdown.

[0005] To solve the above-mentioned technical problems, the specific technical solution of the present invention is as follows:

[0006] This invention provides a high-voltage single-core cable intermediate joint grounding system, comprising:

[0007] The intermediate connector module has a stepped metal sheath contact surface that is silver-plated, and the stepped structure is embedded with a contact resistance monitoring unit.

[0008] The grounding cable module is made of multi-strand soft copper stranded wire. The outer sheath of the grounding cable module has a monitoring hole and a built-in current sensing unit.

[0009] The grounding box module is equipped with a temperature sensing unit and a surge protection unit, and the surge protection unit is configured with an action counting unit.

[0010] The control device module is connected to the contact resistance monitoring unit, current sensing unit, temperature sensing unit and action counting unit via a communication bus;

[0011] The control device module is configured as follows:

[0012] The resistance signal of the contact resistance monitoring unit, the discharge current signal of the current sensing unit, the temperature rise signal of the temperature sensing unit, and the surge frequency signal of the action counting unit are collected.

[0013] Retrieve its internally stored pre-stored historical data and fault mode library, wherein the fault mode library includes the mapping relationship between resistance threshold, temperature rise threshold and fault type;

[0014] The acquired signal, the historical data, and the fault mode library are input into the genetic algorithm unit, and the genetic algorithm unit outputs a crimping adjustment command, a surge sensitivity command, or a maintenance warning command.

[0015] The control device module executes the crimping adjustment command to adjust the hydraulic actuator oil pressure, executes the surge sensitivity command to modify the surge protection unit's conduction voltage threshold, and executes the maintenance early warning command to push maintenance notifications.

[0016] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention also includes: the contact resistance monitoring unit adopting the four-terminal detection principle, which contacts the metal sheath step surface through a probe array set on the step surface of the stepped structure.

[0017] The contact resistance monitoring unit acquires the resistance value based on probe contact data;

[0018] The communication bus is an RS485 bus that transmits the Modbus RTU protocol to realize data transmission between each monitoring unit and the control device module in claim 1.

[0019] Furthermore, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the control device module includes a microprocessor and a storage unit;

[0020] The storage unit continuously records and generates historical change curves of resistance signal, discharge current signal, temperature rise signal, and surge frequency signal during system operation, forming pre-stored historical data;

[0021] The microprocessor executes the genetic algorithm unit.

[0022] Furthermore, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the genetic algorithm unit is configured as follows:

[0023] The pressure adjustment command, surge sensitivity command, and maintenance warning command are encoded into genetic sequences, generating multiple sets of genetic sequences to form an initial population. The fitness value of each set of genetic sequences is calculated based on the collected signals and pre-stored historical data. The fitness value is a weighted calculation result of resistance difference, discharge current deviation, and temperature rise and fall. The top 20% of individuals with the highest fitness values ​​are selected to enter the next generation population. Gene crossover and gene mutation operations are performed on the next generation population. When the number of iterations reaches 50 or the change in fitness value is less than 5%, the optimal genetic sequence is output as the control command.

[0024] Furthermore, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the gene crossover operation includes: selecting a single crossover position in the genetic sequence and exchanging the gene segment corresponding to the crimping force parameter and the gene segment corresponding to the surge sensitivity parameter;

[0025] The gene mutation operation includes: randomly selecting 10% of gene segments and applying a ±0.2MPa perturbation to the crimping force parameter or a ±0.05 times rated voltage perturbation to the conduction threshold corresponding to the surge sensitivity parameter.

[0026] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes:

[0027] When the resistance signal exceeds the resistance threshold in the fault mode library, the genetic algorithm unit is configured as follows:

[0028] The dynamic pressure compensation coefficient is generated by integrating the temperature rise signal and the discharge current signal. Based on the dynamic pressure compensation coefficient, the hydraulic compensation parameters are calculated, and the pressure adjustment command is output to the hydraulic actuator.

[0029] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: when the temperature rise signal reaches the temperature rise threshold of the fault mode library and the surge frequency signal exceeds 5 times within 10 minutes, the genetic algorithm unit outputs a surge sensitivity command, and the surge sensitivity command modifies the conduction voltage threshold of the MOV element in the surge protection unit, so that the conduction voltage threshold is reduced by 15% of the original threshold.

[0030] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention also includes: when the discharge current signal is lower than 60% of the rated value for 24 consecutive hours, the genetic algorithm unit retrieves the soft copper stranded wire aging curve recorded in the storage unit, generates a warning level parameter based on the degree of deviation between the aging curve and the discharge current signal, and outputs a multi-level maintenance warning command corresponding to the level.

[0031] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: the grounding box module adopts a sealed and moisture-proof structure with an IP65 protection level, and the inner wall of the grounding box is provided with a copper-nickel alloy electromagnetic shielding layer with a thickness of 0.5mm;

[0032] The surge protection unit includes a discharge channel assembly composed of an MOV varistor array;

[0033] The action counting unit records the number of conduction events of the MOV varistor array in real time and serves as the source of surge frequency signals.

[0034] Furthermore, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes:

[0035] The fault mode library is stored using predefined mapping rules:

[0036] The contact resistance threshold range corresponds to the contact surface oxidation fault type, the temperature rise threshold range corresponds to the current overload fault type, and the surge frequency threshold range corresponds to the voltage surge fault type.

[0037] The genetic algorithm unit is configured to extract the threshold interval deviation in the mapping relationship between real-time acquired signals and fault types, generate fitness weight adjustment coefficients based on the deviation, and recalculate the fitness value using the weight adjustment coefficients.

[0038] Beneficial effects of this invention;

[0039] The beneficial effects of this invention are reflected in three aspects of technological synergy: the stepped silver-plated contact surface structure reduces the initial contact resistance, and the multi-strand soft copper stranded wire enhances the current discharge capacity, thus physically blocking the source of local overheating; the multi-source signal fusion mechanism, through real-time interactive verification of contact resistance, discharge current, temperature rise, and surge frequency, builds the early identification capability of contact surface oxidation, current overload, and voltage surge faults; the closed-loop control driven by the genetic algorithm dynamically generates crimp adjustment, surge sensitivity adjustment, and graded maintenance instructions based on the fault mode library mapping relationship, realizing adaptive optimization of contact pressure, accelerated overvoltage response, and accurate early warning of cable aging, effectively suppressing the accumulation of circulating current in the metal sheath, maintaining the integrity of the sheath insulation, and significantly reducing the risk of grounding failure and sheath breakdown. Attached Figure Description

[0040] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0041] Figure 1 This is a system architecture diagram of a high-voltage single-core cable intermediate joint grounding system provided for an embodiment of the present invention. Figure 2 This is a schematic diagram of the overall connection of a grounding system for a high-voltage single-core cable intermediate joint grounding system provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. The technical solutions provided by various embodiments of this invention will be described in detail below with reference to the accompanying drawings. To better understand the objectives of this invention, it will be described in further detail below.

[0043] Please see Figure 1 The present invention provides a grounding system for a high-voltage single-core cable intermediate joint, comprising:

[0044] The intermediate connector module has a stepped metal sheath contact surface that is silver-plated, and the stepped structure is embedded with a contact resistance monitoring unit.

[0045] The grounding cable module is made of multi-strand soft copper stranded wire. The outer sheath of the grounding cable module has a monitoring hole and a built-in current sensing unit.

[0046] The grounding box module is equipped with a temperature sensing unit and a surge protection unit, and the surge protection unit is configured with an action counting unit.

[0047] The control device module is connected to the contact resistance monitoring unit, current sensing unit, temperature sensing unit and action counting unit via a communication bus;

[0048] The control device module is configured as follows:

[0049] The resistance signal of the contact resistance monitoring unit, the discharge current signal of the current sensing unit, the temperature rise signal of the temperature sensing unit, and the surge frequency signal of the action counting unit are collected.

[0050] Retrieve its internally stored pre-stored historical data and fault mode library, wherein the fault mode library includes the mapping relationship between resistance threshold, temperature rise threshold and fault type;

[0051] The acquired signal, the historical data, and the fault mode library are input into the genetic algorithm unit, and the genetic algorithm unit outputs a crimping adjustment command, a surge sensitivity command, or a maintenance warning command.

[0052] The control device module executes the crimping adjustment command to adjust the hydraulic actuator oil pressure, executes the surge sensitivity command to modify the surge protection unit's conduction voltage threshold, and executes the maintenance early warning command to push maintenance notifications.

[0053] The high-voltage single-core cable intermediate joint grounding system includes an intermediate joint module, a grounding cable module, a grounding box module, and a control device module. The intermediate joint module uses a stepped metal sheath contact surface, which is silver-plated to reduce contact resistance and oxidation risk. A contact resistance monitoring unit embedded in the stepped structure detects real-time resistance changes between the metal sheaths and generates a resistance signal. The grounding cable module is composed of multiple strands of soft copper wire, and its outer sheath has a monitoring hole with a built-in current sensing unit that continuously collects the cable sheath discharge current signal and monitors abnormal current fluctuations.

[0054] The grounding box module integrates a temperature sensing unit and a surge protection unit. The temperature sensing unit monitors temperature rise changes within the grounding box and generates a temperature rise signal. The surge protection unit, equipped with an action counting unit, records the number of overvoltage events and outputs a surge frequency signal. The control device module connects to each monitoring unit via an industrial communication bus, establishing a multi-source data interaction channel.

[0055] The control unit module executes a hierarchical control process. The signal acquisition layer synchronously acquires resistance signals, discharge current signals, temperature rise signals, and surge frequency signals to form a real-time system status dataset. The data fusion layer calls the pre-stored historical data and fault mode library stored internally by the module. The fault mode library has three sets of mapping rules: resistance threshold range with contact surface oxidation fault type, temperature rise threshold range with current overload fault type, and surge frequency threshold range with voltage impulse fault type, to achieve matching analysis between real-time data and fault characteristics.

[0056] The intelligent decision-making layer inputs collected signals, pre-stored historical data, and fault mapping relationships into the genetic algorithm unit. This unit encodes the requirements for crimping adjustment, surge sensitivity adjustment, and maintenance early warning into genetic sequences, and generates three types of instructions through population iterative optimization: crimping adjustment instructions correspond to pressure adjustment of the hydraulic actuator, surge sensitivity instructions modify the conduction voltage threshold of the surge protection unit, and maintenance early warning instructions trigger preset maintenance procedures. The execution feedback layer drives the hydraulic actuator to change the contact surface crimping force, optimizes the overvoltage response characteristics of the surge protection unit, and pushes the maintenance requirements to the monitoring terminal.

[0057] The contact resistance monitoring data of the intermediate joint module and the discharge current signal of the grounding cable module in this invention jointly reflect the sheath circulation current status; the temperature rise signal of the grounding box module and the surge frequency signal jointly indicate overload and impact risk; the control device module associates physical signals with fault types through fault mode library mapping rules, and the genetic algorithm unit dynamically adjusts and optimizes the target weights according to the mapping relationship, ultimately generating execution instructions that match the fault type. This invention achieves the technical effects of suppressing circulating current in the metal sheath of the grounding system, optimizing the joint contact status, and providing rapid response to surge faults.

[0058] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: the contact resistance monitoring unit adopting the four-terminal detection principle, which contacts the metal sheath step surface through a probe array set on the step surface of the stepped structure.

[0059] The contact resistance monitoring unit acquires the resistance value based on probe contact data;

[0060] The communication bus is an RS485 bus that transmits the Modbus RTU protocol to realize data transmission between each monitoring unit and the control device module in claim 1.

[0061] The contact resistance monitoring unit employs a four-terminal detection principle for resistance measurement. A probe array, comprising independent current-excitation probes and voltage acquisition probes, is positioned on the stepped surface of the stepped structure. The current-excitation probes inject a constant current into the stepped surface of the metal sheath, while the voltage acquisition probes simultaneously detect changes in the potential difference between the metal sheaths. Contact impedance errors are eliminated by calculating the voltage-to-current ratio, thus improving the accuracy of resistance measurement. This design is suitable for high-voltage cable joints operating in environments with contact oxidation or surface contamination.

[0062] The contact resistance monitoring unit uses raw current and voltage data collected by the probe array to perform Ohm's law calculations to obtain the resistance value. The calculation process filters out signal fluctuations caused by environmental electromagnetic interference, generating a continuous resistance change curve. This resistance value serves as a core characterization parameter of the intermediate joint's contact status, used to identify abnormal resistance increases caused by oxidation or loosening of the contact surface.

[0063] The communication bus uses the RS485 physical layer standard to construct a differential signal transmission channel, combined with the Modbus RTU protocol to define the data transmission protocol. The RS485 bus uses a twisted-pair structure to suppress common-mode interference, adapting to the strong electromagnetic environment of high-voltage cable grounding systems. The Modbus RTU protocol specifies the address allocation mechanism, data frame verification rules, and master-slave communication timing for each monitoring unit, enabling multi-node data interaction between the contact resistance monitoring unit, current sensing unit, temperature sensing unit, action counting unit, and control device module. This bus architecture meets the real-time transmission requirements of monitoring data and supports the implementation of the system's closed-loop control function.

[0064] Specifically, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the control device module includes a microprocessor and a storage unit;

[0065] The storage unit continuously records and generates historical change curves of resistance signal, discharge current signal, temperature rise signal, and surge frequency signal during system operation, forming pre-stored historical data;

[0066] The microprocessor executes the genetic algorithm unit.

[0067] The control unit module comprises two core components: a microprocessor and a storage unit. The storage unit continuously records the raw data of resistance signals, discharge current signals, temperature rise signals, and surge frequency signals at a fixed sampling period, generating a data stream with time-series characteristics based on timestamps. This data stream is divided into discrete data segments using a sliding time window. Each data segment undergoes smoothing filtering to eliminate impulse noise interference, constructing a historical change curve reflecting the signal's trend.

[0068] The storage unit employs a circular buffer storage mechanism to dynamically update historical data. The oldest data segment is automatically replaced as new data is continuously written, always retaining data from the most recent complete operating cycle. Historical change curves include signal amplitude, rate of change, and fluctuation frequency characteristics, forming a pre-stored historical dataset describing the system's operating state. This dataset serves as a benchmark reference template for the system's normal operating state.

[0069] The microprocessor executes the genetic algorithm unit, reading pre-stored historical data from the storage unit as baseline parameters for algorithm iteration. The pre-stored historical data and real-time acquired signals form a longitudinal comparison relationship. The genetic algorithm unit identifies abnormal operating states by comparing the feature offsets of the real-time signals and historical curves. The data update mechanism of the storage unit and the algorithm calls of the microprocessor form a closed loop: newly generated real-time signals are processed and added to the historical curves, continuously optimizing the accuracy of the pre-stored historical data representation.

[0070] Specifically, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the genetic algorithm unit is configured as follows:

[0071] The pressure adjustment command, surge sensitivity command, and maintenance warning command are encoded into genetic sequences, generating multiple sets of genetic sequences to form an initial population. The fitness value of each set of genetic sequences is calculated based on the collected signals and pre-stored historical data. The fitness value is a weighted calculation result of resistance difference, discharge current deviation, and temperature rise and fall. The top 20% of individuals with the highest fitness values ​​are selected to enter the next generation population. Gene crossover and gene mutation operations are performed on the next generation population. When the number of iterations reaches 50 or the change in fitness value is less than 5%, the optimal genetic sequence is output as the control command.

[0072] The genetic algorithm unit encodes three types of control variables—crimping adjustment commands, surge sensitivity commands, and maintenance warning commands—into digitized genetic sequences. Each sequence represents a complete combination of control parameters. The encoding process divides the data into independent gene segments based on command type: the crimping adjustment command corresponds to the hydraulic pressure value gene segment, the surge sensitivity command corresponds to the conduction voltage threshold gene segment, and the maintenance warning command corresponds to the warning level gene segment. The initial population is constructed by randomly generating multiple sets of gene sequences, covering the possible control parameter space.

[0073] Fitness calculation is based on feature comparison between real-time acquired signals and pre-stored historical data. For each set of gene sequences and corresponding control parameter combinations, the system simulates the control effect under that combination, calculating three core indicators: the difference between the resistance signal and the historical benchmark, the deviation of the discharge current signal from the standard waveform, and the rate of decrease in the temperature rise signal. The fitness value is formed by weighted fusion of the results of multiple indicators, which reflects the degree of optimization of the system state by the control parameter combination.

[0074] During the selection phase, a predetermined proportion of individuals with the highest fitness values ​​are retained for the next generation. The selection mechanism employs a roulette wheel selection strategy, where individuals with high fitness have a higher probability of inheritance, maintaining population diversity while guiding the direction of optimization. The next generation is updated through gene crossover and gene mutation operations: crossover swaps corresponding gene segments of two parent gene sequences at randomly selected single locations, and mutation randomly modifies the parameter values ​​of individual gene positions.

[0075] The iteration termination condition is determined based on the optimization convergence state. When the genetic iteration reaches a preset number of iterations or the change in the highest fitness value of the population falls below a set threshold, the algorithm terminates and outputs the current optimal gene sequence. This sequence is decoded and restored into specific compression adjustment commands, surge sensitivity commands, and maintenance warning commands, which are then issued and executed as the final control commands. The entire optimization process achieves adaptive matching between control parameters and system dynamic characteristics.

[0076] Specifically, in the high-voltage single-core cable intermediate joint grounding system of the present invention, the gene crossover operation includes: selecting a single crossover position in the genetic sequence and exchanging the gene segment corresponding to the crimping force parameter and the gene segment corresponding to the surge sensitivity parameter.

[0077] The gene mutation operation includes: randomly selecting 10% of gene segments and applying a ±0.2MPa perturbation to the crimping force parameter or a ±0.05 times rated voltage perturbation to the conduction threshold corresponding to the surge sensitivity parameter.

[0078] The genetic algorithm unit performs parameter combination optimization through gene crossover. During the selection of a single crossover location, the system traverses the encoding interval of the genetic sequence to determine the boundary separation point between the gene segment corresponding to the crimping force parameter and the gene segment corresponding to the surge sensitivity parameter. The exchange operation swaps and recombines the corresponding gene segments of two parent individuals to generate a new gene sequence that integrates different control strategies. This operation simulates the collaborative optimization mechanism of hydraulic pressure regulation and surge protection threshold adjustment, and is suitable for coupled scenarios of high-voltage cable joint contact pressure and overvoltage protection.

[0079] Gene mutation operations introduce controllable random perturbations. The random selection mechanism locates the gene segment to be mutated based on a uniform distribution principle. A directional offset perturbation is applied to the crimping force parameter to form a pressure compensation fine-tuning scheme; a proportional offset perturbation is applied to the surge sensitivity parameter to achieve adaptive correction of the conduction threshold. The perturbation amplitude design considers the resolution of the hydraulic actuator and the electrical characteristics of the surge protection components, ensuring the mutation results are engineering-feasible.

[0080] Crossover and mutation operations form a closed-loop technical logic. Crossover operations explore the parameter combination space of crimping force and surge sensitivity, solving the problem of synergistic optimization between contact surface pressure balance and overvoltage response; mutation operations break through the limitations of local optima, enhancing the algorithm's adaptability to sudden operating conditions in grounding systems. Both operations jointly maintain population diversity, ensuring optimization directionality while avoiding premature convergence, providing an evolutionary basis for the generation of control commands under complex operating environments.

[0081] The operation process is deeply coupled with the system hardware. The parameter combinations generated by cross-polling drive the hydraulic actuator through a digital-to-analog converter, realizing dynamic adjustment of the metal sheath contact pressure; the threshold correction instructions generated by mutation are directly written into the surge protection unit register, changing the conduction characteristics of the metal oxide varistor. This design makes the genetic operation physically executable, completing the entire technology chain from digital optimization to equipment control.

[0082] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes:

[0083] When the resistance signal exceeds the resistance threshold in the fault mode library, the genetic algorithm unit is configured as follows:

[0084] The dynamic pressure compensation coefficient is generated by integrating the temperature rise signal and the discharge current signal. Based on the dynamic pressure compensation coefficient, the hydraulic compensation parameters are calculated, and the pressure adjustment command is output to the hydraulic actuator.

[0085] When the resistance signal exceeds the preset resistance threshold range in the fault mode library, the genetic algorithm unit initiates the contact surface abnormal response process. This process integrates the temperature rise signal and the discharge current signal for joint analysis: the temperature rise signal characterizes the degree of heating at the contact point, and the discharge current signal reflects the conductivity state of the grounding channel. The two signals are weighted by an algorithm to generate a dynamic pressure compensation coefficient. This coefficient quantifies the intensity of the contact surface pressure compensation requirement, and the coefficient value increases positively correlated with the temperature rise rate and the current deviation.

[0086] When calculating hydraulic compensation parameters based on dynamic pressure compensation coefficients, the system uses a linear mapping model to convert the coefficient values ​​into pressure regulation values ​​of the hydraulic actuator. These pressure regulation values ​​are then superimposed onto the baseline pressure contact force value to form hydraulic compensation parameters adapted to real-time operating conditions. The calculation process incorporates the rate of change of discharge current as a correction factor; when the current drops sharply, the compensation amplitude is increased to suppress the risk of instantaneous deterioration of the contact surface.

[0087] During the process of outputting the crimping adjustment command to the hydraulic actuator, the command code includes three elements: target pressure value, adjustment rate, and duration. The hydraulic actuator drives the piston displacement according to the command parameters, changing the crimping force of the intermediate joint's metal sheath. Increasing the pressure improves the micro-contact point distribution on the stepped contact surface, reducing transition resistance; decreasing the pressure avoids excessive deformation that could damage the silver plating layer. This mechanism achieves adaptive adjustment under abnormal contact resistance conditions, solving the problem of uncontrollable resistance increases caused by contact surface oxidation in traditional grounding systems.

[0088] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: when the temperature rise signal reaches the temperature rise threshold of the fault mode library and the surge frequency signal exceeds 5 times within 10 minutes, the genetic algorithm unit outputs a surge sensitivity command, and the surge sensitivity command modifies the conduction voltage threshold of the MOV element in the surge protection unit, so that the conduction voltage threshold is reduced by 15% of the original threshold.

[0089] When the temperature rise signal continuously exceeds the temperature rise threshold range set in the fault mode library, and the surge frequency signal exceeds the standard frequency within the set time window, the genetic algorithm unit determines that the system is in an overload and voltage surge coupled state. This composite fault mode triggers the surge sensitivity command generation process, and the command target is the metal oxide varistor component in the surge protection unit.

[0090] The surge sensitivity command includes a conduction voltage threshold adjustment parameter, which reconfigures the electrical characteristics of the metal oxide varistor through a proportional correction mode. Specifically, the control module writes the new threshold parameter to the surge protection unit's register, driving the metal oxide varistor array to update the operating voltage reference. Lowering the threshold enhances overvoltage response sensitivity and accelerates surge energy dissipation.

[0091] This operation mitigates the cumulative risk of voltage surges under overload conditions. Excessive temperature rise indicates a current overload in the grounding system; increased surge frequency at this point exacerbates insulation degradation. Lowering the on-state voltage threshold can prematurely dissipate surge energy, breaking the positive feedback loop between temperature rise and voltage surge. The characteristics of the metal oxide varistor are adjusted via a digital potentiometer or programmable logic, ensuring real-time and reliable parameter modification.

[0092] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: when the discharge current signal is lower than 60% of the rated value for 24 consecutive hours, the genetic algorithm unit retrieves the soft copper stranded wire aging curve recorded in the storage unit, generates a warning level parameter based on the degree of deviation between the aging curve and the discharge current signal, and outputs a multi-level maintenance warning command corresponding to the level.

[0093] When the discharge current signal remains below the set percentage of the rated discharge current for a set duration, the genetic algorithm unit activates the aging assessment process. This process retrieves the historical aging curves of the soft copper stranded wire recorded in the storage unit. The aging curves include current decay characteristic data under different operating cycles, reflecting the gradual change in the conductivity of the grounding cable.

[0094] The deviation between the aging curve and the real-time discharge current signal is calculated using a dynamic time warping algorithm. This algorithm aligns the waveform feature points of the historical curve and the real-time signal, calculates the current amplitude attenuation rate and fluctuation mode differences, and generates quantified deviation parameters. These deviation parameters are mapped to warning level parameters via a piecewise linear function, and the level classification is determined based on the remaining life prediction model of the grounding cable.

[0095] When outputting multi-level maintenance early warning commands, the early warning level parameters drive the hierarchical generation of command content. A low-level early warning triggers a flashing alarm on the grounding box status indicator light; a medium-level early warning activates a local buzzer and sends an SMS notification; and a high-level early warning directly links to the power grid dispatch system to generate a maintenance work order. This hierarchical mechanism optimizes the allocation of maintenance resources, avoiding over-maintenance or insufficient response.

[0096] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes: the grounding box module adopts a sealed and moisture-proof structure with an IP65 protection level, and the inner wall of the grounding box is provided with a copper-nickel alloy electromagnetic shielding layer with a thickness of 0.5mm;

[0097] The surge protection unit includes a discharge channel assembly composed of an MOV varistor array;

[0098] The action counting unit records the number of conduction events of the MOV varistor array in real time and serves as the source of surge frequency signals.

[0099] The grounding box module adopts a sealed and moisture-proof structure that meets the IP65 protection standard. The joint surfaces of the box are equipped with silicone rubber sealing rings and moisture-proof breather valves. This structure blocks the path of external moisture infiltration and is suitable for the high humidity environment of high-voltage cable wells. The inner wall of the box is covered with a copper-nickel alloy electromagnetic shielding layer, which attenuates power frequency magnetic field interference through the eddy current effect and reduces the risk of signal distortion of the temperature sensing unit.

[0100] The surge protection unit consists of multiple sets of metal oxide varistors connected in parallel to form a discharge channel assembly. Each varistor unit is connected in a star topology, and the discharge channel assembly is equipped with a thermal trip mechanism. When the overvoltage surge energy exceeds the assembly's capacity, the thermal trip mechanism disconnects the faulty unit while maintaining normal operation of other branches, thus improving the fault tolerance of the discharge system.

[0101] The action counting unit detects the conduction current of the discharge channel assembly based on a Hall current sensor. When the metal oxide varistor array conducts discharge, the sensor outputs a pulse signal to trigger the counting operation. The counting result is converted into a surge frequency signal by an event encoder, which includes conduction timestamp, peak current, and accumulated energy characteristic data. This signal serves as the direct source of the surge frequency signal input to the control device module.

[0102] Specifically, the high-voltage single-core cable intermediate joint grounding system of the present invention further includes:

[0103] The fault mode library is stored using predefined mapping rules:

[0104] The contact resistance threshold range corresponds to the contact surface oxidation fault type, the temperature rise threshold range corresponds to the current overload fault type, and the surge frequency threshold range corresponds to the voltage surge fault type.

[0105] The genetic algorithm unit is configured to extract the threshold interval deviation in the mapping relationship between real-time acquired signals and fault types, generate fitness weight adjustment coefficients based on the deviation, and recalculate the fitness value using the weight adjustment coefficients.

[0106] The fault mode library establishes a fault type identification benchmark through predefined mapping rules. The library stores three core mapping relationships: the contact resistance threshold range is associated with contact surface oxidation faults, and when the resistance value falls into a specific range, it is determined that the silver plating layer is deteriorated or the contact pressure is insufficient; the temperature rise threshold range is associated with current overload faults, and an excessive rate of temperature change indicates that there is circulating current accumulation in the grounding cable; the surge frequency threshold range is associated with voltage impulse faults, and an abnormally high frequency reflects that the insulation is damaged by transient overvoltage.

[0107] When the genetic algorithm unit extracts the threshold interval deviation of the mapping relationship between real-time acquired signals and fault types, it performs signal feature decoupling operations. For resistance signals, it calculates the Euclidean distance between the signal and the contact resistance threshold interval to generate a contact state offset; for temperature rise signals, it analyzes the duration of the signal crossing the temperature rise threshold interval to generate an overload risk accumulation; and for surge frequency signals, it statistically analyzes the probability distribution within the frequency threshold interval to generate an impact intensity deviation. These three types of deviations constitute a multi-dimensional feature vector.

[0108] The process of generating fitness weight adjustment coefficients based on deviations employs a fuzzy decision-making mechanism. When the contact state offset increases, the weight coefficient of the crimping adjustment command is increased; when the accumulated overload risk increases, the weight ratio of the maintenance warning command is strengthened; and when the impact intensity deviation expands, the weight priority of the surge sensitivity command is increased. The weight coefficient adjustment function uses an S-shaped curve for smooth transition, avoiding abrupt changes in the optimization target.

[0109] When recalculating fitness values ​​using weight adjustment coefficients, the algorithm reconstructs the weighted calculation model. The adjusted weight coefficients are then incorporated into the fusion formula for three indicators: resistance difference, discharge current deviation, and temperature rise / fall, generating a fitness evaluation standard adapted to the current fault characteristics. This mechanism dynamically focuses the genetic population's evolutionary direction on the most urgent fault types, optimizing the targeting of command generation.

[0110] The embodiments of the present invention are as follows:

[0111] Example 1: Application of new energy power plants;

[0112] This system is deployed in a 35kV photovoltaic power station single-core cable network. The intermediate joint module adopts a stepped silver-plated contact surface, and the contact resistance monitoring unit maintains the monitored value below 0.08Ω; the 70mm grounding cable module... 2 The soft copper stranded wire collects the discharge current in real time through a current sensing unit, and the data is transmitted to the control module via an RS485 bus. During operation, when the fault mode library identifies abnormal resistance signals, the genetic algorithm unit integrates the temperature rise signal to output a crimping adjustment command. The hydraulic actuator dynamically adjusts the oil pressure to eliminate resistance fluctuations caused by contact surface oxidation. The system operated continuously for 12 months without sheath breakdown faults, verifying the effectiveness of the adaptive contact pressure adjustment.

[0113] Example 2: Offshore wind farm application;

[0114] This is a 66kV wind farm cable connector designed for use in humid, salt-spray environments. The grounding box module features an IP67 sealed moisture-proof structure, with an inner copper-nickel alloy shielding layer to suppress electromagnetic interference. The surge protection unit's MOV varistor array records surge frequency signals. When the surge frequency exceeds limits and the temperature rise exceeds the standard within 10 minutes, the genetic algorithm unit outputs a surge sensitivity command, lowering the conduction voltage threshold and accelerating the discharge of impact energy. The action counting unit statistically shows a shortened surge event response time and a significantly reduced risk of sheath overvoltage damage.

[0115] Example 3: Application in dense industrial power transmission areas;

[0116] In 110kV power lines within densely cabled industrial areas, the control device module's storage unit continuously records historical discharge current curves. When the current value is below 60% of the rated value for 24 consecutive hours, the genetic algorithm unit retrieves the aging curve of the soft copper stranded wire and generates a three-level early warning command: the first level triggers an alarm on the grounding box indicator light; the second level sends an SMS to the maintenance terminal; and the third level links to the power grid dispatch system. This tiered mechanism accurately locates three cable aging points, improving maintenance efficiency and preventing cascading failures caused by grounding failures.

[0117] Example 4: Application in high-altitude temperature difference environments;

[0118] In high-altitude areas, the temperature difference in 220kV cable networks reaches 40℃. The temperature sensing unit of the grounding box module monitors extreme temperature rises. A fault mode library correlates temperature rise thresholds with current overload fault types. When the temperature rise signal continuously exceeds the limit, the genetic algorithm unit calculates the fitness value with weights, outputs maintenance warning commands, and optimizes crimping adjustment commands. The hydraulic actuator adjusts the pressure in stages to compensate for the thermal expansion and contraction deformation of the metal sheath. Operational data shows that the joint temperature rise stabilizes within 15℃, resolving the contact pressure imbalance problem caused by temperature differences.

[0119] The technical approach of this invention to solve the problems of grounding failure and cable sheath breakdown is based on a multi-level collaborative control mechanism. The intermediate joint module adopts a stepped silver-plated contact surface design to expand the effective conductive area and reduce the initial contact resistance; the contact resistance monitoring unit collects the resistance signal between the metal sheaths in real time to identify the risk of contact surface oxidation or loosening at an early stage. The multi-strand soft copper stranded wire material of the grounding cable module improves bending flexibility and current discharge capacity, and combined with the current sensing unit to monitor the attenuation trend of the discharge current, it blocks the accumulation of circulating current caused by the deterioration of the grounding channel.

[0120] The temperature sensing unit and surge protection unit of the grounding box module work together. The temperature sensing unit detects local temperature rise anomalies, while the action counting unit records the frequency of surge events. The dual signals are fused to identify the coupling state of overload and voltage impulse. The control device module associates physical signals with fault types through mapping rules in the fault mode library: resistance threshold ranges are mapped to contact surface oxidation faults, temperature rise threshold ranges are mapped to current overload faults, and surge frequency threshold ranges are mapped to voltage impulse faults, thus constructing a fault feature identification benchmark.

[0121] The genetic algorithm unit dynamically generates optimization instructions based on the real-time signal-fault mapping relationship. When the resistance signal exceeds the limit, it integrates the temperature rise and discharge current signals to generate hydraulic compensation parameters, driving the hydraulic actuator to adjust the contact pressure and rebuild a reliable electrical connection. When the temperature rise and surge frequency exceed the standard, it modifies the conduction threshold of the metal oxide varistor to accelerate the discharge of impact energy. When the discharge current remains low, it compares the aging curve of the soft copper stranded wire to generate a graded early warning and trigger precise maintenance. This closed-loop control breaks the fault chain of increased contact resistance, circulating current accumulation, local overheating, and insulation deterioration, suppressing the risk of sheath breakdown.

[0122] This invention achieves dynamic pressure optimization at the metal sheath contact surface to maintain a low resistance state, adaptive adjustment of the surge protection threshold to suppress transient overvoltage damage, and predictive maintenance of grounding cable aging trends. Through improved physical structure, multi-source signal fusion, and intelligent decision-making and execution across the entire chain, the system significantly reduces the failure rate of high-voltage cable joints.

Claims

1. A high voltage single core cable joint grounding system, characterized in that, Comprise: The intermediate joint module, the metal sheath contact surface of the intermediate joint module is a stepped structure and is plated with silver on the surface, and the stepped structure is embedded with a contact resistance monitoring unit; The grounding cable module is made of soft copper stranded wire material, and the outer sheath of the grounding cable module is provided with a monitoring hole and is internally provided with a current sensing unit; The grounding box module is internally provided with a temperature sensing unit and a surge protection unit, and the surge protection unit is configured with an action counting unit; The control device module is connected with the contact resistance monitoring unit, the current sensing unit, the temperature sensing unit and the action counting unit through a communication bus; The control device module is configured to: Collect the resistance signal of the contact resistance monitoring unit, the leakage current signal of the current sensing unit, the temperature rise signal of the temperature sensing unit and the surge frequency signal of the action counting unit; Retrieve the pre-stored historical data and the fault mode library stored therein, wherein the fault mode library includes a resistance threshold, a temperature rise threshold and a fault type mapping relationship; Input the collected signals, the historical data and the fault mode library into a genetic algorithm unit, and the genetic algorithm unit outputs a crimping adjustment instruction, a surge sensitivity instruction or a maintenance warning instruction; The control device module executes the crimping adjustment instruction to adjust the oil pressure of the hydraulic actuator, executes the surge sensitivity instruction to modify the turn-on voltage threshold of the surge protection unit, and executes the maintenance warning instruction to push the maintenance notification.

2. The high voltage single core cable joint grounding system according to claim 1, characterized in that, Further comprise: the contact resistance monitoring unit adopting four-terminal detection principle, contacting the metal sheath stepped surface through the probe array arranged on the stepped surface of the stepped structure; The contact resistance monitoring unit obtains the resistance value based on the probe contact data; The communication bus is an RS485 bus transmitting Modbus RTU protocol, realizing data transmission of each monitoring unit and the control device module in claim 1.

3. The high voltage single core cable joint grounding system according to claim 2, characterized in that, The control device module includes a microprocessor and a storage unit; The storage unit continuously records and forms the historical change curves of the resistance signal, the leakage current signal, the temperature rise signal and the surge frequency signal during system operation, constituting the pre-stored historical data; The microprocessor executes the operation of the genetic algorithm unit.

4. The high voltage single core cable joint grounding system according to claim 3, characterized in that, The genetic algorithm unit is configured to: Encode the crimping adjustment instruction, the surge sensitivity instruction and the maintenance warning instruction into genetic gene sequences, generate multiple sets of genetic gene sequences to form an initial population, calculate the fitness value of each set of genetic gene sequences according to the collected signals and the pre-stored historical data, the fitness value is the weighted calculation result of the resistance difference, the leakage current deviation and the temperature drop amplitude, select the top 20% individuals with the highest fitness value into the next generation population, and implement gene crossover operation and gene mutation operation on the next generation population, and when the iteration number reaches 50 times or the fitness value change amount is less than 5%, output the optimal genetic gene sequence as the control instruction.

5. The high voltage single core cable joint grounding system according to claim 4, characterized in that, The gene crossover operation includes: selecting a single-point crossover position in the genetic gene sequence, and exchanging the crimping force parameter corresponding gene segment and the surge sensitivity parameter corresponding gene segment; The genetic variation operation includes: randomly selecting 10% of the gene segment, applying a ±0.2MPa disturbance to the crimping force parameter, or applying a ±0.05 times rated voltage disturbance to the corresponding conduction threshold of the surge sensitivity parameter.

6. The high voltage single core cable joint grounding system of claim 5, wherein, Also includes: When the resistance signal exceeds the resistance threshold in the fault mode library, the genetic algorithm unit is configured to: Fusing the temperature rise signal and the discharge current signal generates a dynamic pressure compensation coefficient, calculates a hydraulic compensation parameter based on the dynamic pressure compensation coefficient, and outputs a crimping adjustment instruction to the hydraulic actuator.

7. The high voltage single core cable joint grounding system according to claim 6, characterized in that, Also includes: When the temperature rise signal reaches the temperature rise threshold of the fault mode library and the surge frequency signal exceeds 5 times within 10 minutes, the genetic algorithm unit outputs a surge sensitivity instruction, which modifies the conduction voltage threshold of the MOV element in the surge protection unit, so that the conduction voltage threshold is reduced by 15% of the original threshold.

8. The high voltage single core cable joint grounding system according to claim 7, characterized in that, Also includes: When the discharge current signal is continuously lower than 60% of the rated value for 24 hours, the genetic algorithm unit calls the soft copper stranded wire aging curve recorded in the storage unit, generates a warning level parameter according to the deviation of the aging curve from the discharge current signal, and outputs a multi-level maintenance warning instruction corresponding to the level.

9. The high voltage single core cable joint grounding system according to claim 8, characterized in that, Also includes: The grounding box module adopts a sealed moisture-proof structure with an IP65 protection level, and the inner wall of the grounding box is provided with a copper-nickel alloy electromagnetic shielding layer with a thickness of 0.5mm; The surge protection unit includes a discharge channel assembly composed of an array of MOV voltage-sensitive resistors; The action counting unit records the number of conduction events of the array of MOV voltage-sensitive resistors in real time and serves as a source of surge frequency signal.

10. The high voltage single core cable joint grounding system of claim 9, wherein, Also includes: The fault mode library stores the following through pre-defined mapping rules: The contact resistance threshold interval corresponds to the contact surface oxidation fault type, the temperature rise threshold interval corresponds to the current overload fault type, and the surge action frequency threshold interval corresponds to the voltage impact fault type; The genetic algorithm unit is configured to extract the deviation amount of the threshold interval in the mapping relationship between the real-time acquisition signal and the fault type, generate an adaptability weight adjustment coefficient based on the deviation amount, and re-calculate the adaptability value by applying the weight adjustment coefficient.

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