725 results about "INSULATION FAILURE" patented technology

The invention relates to a low-voltage motor insulation resistance online monitoring and early warning method, system and device and a medium. The method comprises the following steps: firstly, acquiring multi-dimensional operation data through a data acquisition link to form an original monitoring data set; preprocessing the original monitoring data set, and focusing core information through dimension reduction processing to obtain a key parameter set; and then inputting the key parameter set into a dynamic correlation model constructed based on a long short-term memory network, and outputting a prediction result of the variation trend of the insulation resistance value along with time and the deterioration degree quantification. And finally, carrying out early warning analysis based on a prediction result, and generating early warning fault features in combination with a real degradation judgment process. According to the method, the insulation resistance trend and the degradation degree are accurately predicted, the defect of insufficient real-time performance of off-line detection is overcome, the accuracy and the pertinence of fault early warning are improved, and equipment shutdown and safety risks caused by insulation faults are effectively reduced.

The invention relates to the technical field of power equipment fault diagnosis, in particular to a transformer overheating fault intelligent diagnosis system based on a physical information neural network. According to the invention, physical constraint filtering is carried out on signals through the adaptive noise suppression module; a loss function fusing a heat conduction equation, a gas decomposition kinetic equation and an insulation aging kinetic equation is constructed through a physical information neural network, and coupling modeling of temperature and gas and collaborative prediction of the aging state of insulation paper are achieved; spatial topological features and time sequence features are extracted through a multi-modal feature fusion module, and cross-modal association is established by adopting an attention mechanism; predicting a future feature trajectory through a fault evolution prediction module and outputting hierarchical early warning; and finally, outputting fault types, severity and maintenance suggestions. According to the method, a physical mechanism and data intelligence are deeply fused, advanced early warning and accurate positioning of an overheat fault are realized, and meanwhile, the blank that insulation failure cannot be pre-judged in the prior art is filled.

The invention belongs to the technical field of heating devices, and discloses a thick film heater adopting an indirect heat dissipation technology, which comprises a main shell and a film heating plate, the film heating plate is connected with a radiator, the radiator is connected with heat dissipation fins, the inner side of a heating cavity is connected with a sealing element, and the main shell is connected with a water inlet pipe and a water outlet pipe. A heat dissipation water channel is defined by the heat dissipation device, the heat dissipation fins and the water closing plate, the main shell is connected with a PCBA circuit control board, and the main shell is connected with a low-voltage connector and a high-voltage connector. According to the technical scheme, due to the arrangement of the radiator and other structures, the situation that the radiating fins are directly welded to the heating plate to cause deformation of the heating plate to affect the heating effect or insulation faults is avoided, the radiator and the radiating fins are integrally die-cast, the heat exchange area is greatly increased, the heat exchange coefficient is increased, the heater cannot be locally overheated, and the service life of the heater is prolonged. The tolerance robustness of bubbles existing in a whole vehicle cooling liquid system is enhanced, and the use stability of the heater is greatly improved.

The present invention relates to the technical field of batteries, and discloses a secondary battery, which comprises: a housing having a cavity; the battery cell is arranged in the cavity, and the battery cell comprises a battery cell body and a tab; the pole column is arranged on the shell; the adapter piece comprises a tab connecting part and a pole connecting part, and at least part of the tab is arranged opposite to the tab connecting part after the tab is led out of the battery cell body; and in the thickness direction of the battery cell, the thickness of the pole connecting part is L1, the thickness of the tab is D, in the thickness direction of the battery cell, the thickness of the battery cell is L, the width of the pole connecting part is L1, the width of the tab connecting part is L2, and (L1 / L2) * (D / (L-L2)) is 0.008-1. By controlling (L1 / L2) * (D / (L-L2)) to be within a range of 0.008-1, a space is reserved for a bending corner of the tab, so that the tab is prevented from being broken due to scratching of the shell, and even short circuit and insulation failure between the tab and the shell are avoided; and meanwhile, the over-current capability is considered, the balance of current transmission is realized, and excessive temperature rise of the battery is avoided.

The invention relates to the technical field of electrical measurement and power system monitoring, in particular to a cable insulation fault detection method. The method comprises the following steps: measuring an electric field signal and constructing an electric field distribution model in a cable to obtain a signal mapping result of a cable insulation state; the signal mapping result of the cable insulation state is mapped to a frequency domain, smoothing processing is carried out, multi-scale analysis is carried out on the signal after smoothing processing, fault features of the cable are extracted, the insulation state of the cable is quantified, the probability that the cable has an insulation fault is calculated, and a basis is provided for fault early warning and maintenance. The problems that most of traditional insulation fault detection methods depend on single electrical or spectral characteristic detection, so that detection information is incomplete; the stability is poor, and misjudgment or missed judgment is easily caused; in some methods, power failure or direct contact with a cable is needed for measurement, and continuous operation of the cable is affected. And complex electric field distribution and dynamic change thereof in the cable are difficult to accurately describe, and the fault development trend is difficult to predict.

A method and apparatus for frequency domain diagnosis of a power cable defect on the basis of a cross-interconnection box structure. The method comprises: by means of a wiring terminal intersecting a three-phase shielding layer of a cross-interconnection box, injecting a broadband signal, and obtaining a time domain result (S101); according to the time domain result being mapped into a frequency domain, performing analysis, and obtaining impedance spectrum results of a left end and a right end of an injection cross-interconnection box (S102); and, according to the impedance spectrum results, diagnosing hidden danger defects of an outer sheath and a main insulation in a three-phase cable (S103). The present disclosure solves the problem in the related technology that traveling wave reflection method diagnosis strategies cannot avoid direct connection to a cable core wire when identifying a main insulation fault in a cable, which limits the application scenarios of a traveling wave injection method to only being applicable to inspection before a cable has been put into operation and cable defect assessment after a cable fault has occurred. Additionally, the present disclosure solves the problems of high device requirements and testing costs, leading to the inability to meet daily operation and maintenance inspection requirements of cables and various test scenarios.

The invention relates to the technical field of power distribution station fault early warning, in particular to a rapid fault early warning method and system for a large-scale power distribution station, and the method comprises the steps: comparing the maximum amplitude difference between electromagnetic wave signals of any two sensors, combining the interference coefficient mean value of the electromagnetic wave signals in all sensors, determining the amplitude deviation, and determining the maximum amplitude difference; the maximum partial discharge signal is screened out by combining the distance between any two sensors; the partial discharge index is determined by analyzing the energy of the maximum partial discharge signal in each frequency interval and the dispersion degree of the maximum amplitude of the electromagnetic wave signals in all the sensors in each target period and combining the proportion of the number of all the target periods in the total number of the power frequency periods. And performing fault early warning on the to-be-tested switch cabinet in the large-scale power distribution station. The invention aims to improve the detection precision of the insulation fault of the switch cabinet in the large-scale power distribution station.

The invention discloses a photovoltaic system night insulation impedance detection method, which comprises the following steps: before a photovoltaic system works at night, power is taken from a power grid through a power taking framework to supply power to a bus cathode of the system, so that ground insulation impedances of positive and negative electrodes of all photovoltaic group strings and the power taking framework form a grounding loop; the ground insulation resistance of the direct current side of the system is calculated by measuring the voltage of the power taking framework; when the photovoltaic system works at night, ground insulation fault positioning is carried out by controlling the power taking framework and the switching tubes of the DC / DC units. The beneficial effects of the invention are that the system can achieve the online detection of the night insulation resistance of a photovoltaic system, and the whole detection architecture is simple in structure, and even does not need to modify an existing hardware circuit, thereby effectively reducing the cost.

The invention relates to the technical field of high-voltage electrical equipment, and particularly discloses a high-insulating-property thermoplastic sleeve and a method for preparing the same based on a co-extrusion process, the surface of a nonlinear layer is wrapped with an insulating material, so that the corona discharge phenomenon is avoided; and meanwhile, the same thermoplastic material is adopted as the insulating layer (including the first thermoplastic layer and the second thermoplastic layer) material and the base material of the nonlinear layer, so that no obvious interface exists between the insulating layer and the nonlinear layer, charge accumulation is avoided, insulation failure is avoided, the insulation and voltage resistance of the sleeve is improved, and the operation reliability is improved.

The invention discloses an insulation fault edge self-healing method and device for a power conversion system, and belongs to the technical field of fault diagnosis and automatic maintenance of power electronic equipment, and the method comprises the steps: obtaining multi-modal sensing data, synchronously collected by a multi-modal sensor array, of the power conversion system; a preset lightweight CNN-Transform hybrid model is used to process the multi-modal sensing data, and a feature vector of each modal is obtained; fusing each modal feature vector by adopting a dynamic weight attention mechanism to obtain a fused fault feature vector; classifying the fused fault feature vectors based on a fault classifier, and determining a fault level; and according to the determined fault level, sending a corresponding control instruction to an execution mechanism, and triggering a hierarchical self-healing action. According to the invention, fault identification and self-healing decision can be rapidly completed, and the accuracy of fault detection is effectively improved.

The invention discloses an insulation residual life prediction algorithm and device based on real-time temperature acquisition and a medium, and relates to the technical field of new energy automobiles, and the method mainly comprises the steps: constructing an offline insulation failure database through an accelerated thermal aging experiment of a twisted pair sample, and recording the PDIV of a target motor at a brand new state room temperature as an initial PDIV0; based on the off-line insulation failure database, obtaining the aging slope of the PDIV decaying along with the aging time at each motor winding temperature and a corresponding aging curve; according to the mapping relation between the PDIV and the motor winding temperature, obtaining an insulation threshold voltage corresponding to the current motor winding temperature under the correction of a temperature correction coefficient; and based on the current PDIV0 and the insulation threshold voltage, substituting the aging curve corresponding to the current motor winding temperature to obtain and output the difference value of the corresponding insulation failure time of the two as the insulation residual life. The method can accurately capture the initial characteristics of insulation aging, the early warning time is advanced, and the timeliness is improved.

The invention relates to the technical field of on-line monitoring, in particular to an insulation fault on-line monitoring method and system for a medical IT system control cabinet. The method comprises the following steps: selecting a non-integer frequency multiplication detection frequency according to equivalent ground distributed capacitance in a previous monitoring period, and superposing the non-integer frequency multiplication detection frequency with a fundamental frequency to form a composite signal injection system; collecting signals to calculate a voltage instantaneous harmonic distortion rate change gradient, and selecting a time window to split the leakage current according to the change gradient; on the basis of dispersion estimation signal-to-noise ratio weighted fusion current vectors, insulation resistance and distributed capacitance are calculated; constructing a four-dimensional original feature vector composed of the insulation parameter, the phase difference and the intermodulation component energy; constructing a diagonal weighting matrix based on the resistance-capacitance ratio and the gradient to transform a feature vector, and determining the fault attribution through the Mahalanobis distance calculation with the fault template library. According to the scheme, harmonic interference can be avoided, calculation stability can be improved, insulation instantaneous sudden change can be quickly responded, and different fault types can be accurately distinguished to guide maintenance.

The invention relates to a ring main unit intelligent detection and fault early warning method and system. The method comprises the following steps: deploying an ultrahigh frequency sensor, an infrared thermal imager, an ultraviolet sensor and a high-frequency current transformer, and synchronously acquiring multi-modal data such as partial discharge, temperature distribution, corona discharge and grounding current of the ring main unit; carrying out feature extraction on the collected data, wherein the feature extraction comprises a time-frequency statistical feature and a temperature-load correlation feature of the partial discharge signal; the Dempster-Shafer evidence theory is utilized to carry out fusion calculation on the multi-source feature evidence, and confidence coefficients for insulation degradation, poor contact, arc faults and other fault types are obtained; arc fault prediction is carried out in combination with a long-short-term memory network model; and finally executing a grading early warning strategy according to the fault confidence. The problems of low detection reliability and fault early warning lag of a single sensor are solved, early accurate diagnosis and predictive maintenance of the insulation fault of the ring main unit are realized, and the operation safety and reliability of power equipment are remarkably improved.

The invention provides an insulation fault detection method and device of a power battery, equipment and a medium. The method comprises the steps of obtaining multiple pieces of state time sequence data of the power battery; wherein the multiple pieces of state time sequence data comprise insulation resistance value time sequence data, collected by an insulation monitoring unit, of a battery module in the power battery and sensor time sequence data, collected by each preset sensor, of the power battery; performing weighted data fusion on the plurality of pieces of state time sequence data, and determining an insulation health score of the power battery; and comparing the insulation health score with a plurality of preset score thresholds, and determining an insulation fault detection result of the power battery. Through the method and the device, the degradation trend of the insulation performance can be recognized earlier, the sensitivity and the accuracy of fault detection are improved, safety accidents caused by lagging alarm of insulation faults are effectively avoided, and the operation safety and the reliability of a power battery system are remarkably improved.

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.

The invention discloses a cable accessory insulation failure simulation analysis method based on a multi-physics field aging test, and belongs to the technical field of electric power analysis. Establishing a silicone rubber stress relaxation constitutive equation; establishing an interface defect probability density function; establishing an insulation failure criterion equation; combining a silicone rubber stress relaxation constitutive equation, an interface defect probability density function and an insulation failure criterion equation to obtain an electricity-heat-force combined aging simulation model, and outputting an interface pressure attenuation rate, a partial discharge initial probability and an insulation residual life three-dimensional cloud picture according to interface air gap electric field data and a critical aging state threshold value. According to the method, the electric-thermal-mechanical multi-physical field coupling model is constructed, and the influence of interaction of each physical field on insulation aging is comprehensively considered, so that the technical effect of accurately presenting the full view of the insulation aging process under multi-stress coupling is realized, and the problem that the insulation aging process under multi-stress coupling is difficult to accurately describe in the prior art is solved.

The invention discloses an on-line insulation monitoring system and method for a national railway vehicle, and relates to the technical field of on-line insulation monitoring, and the system comprises a detection signal injection module which is used for injecting a preset broadband active detection signal, and synchronously collecting a response signal set transmitted through a vehicle body grounding network; the fingerprint feature construction module is used for constructing network fingerprint features in a current insulation state; the spatial distribution atlas acquisition module is used for carrying out inversion calculation to obtain an admittance spatial distribution atlas of the whole vehicle; and the insulation abnormal area identification module is used for identifying an insulation abnormal area. According to the invention, the technical problems of long troubleshooting time and poor accuracy caused by incapability of online real-time monitoring of the insulation state of the vehicle body grounding network of the national railway vehicle and low abnormal area positioning precision in the prior art are solved, and online monitoring of the insulation state of the vehicle body grounding network of the national railway vehicle and accurate positioning of the abnormal area are realized. And the efficiency and the accuracy of insulation fault checking are improved.

The utility model discloses a battery, electric equipment and an energy storage device, and relates to the technical field of energy storage and power batteries. The battery comprises a plurality of battery monomers, a metal bandage and an insulating part, the plurality of battery monomers are arranged side by side, and each battery monomer comprises a metal shell; the metal bandage bypasses the plurality of battery monomers and is used for binding the plurality of battery monomers; the insulating part is connected to the battery monomer or the metal bandage, and at least part of the insulating part is positioned between the battery monomer and the metal bandage; the insulation resistance value between the metal bandage and each metal shell is greater than or equal to A * B * 1000 ohm, A is the nominal voltage of the single battery, and the unit is V; b is the series connection number of the single batteries, and the unit is one. According to the technical scheme provided by the utility model, the problem that insulation failure is easy to occur between the metal bandage and the battery monomer during thermal runaway can be improved.

The invention relates to the technical field of power equipment on-line monitoring and fault diagnosis, and discloses a converter transformer bushing end screen voltage abnormity detection device and early warning method.The method comprises the steps that voltage data are collected through a wireless intelligent sensor, soft synchronization and self-adaptive windowing are achieved through a commutation notch feature locking mechanism, and a preprocessing signal is output; topological correlation clustering is executed to construct a virtual health reference, a dynamic residual sequence is extracted through time domain difference, and system side and equipment side features are decoupled; constructing a variational mode decomposition model, and calculating a characteristic entropy value of the intrinsic mode function; and comparing the entropy value with a threshold value, triggering an active impedance disturbance verification mechanism, controlling a sensor to access a load and comparing an actual voltage drop rate with a theoretical voltage drop rate, and determining an insulation degradation or poor contact fault. High-precision synchronization can be achieved without a hardware clock, and the problems that weak fault features are difficult to extract and virtual connection and insulation faults are difficult to distinguish in a high-impedance loop are effectively solved.

The invention discloses an insulation resistance detection method, system and device of a photovoltaic power generation system and a medium, and relates to the technical field of insulation resistance detection of the photovoltaic power generation system. The method comprises the steps of obtaining a ground insulation resistance value of the photovoltaic inverter, and determining an insulation fault level according to the ground insulation resistance value of the photovoltaic inverter. And whether MPPT-level insulation impedance detection is carried out is determined according to the insulation fault level. If MPPT-level insulation impedance detection is carried out, the fault type is determined, and the fault type comprises a negative electrode grounding fault or a non-negative electrode grounding fault. And under the condition that the fault type is a non-cathode grounding fault, sequentially disturbing the plurality of MPPT branches, and determining a grounding MPPT branch. And determining the photovoltaic module with the insulation impedance fault in the grounded MPPT branch. According to the invention, fault positioning is carried out according to the sequence from the whole machine to the MPPT branch to the photovoltaic module, and the fault positioning precision is high.

The invention provides a ground insulation resistance detection circuit, a detection method and a product, which are applied to a detection scene of ground insulation resistance of a direct current side of a non-isolated high-voltage energy storage converter. According to the ground insulation impedance detection circuit provided by the embodiment of the invention, a complex isolation circuit in an isolation type scheme is not needed, an additional bridge arm resistor in a non-isolation type scheme is also avoided, the detection circuit is constructed through a small number of resistors, switches and voltage acquisition modules, the number of devices and the occupation of PCB space are reduced, the design and manufacturing cost can be effectively reduced, and the detection circuit is suitable for large-scale popularization and application. And the compact layout requirement of the non-isolated high-voltage energy storage converter is met. On the basis, the embodiment of the invention further provides a ground insulation impedance detection method, the voltage acquisition module stably collects the first voltage and the second voltage through on-off of the switch, whether the risk of insulation failure exists or not is judged, the situation of sampling signal distortion in a non-isolation scheme can be reduced, and the detection precision is effectively improved.

The invention relates to the technical field of drilling engineering equipment, in particular to a pipe cable branching glue pouring sealing structure and method.The pipe cable branching glue pouring sealing structure comprises a wrapping part and an extension part; a wrapping cavity wrapping the end part of the pipe cable is formed in the wrapping part; the extension part is arranged on the end face of the wrapping part and surrounds the wrapping cavity, and the height of the wrapping cavity can be increased through the extension part; a drainage channel is formed in the end face of the wrapping part. The space capable of being filled with glue is expanded through the extension part, so that the height of the filled glue can be higher than the height of the end face of the wrapping part, even if the glue is cured and contracted, the glue is prevented from forming a recess at the end of the wrapping part, the possibility of water accumulation is reduced, and the insulating capacity of the branched cable is ensured; and the probability of the problems of insulation failure, short-circuit fire, out-of-control equipment and the like caused by sealing failure of the branching part of the pipe cable is also reduced.

The invention relates to an insulation fault identification method and system, electronic equipment, a medium and a product, and belongs to the technical field of electronics. The method comprises the steps that when the insulation resistance value of a vehicle is smaller than a preset first resistance value, whether the vehicle is subjected to direct current charging operation within a preset first time period or not is judged; if the direct current charging operation is not carried out on the vehicle, whether a first difference value between the maximum value and the minimum value of the insulation resistance value in a preset second time period is larger than a preset second resistance value or not is judged; if the first difference value is not larger than the preset second resistance value, whether the air conditioner of the vehicle is used or not within a preset third time period is judged; if the air conditioner is used, the insulation fault type of the vehicle is determined according to the temperature parameters related to the air conditioner. By analyzing the big data related to the vehicle insulation fault, the insulation fault type can be quickly determined, so that the insulation fault positioning efficiency is improved, the troubleshooting period is shortened, the economic loss caused by continuous existence of the fault is reduced, and the maintenance cost is reduced.

The invention discloses a power equipment insulation fault early warning method and system based on machine learning, and relates to the technical field of fault early warning, and the method comprises the following steps: constructing a time sequence connection relation graph of discharge pulses based on a multi-point discharge time sequence set in an insulation structure; identifying a discharge closed loop based on the time sequence connection relation graph, and constructing a closed loop evolution sequence according to a time sequence; by taking the evolution sequence as a training target, constructing a machine learning prediction model for predicting the closing trend of the discharge path; and based on the prediction model, predicting a discharge path closing state of the target power equipment during future operation, and outputting an insulation fault early warning signal based on a prediction result. According to the invention, the insulation fault early warning signal is generated by identifying the closed loop and predicting the closing trend of the discharge path, so that the problem that the prior art only depends on the discharge intensity and is difficult to accurately warn the insulation fault is solved.

The invention relates to the technical field of ring main unit engineering, in particular to a state evaluation method and system for a gas insulation environment-friendly ring main unit, and the method comprises the steps: obtaining space probe distribution coordinates and gas concentration data in the environment-friendly ring main unit, and generating a leakage gas three-dimensional concentration matrix according to the leakage gas three-dimensional concentration matrix; constructing a gas concentration distribution prediction model matched with the environment-friendly ring main unit, inputting the leakage gas three-dimensional concentration matrix and the geometric parameters of the cabinet body into the gas concentration distribution prediction model, and outputting to obtain predicted gas concentration distribution; generating a gas leakage behavior parameter, and generating an insulation failure probability and an electric ignition risk index; and generating an insulation performance evaluation index, and generating state evaluation of the environment-friendly ring main unit according to the insulation performance evaluation index. According to the method, the gas leakage behavior is accurately simulated, so that the insulation failure probability and the electric ignition risk index are quantified, and the accuracy of state evaluation of the ring main unit is greatly improved.

The utility model relates to the technical field of shield pumps, in particular to an axial flux motor shield pump. According to the utility model, metal parts such as the stator and rotor cores, the windings and the permanent magnets are isolated from a conveying medium through an integrated injection molding means of the stator shielding sleeve with a special structure and the rotor assembly, so that the problems of corrosion of the metal parts, insulation failure and the like caused by difficulty in isolation from the conveying medium when the axial magnetic flux motor is applied to a shield pump are solved; further, the axial flux motor is applied to the shield pump; meanwhile, rotor assembly unilateral magnetic pulling force generated by the single-stator single-rotor axial flux motor structure can balance part of axial force generated when the impeller operates, the axial force borne by the bearing is reduced, the service life of the bearing is prolonged, and then the service life of the whole pump is prolonged.

One aspect of the invention relates to a bidirectional on-board charger 2 for a vehicle 1, comprising:a bidirectional AC-to-DC converter 8 designed to supply power to an electrical power supply socket 6 for an external electrical device;means for detecting an electrical insulation fault 9, connected to a phase line 12 and to a neutral line 13 of said electrical power supply socket 6; a switch 16 arranged on said phase line 12; a switching means 18 designed to control the switch 16 between a first position P1 in which the means 9 are connected to the socket 6 and a second position P2; a resistor 20 which, when the switch 16 is in the second position P2, is electrically connected to the switch 16 and to a ground 10 of the vehicle.

The invention relates to the technical field of photovoltaic inverter grid connection, and discloses a photovoltaic panel assembly insulation impedance fault positioning method, a storage medium and a system. Comprising the steps of collecting voltage between positive and negative electrodes of an inverter under first voltage, voltage to ground of the negative electrode of the inverter and a direct-current component of leakage current of an output end, close to a power grid side, of the inverter; collecting the voltage between the positive electrode and the negative electrode of the inverter under the second voltage after voltage disturbance, the voltage to ground of the negative electrode of the inverter and the direct-current component of the leakage current of the output end, close to the power grid side, of the inverter; calculating a first insulation resistance value corresponding to the plurality of photovoltaic panel assemblies under the first voltage, and calculating a second insulation resistance value of the plurality of photovoltaic panel assemblies under the second voltage; and according to the first insulation resistance value and the second insulation resistance value, positioning the photovoltaic panel assembly with the insulation resistance abnormity. According to the invention, the accurate positioning of the insulation fault of the photovoltaic panel assembly level is realized, and the specific photovoltaic panel assembly with the insulation abnormity can be accurately identified from the series photovoltaic string.

The invention relates to the technical field of new energy automobile high-voltage safety, and particularly provides a new energy automobile high-voltage safety protection method and system based on multistage linkage outage, and the method comprises the steps: a sensor layer continuously collects high-voltage system parameters, and forms an original data stream; the high-voltage system parameters comprise insulation resistance, collision acceleration, battery pack pressure, temperature and the like; original data flows are processed by a multi-level diagnosis center, and fault level judgment is obtained by combining fault codes and timestamps recorded by a fault latch memory through multi-source data fusion and threshold comparison; and an execution instruction is formed through fault level judgment, and an execution mechanism is driven to perform corresponding power-off operation. The system comprises a data flow acquisition module, a diagnosis central processing module and a power-off operation execution module. According to the invention, when abnormal working conditions such as collision, insulation fault, short circuit and the like of the vehicle occur, a rapid, accurate and reliable high-voltage safety protection device is realized through multi-stage collaborative diagnosis and staged power-off.

The utility model belongs to the field of cable detection, and particularly relates to a calibration device of cable detection equipment, which comprises a shell, a voltage verification high-voltage input end is fixedly embedded in a position, close to the upper left corner, of the front side of the shell, and a voltage verification high-voltage ground input end is fixedly embedded in a position, close to the lower left corner, of the front side of the shell; the device can simulate an open circuit, a broken line, a high-resistance fault, a low-resistance fault, a flashover fault and the like. And functions, performance, technical indexes and the like of a cable fault flash tester, a high-voltage bridge, a high-voltage pulse generator and a high-voltage unit are calibrated and inspected. The device can also be used for training the measurement and judgment of a power cable fault, a main insulation fault and an outer sheath fault, a top plate is pressed downwards, an inclined surface of a clamping block extrudes the top of a shell, the clamping block automatically shrinks inwards, and after the top plate slides to a proper position on the inner wall of the shell, the clamping block is automatically clamped in a clamping groove under the support of a spring, so that the clamping block is fixed. The device can be conveniently disassembled and assembled, and the maintenance efficiency of use is improved.