723 results about "Insulation resistance" patented technology

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 belongs to the technical field of power distribution switches, and particularly discloses a test mechanism suitable for a switch cabinet handle, which comprises a substrate, the upper end of the substrate is fixedly connected with a plurality of support frames, the upper ends of the support frames are fixedly connected with a support plate, and the upper end of the support plate is provided with a transmission groove. A rotating assembly used for rotating the handle is arranged on the base plate corresponding to the transmission groove, a detection assembly used for detecting the insulation state of the rotating handle is arranged on the side, close to the rotating assembly, of the supporting plate, and when the handle rotates along with the second square rod, the first square rod, the transmission block and the trigger protruding block are driven to rotate synchronously. The trigger bump can instantly extrude the micro-touch switch, the power supply module and the resistance detector are started, through a detection loop formed by a lead, insulation resistance changes of the connection part of the handle and the square rod under the action of mechanical friction and stress in the rotation process are accurately captured, dynamic insulation data of the handle are captured, and an electrical property detection test of the handle is realized.

The invention relates to the technical field of cable fault positioning, in particular to a cable fault accurate positioning method based on multi-channel synchronous acquisition, which comprises the following steps: S1, constructing a multi-channel adaptive acquisition system which comprises a main controller, a multi-channel acquisition module, a synchronous control module and a data transmission module; s2, multi-channel data synchronous acquisition is carried out through the synchronous control module, wherein the multi-channel data comprises impedance data, temperature data, partial discharge signals and insulation resistance data; during use, through a multi-channel adaptive acquisition design, monitoring channels can be flexibly selected according to cable materials, operation years and environmental conditions, different aging fault characteristics are comprehensively covered, the fault omission ratio and the false alarm rate are reduced, different types of low-voltage cables are adapted, a synchronous scheme of constant-temperature crystal oscillator and hardware triggering is adopted, and the reliability of the system is improved. The method does not need to depend on a GPS / PTP time service module, is favorable for saving cost input, and eliminates environmental interference and single parameter false triggering.

The invention provides a photovoltaic system and an insulation resistance detection method thereof, the photovoltaic system comprises a plurality of photovoltaic modules, a plurality of low-voltage switches, a plurality of high-voltage switches and a detection control circuit, the low-voltage switches are connected with one or more photovoltaic modules to form a second photovoltaic module, and the high-voltage switches are connected with the detection control circuit. The high-voltage switches are connected with one or more second photovoltaic modules which are connected in parallel, and the detection control circuit is connected with the low-voltage switches and the high-voltage switches, controls the high-voltage switches to be turned off in sequence, controls the corresponding low-voltage switches to be switched to a second switch state, determines the faulted first photovoltaic module according to the insulation resistance of the photovoltaic system, and ends the operation. The method does not need to employ a mode of manually plugging and unplugging the string or changing the voltage of the string, can achieve the detection of all fault assemblies, improves the detection precision, and improves the detection range.

The embodiment of the invention relates to the technical field of data processing, and provides a cable insulation and loop detection method and a related device, and the method comprises the steps: inputting a reference test voltage to a to-be-detected object; acquiring a current signal flowing through the to-be-detected object to which the reference test voltage is applied; determining an initial insulation resistance value according to the reference test voltage and the current signal; obtaining correction environment parameters of the to-be-detected object; generating target correction information according to the correction environment parameters; and correcting the initial insulation resistance value by using the target correction information to obtain a target insulation resistance value, thereby improving the accuracy of performing cable insulation and loop detection on the to-be-detected object.

The invention discloses a transformer substation secondary equipment fault detection platform and an analysis method. The platform comprises a mobile bearing unit, an instrument integration unit, an integrated power supply and safety protection unit, an image acquisition unit and a data fusion analysis unit. The platform carries a relay protection tester, a mutual inductor comprehensive characteristic tester and an insulation resistance meter in an integrated manner, and is equipped with an image acquisition system, so that convenient movement and multi-source data acquisition of detection equipment are realized. And the data fusion analysis unit adopts a multi-modal fusion deep learning model to carry out collaborative analysis on the electrical detection data and the visual data, and outputs a diagnosis conclusion containing accurate fault positioning and basic causes through feature extraction and fusion. According to the method, the problems of low efficiency and inaccurate diagnosis caused by inconvenient equipment carrying and data isolated analysis in traditional debugging are effectively solved, and the intelligent level, the safety and the reliability of operation and maintenance of the secondary equipment of the transformer substation are remarkably improved.

The invention relates to the technical field of insulation degradation detection, in particular to an insulation characteristic degradation detection method for an underwater wet-plugging electric connector, which is characterized in that a multi-angle appearance image of the connector is acquired through a pressure-resistant underwater camera device, and the image quality and the recognition accuracy are improved by adopting a defogging and color correction technology. And further extracting defect characteristics such as cracks, corrosion and aging on the surface of the connector through an image by virtue of a graph neural network model, realizing automatic identification and positioning of defect types, and then executing a local electrical test on the identified defect region to obtain electrical parameters such as insulation resistance, capacitance value and medium absorption ratio. Image recognition information and electrical test data are constructed into a feature matrix, a fusion evaluation model composed of a logistic regression model and a weighted scoring mechanism is input, an insulation degradation degree value is output, and a detection result is generated, so that the accuracy of insulation detection of the underwater wet-plugging electric connector is improved, and the detection time is effectively shortened.

There is provided a circuit for monitoring an insulating property of a fuel cell stack, comprising: a low-frequency voltage source for negatively injecting a low-frequency signal only to a high-voltage bus of the fuel cell stack; a first resistor; and a second resistor; wherein the low-frequency voltage source, the first resistor and the second resistor are connected in series, and the low-frequency voltage source, the first resistor and the second resistor which are connected in series are connected with a high-voltage bus negative ground insulation resistor of the fuel cell stack in parallel; and the voltage on the first resistor can be measured so as to be used for determining the insulating property of the fuel cell stack. Therefore, the low-frequency voltage source only injects the low-frequency signal at the negative single side of the high-voltage bus, so that only the insulating property of the negative single side of the high-voltage bus is reduced, and the insulating property of the positive side of the high-voltage bus is not influenced.

The invention provides an insulation resistance detection method and system of an energy storage system and a storage medium, and relates to the technical field of safety monitoring of the energy storage system. The method comprises the following steps: monitoring the total voltage of the energy storage system; calculating the change rate of the total voltage; comparing the change rate with a preset rate threshold; when the change rate is smaller than a preset rate threshold value, calculating a first insulation resistance value by adopting an unbalanced bridge method based on the current total voltage, and outputting the first insulation resistance value as an effective insulation resistance value; and when the change rate is greater than or equal to a preset rate threshold value, calculating a second insulation resistance value by adopting an unbalanced bridge method based on the current total voltage, comparing the second insulation resistance value with a stored reference insulation resistance value, and selecting an effective insulation resistance value output this time according to a comparison result. According to the method, the defect that the traditional BMS insulation detection function is insufficient in adaptability in the application of the super capacitor is overcome, and the anti-interference capability and the operation safety of the system are enhanced.

The invention relates to the technical field of motor test equipment, in particular to a multifunctional motor test operation system and method, and the method comprises the steps: a parameter detection module synchronously collects voltage, current, frequency, temperature, vibration, insulation resistance and DC resistance parameters, and converts the parameters into electric signals; the data processing module carries out amplification, filtering and analog-to-digital conversion on the electric signal to obtain a measured value; the storage module stores the measured value; and the report generation module automatically generates a test run report containing parameter analysis and qualification conclusions through a preset template based on the stored value. The parameter detection module synchronously collects various parameters and converts the parameters into electric signals, the data processing module processes the signals to obtain accurate measured values, the storage module stores data, and the report generation module automatically generates a test run report containing analysis and conclusion based on the stored values. The problems that the function is single, data integration is difficult and report generation is tedious are solved, the testing efficiency and accuracy are remarkably improved, and manual errors are avoided.

The invention discloses a high-voltage motor pagoda structure direct insulation automatic detection device, which comprises a background system, a pagoda structure detection device and a display device, and is characterized in that the background system is electrically connected with the pagoda structure detection device and the display device; the appearance of the pagoda structure detection device is a pagoda structure, the upper end of the pagoda structure is a high-voltage current-limiting resistor fixedly sealed by a silicone rubber umbrella skirt structure, and the lower end of the pagoda structure is a metal shell. A motor running state input module, a relay output module, a microprocessor, a DC2500 / 5000V boosting module, a high-voltage isolation relay, a current sampling module and an analog-to-digital conversion module are arranged in the metal shell; the motor operation state input module, the relay output module, the microprocessor, the DC2500 / 5000V boost module, the current sampling module, the analog-to-digital conversion module and the high-voltage isolation relay are connected in sequence, and the device can automatically complete insulation resistance detection before the high-voltage motor is put into operation, does not need manual terminal disassembly and assembly, shortens the detection time, and improves the detection accuracy.

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 invention relates to a base metal high-voltage multilayer ceramic dielectric capacitor and a preparation method, the base metal high-voltage multilayer ceramic dielectric capacitor is formed by stacking and firing dielectric layers, and each dielectric layer comprises a dielectric layer and an electrode printed on the dielectric layer. The dielectric layer comprises the following raw materials: a BMYT main matrix, an NN material, magnesium oxide, manganous-manganic oxide, zirconium dioxide, calcium carbonate, strontium carbonate and rare earth oxide; through the raw material composition and the preparation method of the ceramic dielectric capacitor, the prepared ceramic dielectric capacitor has excellent performances of high dielectric constant, high voltage resistance, stable dielectric-temperature characteristic curve, low loss, high insulation resistance, long-term high-voltage reliability and the like under the condition of high dielectric thickness (30 microns before firing).

The invention provides a performance evaluation method and system for an electric connector insulator, and relates to the technical field of electric connectors, and the method comprises the steps: carrying out the electrothermal coupling simulation of the electric connector insulator, and determining a temperature distribution field of the electric connector insulator; according to the temperature distribution field, failure mechanism analysis is carried out on the electric connector insulator, and a carrier concentration change model of the electric connector insulator is constructed; constructing an insulation resistance degradation model based on the carrier concentration change model; obtaining measurement data of the electric connector insulator through an acceleration test; fitting parameters of the insulation resistance degradation model through a least square algorithm and a maximum likelihood estimation algorithm according to the measurement data; according to a parameter fitting result, constructing a reliability statistical function based on a weakest ring model; and according to the reliability statistical function, performing performance evaluation on the electric connector insulator. According to the method, the failure probability and the service life of the electric connector connecting piece under different working conditions can be accurately predicted.

The invention discloses a full-automatic life test system for an isolation device, which belongs to the field of reliability test of semiconductor devices, and comprises a system host used for providing a test environment and bearing a plurality of test channels; the high-low voltage isolation conversion module is arranged corresponding to each test channel and is used for switching between a high-voltage aging loop and an insulation resistance measurement loop of each channel; the real-time leakage current monitoring module is used for continuously monitoring the leakage current of each isolation device in the high-voltage aging process; the precision measurement and data acquisition module is used for carrying out insulation resistance measurement on the isolation device in a measurement mode; the central control and software system module is respectively connected with the high-low voltage isolation conversion module, the real-time leakage current monitoring module and the precision measurement and data acquisition module, and the central control and software system module is used for automatically triggering and controlling an insulation resistance measurement process according to leakage current data, judging the state of a device according to a measurement result, and outputting the state of the device. And aging and stopping of the test channel are managed.

The embodiment of the invention discloses a photovoltaic inverter insulation detection method and device and a photovoltaic inverter. The method comprises the steps that voltage parameters of an MPPT branch are acquired; the voltage parameters comprise a first voltage, a second voltage and a third voltage; based on the Kirchhoff's law, the ground insulation impedance of the MPPT branch is calculated according to the first voltage, the second voltage and the third voltage; and determining whether the MPPT branch has an insulation fault or not according to the ground insulation impedance of the MPPT branch. According to the scheme, the insulation resistance of each MPPT branch can be calculated one by one, so that the MPPT branch with the insulation fault can be quickly positioned.

The invention relates to the self-diagnosis of a circuit for measuring the insulation resistance of a battery system, the circuit having a first switch, which connects the positive terminal of the battery system to earth via a series-connected first comparator resistor, and a second switch, which connects the negative terminal of the battery system to earth via a series-connected second comparator resistor. Current measurements are made via the closed first switch to obtain a measured first current flow and via the closed second switch to obtain a measured second current flow, wherein at any one time only one of the two switches closed, the theoretical current flow via the switches is calculated on the basis of the voltage of the battery system and the size of the comparator resistor, and the measured current flow, is compared with the associated theoretical current flow, wherein an error signal is output and / or an error action is carried out when the result of the comparison is above or below a predefined reference value range.

The invention discloses a cable fault monitoring and early warning method and system, and relates to the technical field of fault monitoring. The method comprises the steps that cable operation state parameters and environment parameters are collected in real time through a distributed sensor array, and the cable operation state parameters comprise cable temperature, three-phase current, partial discharge signals, insulation resistance, grounding current and mechanical vibration amplitude; the environment parameters at least comprise temperature and humidity corresponding to a cable laying environment; preprocessing the cable operation state parameters and the environment parameters, and generating a standardized feature matrix based on preprocessed multi-source data; inputting the standardized feature matrix into a pre-trained fault prediction model for processing to obtain a fault type and a fault risk index corresponding to the current operation state of the cable; and triggering an early warning mechanism according to the fault type and the fault risk index, and outputting corresponding fault position information.

Electrical storage system with: an electrical storage device (10); a load (20); a line (PL) configured to connect the electrical storage device (10) and the load (20); a relay (SMR-G) that is provided in the line (PL); a capacitor (C11) which has one end connected to the electrical storage device (10) and the other end connected to a ground; a voltage sensor (21) configured to detect a voltage value of the capacitor (C11); a first insulation resistance (RB) which is set up between the electrical storage device (10) and the ground; a second insulation resistor (RL) which is installed between the load (20) and the ground; a first current path (L1) which includes the first insulation resistance (RB); a second current path (L2) comprising the conductor (PL) and the second insulation resistance (RL); and a control unit (50) that is configured to (a) Controlling ON and OFF of the relay (SMR-G), and (b) Determine that the relay (SMR-G) is blocked in an ON state if the voltage value is substantially equal to a second voltage value in a case where control to turn off the relay (SMR-G) is carried out, where a first resistance value is higher than a second resistance value, the second voltage value is higher than a first voltage value, the first resistance value is a resistance value of the first insulation resistance (RB), the second resistance value is a resistance value of the second insulation resistance (RL), the first voltage value is a voltage value when a discharge current of the electrical storage device (10) flows to the capacitor (C11) in the first current path (L1), the second voltage value is a voltage value when the discharge current of the electrical storage device (10) flows to the capacitor (C11) in the second current path (L2).

The invention relates to the technical field of whole vehicle fault detection, and particularly provides a whole vehicle insulation fault detection method and device, a medium and equipment, the method is applied to a controller in a whole vehicle high-voltage system, and the method comprises the steps that the current state of a whole vehicle is acquired; the current state comprises a static non-charging and non-high-voltage state and other states, and the other states comprise a static non-charging and high-voltage state, an alternating current charging state, a direct current charging state or a driving state; analyzing the insulation resistance value in the current state to determine the insulation fault type of the whole vehicle; wherein the insulation fault type comprises a battery hardware fault, an electric drive system fault, an air conditioning system fault, a heater system fault, a storage battery charging system fault, an assembly system fault or a charging pile fault. According to the embodiment of the invention, automatic and accurate detection and positioning of the vehicle insulation fault can be realized.

The invention discloses a wide-temperature-range insulation resistance testing device with an anti-freezing sealing structure, and relates to an anti-freezing sealing structure of insulation resistance testing equipment. The problem that an existing insulation resistance testing device is poor in sealing performance in an extremely cold environment is solved. The device comprises a main body and a heat preservation layer wrapping the outer wall of the main body. The device further comprises an anti-freezing sealing mechanism and a pressing mechanism. The anti-freezing sealing mechanism is arranged at the top of the main body and is used for sealing a control panel and a wiring terminal of the main body; and the pressing mechanism is arranged in the main body and is used for continuously applying pressing force to the anti-freezing sealing mechanism so as to counteract a sealing gap caused by shrinkage or hardening of the sealing element due to low temperature. The device has the beneficial effect that the sealing effect of the anti-freezing sealing cover on the control panel part and the wiring end part of the device is improved.

The invention discloses an insulation resistance measurement method, a measurement module and an anti-reverse power transmission isolation device, and relates to the field of operation and maintenance of distribution lines, and the key points of the technical scheme are as follows: a control voltage signal is generated according to the voltage demand of the insulation resistance of a test line sent by a user, and a PWM square wave signal with a duty ratio is generated according to the control voltage signal; performing high-frequency voltage transformation and voltage doubling rectification on the PWM square wave signal to obtain a direct-current voltage; calculating a current average value of the measurement loop when each resistance measurement gear is switched; presetting a current coefficient of each resistance measurement gear and weight coefficients of two adjacent resistance measurement gears; and when the current average value is greater than or equal to the product of the current coefficient and the weight coefficient, calculating the insulation resistance value of the measured circuit according to the current average value, the direct-current voltage and the resistance value corresponding to the resistance measurement gear.

The invention discloses a preparation method of a high-strength glass insulator, and belongs to the technical field of electrical equipment materials, and the preparation method comprises the following steps: S1, preparing a glass matrix material: mixing 65-75% by weight of SiO2, 10-25% by weight of Al2O3, 5-8% by weight of B2O3, 3-5% by weight of CaO, 1-3% by weight of Na2O and 1-2% by weight of MgO, and melting to form molten glass; and S2, gradient heat treatment: injecting the molten glass into a mold for molding, and sequentially carrying out treatment in three stages of annealing at the high temperature of 650-700 DEG C, slow cooling at the medium temperature of 400-450 DEG C and stabilizing at the low temperature of 200-250 DEG C. The compressive strength is greater than or equal to 500 MPa, and the insulation resistance is greater than or equal to 1000 G omega.cm.

The invention provides an insulation on-line monitoring system and method of a direct current power supply system, and solves the technical problem that the existing monitoring means is not suitable for the direct current power supply system. The system comprises a bridge type insulation detector used for timely detecting the insulation resistance value of the high-voltage DC bus and feeding back the insulation resistance value; the leakage current sensor is used for detecting the insulation resistance value of the high-voltage direct-current branch in real time and feeding back the insulation resistance value; and the injection type insulation detector is used for detecting the insulation resistance value of the low-voltage direct-current bus in real time and feeding back the insulation resistance value. An appropriate direct-current power supply system insulation on-line monitoring method is designed through analysis from the aspects of electrical architecture, voltage class, insulation abnormity rapid positioning and the like of the direct-current power supply system, the insulation problem is rapidly positioned, and a high-precision insulation monitoring scheme is achieved. Insulation abnormal conditions of various levels of electrical systems can be found in time, and the safety of personnel and electrical equipment is fully guaranteed.

The utility model relates to the field of insulation resistance detection tools, in particular to an insulation resistance detection tool for a hot-line work site, which is characterized in that a pull rod I and a pull rod II which are connected with each other are mounted in the middle of a handle piece in a limiting and sliding manner, one side of the pull rod I is connected with the pull rod, and a pair of clamping claws is rotationally mounted at one end of the pull rod II through an adapter plate. According to the utility model, the transverse rod is pulled to drive the clamping claw to move through the pull rod assembly, the clamping claw is in extrusion contact with the inner wall of the handle piece in the moving process and deflects inwards to clamp the test piece, and the clamping claw can stably clamp the test piece along with the movement of the transverse rod; and meanwhile, the wire penetrates through the pull rod assembly and is mounted on the rotating column of the clamping jaw for connection testing, so that the stability and the safety during detection are effectively ensured.

The application relates to the technical field of power grid planning, in particular to a power distribution network dynamic planning system based on digital twinning, which comprises an acquisition module, a simulation module, a first determination module, a determination module, a second determination module, an adjustment module, a correction module and an output module. The current, voltage, position offset, tilt angle and insulation resistance value of the equipment are collected in real time, the simulation analysis of the digital twinning model is combined, the fault equipment and the abnormal equipment can be accurately identified, the acquisition cycle and the coincidence rate threshold are dynamically adjusted, the monitoring efficiency and the accuracy are optimized, the power allocation planning report is generated, a scientific basis is provided for the optimized operation of the power distribution network, especially in emergency situations such as after an earthquake, power supply can be quickly responded and restored, the influence of disasters on the power grid is reduced, and the problems of inaccurate monitoring and inflexible planning caused by the complex influence of the earthquake and excessive dependence on static parameters are effectively solved.

The application discloses a kind of leakage detection methods of liquid cooling system, it is related to leakage detection technical field, including, in the backwater port of liquid cooling unit, pressure sensor is arranged, the pressure in backwater pipeline is monitored in real time;Water immersion sensor is laid out in the low-lying area of battery chamber and electrical chamber, is connected with DC24V power supply line by water immersion rope, for detecting liquid leakage state;Simultaneously, insulation detection module is configured, for measuring the insulation resistance of high-voltage busbar to ground in system.Through two-way detection mechanism, it is combined to judge that backwater pressure is lower than preset threshold value or water immersion sensor output alarm and insulation resistance anomaly, once judging that leakage fault occurs, system executes protection action including PCS emergency stop, direct current circuit breaker tripping and battery disconnecting;The application overcomes the problem of single monitoring means in the prior art, such as slow reaction, false negative or false positive, etc., realizes fault judgment and protection action at the initial stage of leakage, thereby improving the safety and reliability of liquid cooling system operation.

The invention discloses a state evaluation system of a metal oxide resistor disc for a lightning arrester, relates to the technical field of electrical performance testing, and solves the technical problems that the specific influence degree of environmental factors on insulation resistance is difficult to accurately quantify, and meanwhile, the influence of various factors such as environmental conditions and operation conditions on the performance of the resistor disc cannot be comprehensively considered. By establishing a correlation model, combining the insulation resistance with environmental parameters, fully considering the influence of environmental factors on the insulation performance of the resistor disc, and by establishing the correlation model, the change rule of the insulation resistance can be analyzed more accurately, and reasonable performance change caused by external conditions is considered, so that the insulation performance of the resistor disc is improved. And the performance degradation of the resistor disc can be reflected more objectively in the subsequent comparison with actual detection data. Aging factors are calculated for each region, and the comprehensive health index of the resistor disc in each region is analyzed in combination with the relative deterioration degree coefficient of the insulation resistor, the relative deterioration degree coefficient of the resistive current and the dielectric loss coefficient.

The application relates to the technical field of capacitors, and discloses a multilayer ceramic capacitor and a preparation method thereof. The multilayer ceramic capacitor comprises a ceramic body and two end electrodes arranged on two end surfaces of the ceramic body respectively, the end electrodes extend to the outer circumferential surface of the ceramic body, the ends of the two end electrodes are arranged oppositely and have a distance therebetween, an insulating layer is arranged on the end electrodes, a conductive layer is coated on the insulating layer, the conductive layer covers the insulating layer and extends to the end electrodes, and the end portions of the end electrodes are exposed to the conductive layer. The application can realize automatic electrical performance sorting, the connection area of the multilayer ceramic capacitor and the circuit board is small, the distance between the two welding points is small, the piezoelectric vibration of the multilayer ceramic capacitor is effectively inhibited from being transmitted to the circuit board, the ringing noise of the circuit board is reduced, the plating solution penetration path is long, the plating solution cannot reach the inner electrode, and the insulation resistance is not reduced.

This invention discloses an insulation monitoring method and system for cascaded battery energy storage systems. The monitoring method includes the following steps: constructing a signal acquisition module, with a switch and bias resistor connected in series between the positive and negative busbars and ground; acquiring the voltages of the positive busbar to ground and the negative busbar to ground of the battery clusters when the first and second switches are in different on / off states; calculating the insulation resistance values ​​of the positive and negative busbars to ground based on the voltages of the positive and negative busbars to ground, and sending them to a fault diagnosis module; judging the insulation performance of each battery cluster based on the insulation resistance values, and sending the data to a control and protection module; and controlling the corresponding battery cluster to take control and protection actions based on the insulation performance data. The monitoring method proposed in this invention has a simple structure and can detect double-point grounding faults, unaffected by the equal or similar decrease in the insulation resistance of the positive and negative busbars to ground.