222results about "Testing vessel construction" patented technology

The invention relates to an unmanned aerial vehicle zero-value insulator live detection device and method, an execution module comprises an AI image recognition unit and a detection probe, the detection probe integrates a voltage sensor and a resistance sensor and supports two modes of live resistance detection and distributed voltage detection, the AI image recognition unit is adjacent to the root of the detection probe, and the AI image recognition unit is adjacent to the root of the detection probe. The image acquisition module is used for acquiring insulator steel cap images and outputting positioning signals; the controller mainboard is electrically connected with the detection probe, the rotating mechanism and the AI image recognition unit through shielding cables, and the controller mainboard is used for receiving a positioning signal of the AI image recognition unit, receiving voltage detection data and / or current detection data transmitted by the detection probe, processing the detection data and obtaining a detection result of the state of the insulator. According to the invention, a dual-mode cooperation mechanism of'distributed voltage preliminary screening + charged resistance verification 'is adopted, and AI automatic positioning and mode automatic switching functions are combined, so that the detection efficiency is remarkably improved.

The invention discloses a withstand voltage test device and a withstand voltage test method for an insulating product, and relates to the technical field of withstand voltage tests. The insulation product voltage withstanding test device comprises a workbench, an insulation stand column, a transverse supporting rod, a conductive stand rod, a conductive pressing plate, a box body assembly and a separation support. And when the outer side wall of the heel of the tested insulating boot is pressed on the separation bracket, the steel ball can roll out through the skirt edge opening which is arranged obliquely downwards and falls into the inner cavity of the insulating boot to be tested, and the third conductive liquid at the bottom surface position of the tested insulating boot is adhered to the separation bracket and flows downwards along the separation bracket. The first conductive box body can conduct electricity when being crimped on the conductive pressing plate and is used for forming a loop required by a withstand voltage test of the insulating gloves; the second conductive box body can conduct electricity when being crimped on the conductive pressing plate, and is used for forming a loop required by a withstand voltage test of the insulating boot; and the two wires do not need to be assembled, disassembled and arranged when the two wires are replaced, so that the operation steps of a user are reduced.

The present disclosure provides an insulation detection apparatus and method, and an energy storage apparatus, and relates to the technical field of energy storage safety. The insulation detection apparatus includes: a coupling conductor and a signal acquisition unit, where the coupling conductor and the signal acquisition unit are electrically connected, the coupling conductor and the signal acquisition unit are used to form an insulation detection loop with a device under test, and the signal acquisition unit is further used to detect an electrical signal in the insulation detection loop. The coupling plate and signal acquisition unit used in the present disclosure have a simple structure and low cost. Compared with the existing insulation impedance detection, the present disclosure has a high detection sensitivity and more reliable detection result.

The invention discloses a terahertz reflectance spectrum-based insulating oil micro-water content and aging detection method, device and equipment and a storage medium, and relates to the technical field of dielectric spectroscopy, and the method comprises the following steps: sampling each standard sample to obtain a to-be-detected sample, placing each to-be-detected sample in a sample bearing vessel to obtain an oil film layer, reflecting terahertz wave beams are utilized to irradiate each oil film layer to obtain a terahertz amplitude spectrum and a terahertz phase spectrum, a target three-layer optical model is utilized to perform inversion to obtain a complex dielectric function frequency spectrum, and a preset sub-dielectric model is utilized to fit the complex dielectric function frequency spectrum to obtain a main resonance characteristic and a characteristic parameter set; determining a reference micro-water content based on the main resonance characteristics, determining training data based on the characteristic parameter set, and constructing a target multi-task regression model; and processing the characteristic parameter set by using the model to obtain an initial prediction result and a confidence interval, verifying the prediction result to obtain a target prediction result, and improving the efficiency of detecting the micro-water content and aging of the insulating oil.

The invention belongs to the technical field of electrical equipment insulation detection, and particularly relates to a cable insulation wide-temperature-range dielectric loss detection system which comprises a human-computer interaction interface, a main control processor, an acquisition card, a linear high-voltage amplifier, a micro-current preamplifier, a three-electrode test, a gear shifting communication control module, a power module and a signal conditioning module. The main control processor is connected with the power supply module and the acquisition card, the main control processor is connected with the temperature sensor through the signal conditioning module, the acquisition card is connected with the linear high-voltage amplifier and the micro-current pre-amplifier, and the micro-current pre-amplifier is connected with the gear shifting communication control module; the ultrathin thin film resistance type PT100 temperature sensor is combined with a wave-shaped groove isolation structure, so that the heat conduction error of adjacent temperature measurement nodes is effectively reduced. The depth of the wave-shaped groove is 1.5-3 times of the wire diameter of the thermocouple, and the groove is filled with a nanometer aerogel heat insulation material, thereby guaranteeing the independent measurement of a temperature field, and enabling the thermal interference among a plurality of measurement points to be reduced.

The invention discloses a portable lightning arrester performance detection device and a use method thereof, and relates to the field of lightning arrester detection. The portable lightning arrester performance detection device comprises a direct-current high-voltage generator and a box cover arranged on the direct-current high-voltage generator, a flat cable is arranged between the direct-current high-voltage generator and the box cover, two test main lines are embedded in the flat cable, a placement cavity is formed in the box cover, and the test main lines are arranged in the placement cavity. And a plurality of contact type power connection seats are arranged in the placement cavity in parallel based on the test main line, and each contact type power connection seat can be used for placing the lightning arrester main body and is electrically connected with the lightning arrester main body in a contact manner. According to the portable lightning arrester performance detection device, the multi-station parallel contact type power connection seat is arranged in the placement cavity of the box cover, the test branch line is connected with the test main line, a plurality of lightning arrester main bodies can be placed at the same time, a single detection loop is independently controlled through the change-over switch, and batch detection and station switching are achieved.

The invention provides a long-gap in-oil arc test platform and an energy calculation method, and relates to the technical field of in-oil arc energy calculation, the long-gap in-oil arc test platform comprises a current source loop and a discharge loop, the current source loop is used for providing large current for the discharge loop, and the discharge loop is used for providing large current for the discharge loop. The discharge loop comprises an in-oil arc test tank body, a voltage measuring instrument, a current measuring instrument, a temperature measuring instrument, an image acquisition instrument and N metal probes, wherein N is a positive integer. According to the energy calculation method, short arc injection energy and loss energy are calculated through piecewise linear discretization, and energy calculation errors are reduced; meanwhile, the arc energy space-time distribution characteristics are obtained, and a theoretical basis is provided for research of an arc dynamic breakdown mechanism.

A method for detecting a partial discharge in electric power equipment is disclosed. Two or more narrowband signals corresponding to respective frequency bands of the partial discharge are obtained by two or more receivers, and a temporal coincidence of the two or more narrowband signals is detected, thereby indicating a possible presence of the partial discharge. Then a synchronous recurrence of the partial discharge over a plurality of power cycles is determined, thereby validating the possible presence of the partial discharge. A corresponding system is also provided.

The utility model discloses a discharge model for simulating bubbles in transformer oil, which relates to the technical field of electrical test, and comprises an oil cylinder, a high-voltage electrode, a low-voltage electrode and a circulating mechanism, a sealing cavity is formed in the oil cylinder, insulating oil is contained in the sealing cavity, and a first through hole and a second through hole are respectively arranged on two opposite sides of the oil cylinder; the high-voltage electrode is located in the sealing cavity and led out of the oil cylinder through a high-voltage lead. The low-voltage electrode is located in the sealing cavity, is spaced from the high-voltage electrode and is led out of the oil cylinder through a low-voltage lead; the circulating mechanism comprises an oil pump and a circulating pipe, two ends of the circulating pipe are respectively communicated with the first through hole and the second through hole to form a circulating loop, the oil pump can pump the insulating oil to circularly flow along the circulating loop, the circulating pipe is communicated with an air source, and the air source can inject bubbles into the insulating oil through the circulating pipe. The discharge model provided by the utility model can more accurately simulate the discharge process of the bubbles under the flowing of the insulating oil, and improves the simulation degree of the test.

The invention relates to a C-GIS circuit breaker automatic partial discharge test system and a test method thereof, the automatic partial discharge test system comprises a test end device and a production line end device, the test end device comprises a shielding room, and a high voltage test device, an automatic commutation device, an automatic wiring device and an automatic opening and closing control device which are arranged in the shielding room; the production line end equipment comprises an automatic roller line, a visual system, a tool positioning module, an aviation plug automatic butt joint tool, a grounding probe butt joint tool and an automatic triggering circuit breaker opening and closing button tool. According to the automatic partial discharge test system, a circuit breaker is automatically conveyed into a shielding room through an automatic roller line, and according to circuit breaker information obtained by scanning a bar code through a visual system, circuit breaker positioning, automatic aviation plug and grounding probe automatic butt joint are achieved through the tool positioning module, the aviation plug automatic butt joint tool and the grounding probe butt joint tool respectively. The whole set of test process can be completed without personnel entering the laboratory, so that the overall test safety is improved.

A system and method of detecting leakage in a pouch-type battery cell includes a press unit configured to position and press the pouch-type battery cell, and a measurement unit configured to measure the insulation resistance of the cell pressed by the press unit.

This utility model provides a transformer partial discharge testing device, mainly relating to the field of transformer technology. The device includes a housing and metal electrodes. The metal electrodes are slidably disposed on the top of the housing. A rectangular cylinder is fixedly disposed on the top of the housing. A support frame is slidably disposed inside the rectangular cylinder. A limiting block is hinged to the outside of the rectangular cylinder, and the limiting block abuts against the side of the support frame. An L-shaped fixing plate is fixedly disposed on the outside of the rectangular cylinder, and a DC solenoid valve is fixedly disposed on the L-shaped fixing plate. The end of the DC solenoid valve abuts against the limiting block. The advantages of this utility model are: after the test is completed or the monitoring system detects an abnormality, the metal electrodes can be quickly and safely separated from the transformer, effectively avoiding the risk of electric shock due to residual charge and greatly ensuring the safety of operators.

The utility model relates to the technical field of insulation protection appliance detection, in particular to a full-automatic water injection insulation glove test device, which comprises a bin body, a clamping mechanism is fixedly mounted in the middle of the upper end surface of the bin body, and a water injection mechanism is fixedly mounted on the upper end surface of the bin body behind the clamping mechanism; the bin body comprises a water tank, and the outer side of the water tank is coated with an insulating sleeve; the clamping mechanism comprises a top groove, a first controller is fixedly installed in the top groove, storage battery clamps are installed at the bottom of the first controller at equal intervals, and air cylinders are fixedly installed on the two sides of the bottom of the water tank correspondingly; the water injection mechanism comprises a top plate, a second controller is fixedly installed on the upper end face of the top plate, a water injection pipe penetrates through the second controller, and the bottom of the water injection pipe is located at the rear end of the storage battery clamp below the water tank. The utility model solves the problems that water is difficult to pass through small gaps on the glove and the detection result is not accurate due to different pressures inside and outside the glove.

The invention discloses a frequency converter anti-breakdown capability testing device, and belongs to the technical field of frequency converter testing devices. Comprising a rack, and a fixing frame is fixedly installed on the rack; the material table is rotationally mounted on the rack, and a placing groove for placing the frequency converter is formed in the material table; the testing arm is installed on the fixing frame in a lifting mode and provides rotation of the material table to enable the containing groove to be located on the lower side of the testing arm; the monitoring block is fixedly mounted on the testing arm, and an electrode column is arranged on the monitoring block; a fixed cylinder is fixedly installed on the monitoring block, and the upper end of the electrode column is slidably arranged in the fixed cylinder. The frequency converter anti-breakdown capability testing device provided by the invention has the beneficial effects that through the arrangement of the electrode column and the fixed cylinder, the lower end of the electrode column is in contact with the power connection terminal and slides in the fixed cylinder, so that gas in the fixed cylinder is discharged into the connecting cylinder, and the connecting spring is compressed; at the moment, pre-tightening force exists between the lower end of the electrode column and the power connection terminal.

The invention discloses an insulator impact breakdown voltage measurement system and method, and belongs to the field of electrical measurement. The system comprises an upper computer, a plurality of cameras, a high-voltage power supply and an insulator testing device, the insulator testing device comprises a closed cavity, a disc platform used for placing a plurality of insulators to be tested, a high-voltage electrode and an ionic wind module. The upper computer is used for controlling the ion wind module according to preset ion current parameters after the closed cavity is filled with the insulating gas, so that the ion wind module releases positive and negative ion current; the upper computer is also used for controlling the high-voltage power supply to supply power to the high-voltage electrode which forms a measuring loop with each insulator to be measured, so that the high-voltage electrode applies impact breakdown voltage to each insulator to be measured; and the upper computer is also used for obtaining an impact breakdown voltage measurement result of the insulator to be tested according to the number of the discharge channels corresponding to the discharge images of the cameras around the insulator testing device. According to the invention, the efficiency and accuracy of insulator impact breakdown voltage measurement are improved.

The invention belongs to the technical field of anti-lightning performance evaluation, and particularly relates to a method for evaluating the anti-lightning performance of large equipment, which comprises the following steps of: designing, processing and manufacturing a scaling part for the to-be-evaluated large equipment, and establishing equivalent mapping between the scaling part and an ideal rod-plate reference configuration; constructing a test environment; fixing the scaled part according to a service typical attitude, setting an equivalent gap between the scaled part and the counter electrode based on equivalent mapping, and dividing an attachment evaluation area number; setting impulse voltage, and configuring a measuring system: respectively carrying out lightning impulse tests in three types of environments; calculating evaluation indexes based on the test result, wherein the evaluation indexes comprise a first compression resistance coefficient and a second compression resistance coefficient; and based on the calculated evaluation indexes, obtaining a comprehensive evaluation value, and forming an evaluation conclusion. According to the invention, the problem of the real-size lightning stroke test of large equipment is solved, a unified, comparable and traceable lightning stroke resistance evaluation system is established, and a basis can be provided for structure optimization and protection design.

The invention discloses an electrode device and method for measuring space charges through pressure-electric field-temperature coupling, and the device comprises an upper electrode structure which comprises an upper connecting plate, a conductive bolt, cylindrical ceramic, and an upper electrode terminal; the bottom of the conductive bolt is fixedly connected with the upper connecting plate, and the top of the conductive bolt is provided with radial scales and can be in contact with a fixed surface of an external calibration platform through thread feeding; the lower electrode structure comprises a lower connecting plate, plate-shaped ceramic and a lower electrode terminal; the lower electrode terminal comprises a heating resistance wire; two ends of the high-voltage pulse unit are respectively connected to the upper and lower electrode terminals; the signal collecting and converting unit is connected with the lower electrode terminal; a to-be-tested sample is clamped between the cylindrical ceramic and the plate-shaped ceramic; the upper and lower connecting plates apply stress to a to-be-tested sample through engagement of connecting bolts; and a pressure sensor is arranged between each connecting bolt and the upper connecting plate. The device has the functions of pressure regulation and control and real-time measurement of the thickness of the sample, and can more accurately measure the space charge in the insulating material of the cable accessory.

The present invention discloses a high-voltage cable test system and a method for building the same. The high-voltage cable test system includes: a high-voltage cable test auxiliary device, which includes an insulating gas tank and an intermediate GIS terminal. The insulating gas tank has a chamber for filling insulating gas, a first interface at one end of the chamber, and a second interface at the other end of the chamber. The first interface is for the on-site GIS terminal connected to the high-voltage cable to pass through. The intermediate GIS terminal passes through the second interface, and the intermediate GIS terminal is electrically connected to the on-site GIS terminal through a conductor arranged in the chamber; an intermediate cable, one end of which is connected to the intermediate GIS terminal; an outdoor terminal, which is connected to the other end of the intermediate cable; and a test device, which is connected to the outdoor terminal through a high-voltage wire. When the safety clearance of the space where the GIS switch is located is insufficient and the space is limited and inconvenient to place the test device, the high-voltage cable can still be tested.

The invention discloses a device for avoiding electrode air discharge in DBC lining plate insulation characteristic detection. The device comprises a quartz glass cavity, a PPA insulation top cover, an electrode column, a copper bottom plate and a PEEK fixing bolt. The quartz glass cavity comprises a cavity main body and observation windows, the cavity main body is of a hollow shell structure, and the observation windows are holes formed in the four side walls of the cavity; the PPA insulating top cover is provided with an insulating baffle and an electrode column mounting hole, so that the testing cavity can test a plurality of DBC lining plates at multiple intervals, air discharge among the electrode columns is avoided, one end of each electrode column extends into the cavity main body, the other end of each electrode column is provided with a thread, and the electrode columns can penetrate through the electrode column mounting holes to be locked and fixed. The vertical distance between the bottom of the electrode column and the copper bottom plate can be adjusted by rotating the electrode column outside, so that DBC lining plates with different thicknesses can be tested; the four PEEK fixing bolts respectively penetrate through the PEEK fixing bolt mounting holes in the top corners of the PPA insulating top cover and are tightly connected with the PEEK fixing bolt mounting holes in the copper bottom plate, so that the quartz glass cavity is tightly fixed by the PPA insulating top cover and the copper bottom plate, and the device is widely applied to the fields of high-pressure and high-temperature insulation characteristic detection of various DBC lining plates and the like.

The invention discloses a long-time breakdown test method and system for a cable insulation sample wafer, and the method comprises the steps: introducing an AC / DC power supply output end into a high-voltage isolation oven through a high-voltage bushing, and connecting the AC / DC power supply output end with a test multi-electrode; respectively dividing the plurality of test samples into a plurality of areas, increasing test voltage of the test multi-electrode based on a preset step length, respectively carrying out a breakdown test on the first areas of the plurality of test samples, and recording breakdown voltages of different test samples; processing the plurality of breakdown voltages of the different test samples, and determining first insulation breakdown voltages of the different test samples; carrying out a breakdown test on a plurality of areas except the first area of the plurality of test samples based on different proportions of the first insulation breakdown voltage by testing the plurality of electrodes, and recording the breakdown time when the breakdown voltage occurs in the plurality of areas of the plurality of test samples in different proportions; and processing the breakdown time, and determining insulation breakdown time of different proportions of the first insulation breakdown voltage based on parameters obtained after processing.

The invention discloses a curvature electrode performance testing device and method for cable slicing, and belongs to the technical field of high-voltage electrical equipment tests.The device comprises a curvature electrode device and a multi-environment simulation cavity, and the curvature electrode device is arranged in the multi-environment simulation cavity; the curvature electrode device comprises a height adjusting screw knob, a high-voltage curvature electrode, a grounding curvature electrode, a temperature control heating device and a supporting frame body; a to-be-tested cable slice is placed between the high-voltage curvature electrode and the grounding curvature electrode for performance test; a height adjusting screw knob is arranged above the high-voltage curvature electrode to adjust the distance between the electrodes, and a temperature control heating device is connected with the grounding curvature electrode to heat the cable slice; the multi-environment simulation cavity is connected with an external high-voltage power supply and provides a simulation test environment. The problems that an existing testing device is poor in attachment and adjustability and lacks multi-physical field coupling and environment simulation capacity can be solved, and the experimental accuracy and reliability of cable slices under complex working conditions are improved.

The invention discloses a device and method for testing the voltage breakdown performance of a cable in a high-temperature environment, and belongs to the technical field of electrical insulation, the device comprises an insulation bin, the two sides of the insulation bin are fixedly connected with an access bin and an outlet bin respectively, connecting holes are formed in the connecting positions of the access bin and the insulation bin and the connecting positions of the outlet bin and the insulation bin, and the connecting holes are communicated with the insulation bin. An insulating base is arranged at the bottom in the insulating bin, two grooves are formed in the upper surface of the insulating base, a supporting bracket is clamped in each groove, the upper parts of the supporting brackets are in contact with a cable to be tested, a conductive mechanism is arranged on the front side of the insulating base, and the conductive mechanism is connected with the insulating base. According to the test equipment, the voltage breakdown phenomenon of the cable under the real use condition can be simulated, the obtained test data is closer to the real use condition, and the electrical strength performance of the cable insulation material can be better evaluated.

Occurrence of partial discharge is reduce and the test of electrical properties of a semiconductor device is and stably performed. A semiconductor testing apparatus includes a stage, a probe, a separation section, and a gas supply section. The probe performs electrical input and output to and from the semiconductor device held on the stage. The separation section separates the space above the semiconductor device held on the stage into the pressurized space and the probe space including the probe. The gas supply section supplies gas to the pressurized space to pressurize the pressurized space.

The disclosure relates to a test device (22) for evaluating an electric arcing property of a traction battery (12) of a vehicle. The test device (22) comprises an electrically nonconductive or electrically insulated holder (30), a first electrode, and a second electrode. The first electrode has a first end and a second end. The second electrode has a first end and a second end. The first electrode and the second electrode are supported on the holder (30) such that the first ends form a gap between each other. Additionally, a test system (14) for evaluating an electric arcing property of a traction battery (12) of a vehicle is described. The test system (14) comprises such a test device (22), an electric source (24), and an electric monitoring unit (26). Furthermore, a use of a test device (22) and / or a use of a test system (14) are shown. Additionally, a method for evaluating an electric arcing property of a traction battery (12) of a vehicle is presented.

The invention relates to a soil spark discharge critical breakdown field intensity measuring device, system and method, a soil test cylinder encloses a rotating cavity, to-be-measured soil is placed in the rotating cavity, a first metal circular plate electrode covers the top of the to-be-measured soil, and a second metal circular plate electrode is located at the bottom of the rotating cavity; the first metal circular plate electrode can move relative to the soil test cylinder; the measuring device and the impulse current generator form a closed loop, the voltage divider and the current transformer are both arranged on the closed loop, and the voltage divider and the current transformer are both connected with the data collector; the measuring method comprises the following steps: adding to-be-measured soil, connecting the measuring system, applying impact current, and calculating critical breakdown field strength. A uniform electric field environment is constructed in the soil by utilizing the symmetry of the soil test cylinder, so that the fringe effect and the end effect can be effectively avoided, the relatively accurate soil spark discharge critical breakdown field strength can be obtained, and a basis is provided for the impact characteristic simulation calculation of the grounding device.

This disclosure relates to the field of insulating material testing, including a method and system for evaluating the nonlinear strength of insulating materials based on high-frequency component analysis. The method involves applying an excitation electrical signal of a first preset frequency to the insulating material under test; acquiring the response signal obtained by the insulating material in response to the excitation electrical signal based on a second preset frequency; performing time-frequency transformation on the response signal to obtain the frequency characteristics of various preset higher harmonic components; and determining the evaluation result of the nonlinear strength of the insulating material based on the frequency characteristics of these higher harmonic components. This method allows for obtaining the evaluation result of the nonlinear strength with a single excitation and response acquisition; it eliminates the need for multi-voltage point step testing in traditional techniques, shortening the testing cycle, improving testing efficiency, and enabling efficient, accurate, and standardized determination of the nonlinear strength evaluation result.

The utility model provides a high-voltage switch cabinet discharge gas diffusion simulation device, which relates to the technical field of gas diffusion simulation, and comprises a box body, a simulation cabin is arranged in the box body close to the bottom, a gas environment detection equipment main body is arranged in the box body close to the top end, and a gas environment detection equipment main body is arranged in the box body close to the left side. A built-in groove is formed in the bottom of the simulation bin, a discharging pipeline communicated with the built-in groove is arranged at the bottom of the left side of the box body, and an opening and closing assembly is installed in the built-in groove to control the gas release rate. Through the air pressure sensor and the temperature sensor, the temperature and gas pressure change in the simulation bin in the simulation process can be monitored, the point discharge model, the suspension discharge model and the air gap discharge model are used in cooperation, collection of simulation data can be expanded, the gas diffusion simulation precision is greatly improved, and the simulation efficiency is improved. And certain help is provided for insulation defect diagnosis and structure optimization of the high-voltage switch cabinet.

A method for fabricating a test sample of a rod-shaped composite insulator, the fabrication method comprising the following steps: Step 1: After excluding the end fittings of the rod-shaped composite insulator, perform segmented cutting along the direction perpendicular to the axis of the core rod and number them; Step 2: Pretreat the composite insulator segments; Step 3: Clamp both ends of the pretreated composite insulator segments with two metal electrodes, and then use two insulating clamping plates to clamp the upper metal electrode and the lower metal electrode, thereby fabricating an insulation test sample of the composite insulator. The insulation sample sampling of the composite insulator of the present invention can be standardized, avoiding the randomness and arbitrariness of sample sampling. For composite insulators of the same model, the same segmentation and sampling are adopted, and the test results are easy to compare; the lower metal electrode adopts a three-electrode structure, which can make the measurement of the insulation leakage current more accurate and scientific when performing insulation leakage current tests.

A sensor device for monitoring dielectric strength of a dielectric fluid has a sensor body which supports a sensitive part (SGi), designed for contact with the dielectric fluid. The sensitive part (SGi) comprises at least one pair of electrodes (E1, E2) having respective surface portions arranged at a predefined micrometric or sub-micrometric distance, to define therebetween at least one detection gap between which part of the dielectric fluid is suitable to seep in. The sensor device has a circuit arrangement comprising: —means for generating an electric field between the two electrodes of the at least one pair of electrodes (E1, E2) starting from a known supply voltage, and—means (V) for measuring a voltage representative of possible occurrence of an electric discharge between the two electrodes of the at least one pair of electrodes (E1, E2) through the dielectric fluid (5) present in the at least one detection gap (G), following generation of the electric field.

The invention relates to the technical field of insulation testing of high-voltage variable frequency motors, in particular to a testing structure and method for insulation breakdown or partial discharge of a variable frequency motor, and the structure comprises a hollow metal tube body which is wrapped by an insulating layer for insulation breakdown test or partial discharge test. A coaxial cylinder electrode structure for generating a radial uniform electric field is arranged in the middle of the metal tube body; the insulating layer is positioned on the surface of the coaxial cylinder electrode structure; a winding wire layer is arranged on the outer side of the coaxial cylinder electrode structure, the inner side of the winding wire layer makes contact with the coaxial cylinder electrode structure, and one end of the winding wire layer is led out to serve as an electrode to be connected with an external testing circuit. The two ends of the metal tube body serve as electrodes to be connected with an external test circuit. According to the invention, the electrical stress borne by insulation under the actual operation condition can be effectively simulated, and the comprehensive measurement of the insulation breakdown strength and the partial discharge characteristic can be realized. The structure is reasonable in design and convenient to manufacture, and has good repeatability and adaptability.