1150 results about "Varistor" patented technology

The invention discloses an electric energy metering box fault prediction method and system based on big data analysis, relates to the technical field of smart power grids, and solves the problems of progressive aging missing detection and instantaneous interference misjudgment caused by dependence on single parameter threshold alarm and fault positioning misalignment caused by multi-source data isolated analysis in the prior art. According to the scheme, electrical, environment and equipment state parameters are collected in real time through a multi-dimensional sensing network; the error drift of the mutual inductor is dynamically predicted based on an LSTM-Kalman filtering model, and core breakdown early warning is realized in combination with wavelet transform; outputting a corrected resistance value and a fault mark by using a BP neural network; predicting the life of the piezoresistor by adopting a gradient boosting decision tree and fusing lightning overvoltage characteristics; the transient interference is suppressed through the combination of a Transform self-attention mechanism and dynamic time warping; according to the method, the aging detection precision and the complex environment adaptability are remarkably improved, the misjudgment rate is reduced, and the multi-fault associated positioning and active defense capability is realized.

The invention relates to a power equipment self-repairing surge protection system based on artificial intelligence, and the system is characterized in that a surge detection module is connected between a live wire and a protection ground wire of power equipment, collects voltage and current data, and transmits the data to an artificial intelligence analysis unit; and the artificial intelligence analysis unit extracts the surge characteristic parameters, generates protection strategy parameters through a deep neural network, and controls the trigger thresholds of all levels of protection devices in the programmable protection circuit. The programmable protection circuit comprises a gas discharge tube capable of adjusting trigger voltage, a metal oxide varistor and a transient voltage suppressor diode, and is used for discharging surges with different energies step by step. The resettable fuse cuts off the circuit when the temperature exceeds a threshold value and recovers conduction after the temperature is reduced. And the controller receives and applies the protection strategy parameter output by the artificial intelligence analysis unit, and dynamically adjusts the trigger threshold value of the protection device, so that the response and protection performance of the system to the surge is improved, and the self-repairing and stable operation of the power equipment are realized.

The invention belongs to the technical field of film tensile testing devices, and particularly relates to a plastic film tensile testing device, which comprises a detection bottom plate, the upper end of the detection bottom plate is slidably connected with two moving plates along the horizontal direction; the stretching mechanism is arranged at the upper end of the detection bottom plate and is used for driving the two moving plates to move oppositely; and the two clamping mechanisms are symmetrically arranged on the opposite sides of the two moving plates and used for clamping and fixing the plastic film, and each clamping mechanism comprises a fixing block fixedly connected to the side wall of the corresponding moving plate. By arranging the length adjusting mechanism, in the clamping process, for plastic films with different thicknesses, the downward sliding distances of the pressing block are different, so that the pressure borne by the piezoresistor below the pressing block is different, the stretching parameters of the piezoresistor can be adaptively adjusted according to the thicknesses of the films, and the clamping efficiency is improved. And the detected tensile strength of the plastic film is more consistent with the actual performance.

The invention relates to the technical field of electrical fault detection, in particular to a voltage-sensitive device damage diagnosis system combined with pulse test, which comprises the following modules: an original signal acquisition module for inputting pulse sequences to a voltage-sensitive device, respectively recording voltage response signals and current response signals under each pulse sequence, and generating a response signal set; and performing wavelet decomposition on the voltage response signal and the current response signal based on the response signal set. According to the method, the pulse sequences are input, and the voltage response signals and the current response signals under the pulse sequences are recorded, so that data acquisition covers different working states, and feature missing possibly caused by a single test point is reduced. A wavelet decomposition mode is adopted, a voltage response signal and a current response signal are divided into different frequency intervals, separation of high-frequency and low-frequency characteristics is facilitated, local abnormal signals are not covered by global characteristics, and the capability of analyzing short-time fault characteristics is enhanced.

The present invention relates to the technical field of varistors, and specifically to a multi-layer chip varistor, comprising a protective shell, a cover plate being detachably mounted on the top of the protective shell, a resistor body being mounted in the protective shell; the resistor body being a multi-layer chip varistor; a first slide, the slide being arranged below the longitudinal sides of the protective shell, a longitudinal positioning plate for longitudinally positioning the resistor body being arranged above the slide; transverse positioning plates being respectively arranged on the transverse sides of the protective shell, the transverse positioning plates positioning the resistor body transversely in the protective shell, and the resistor body being limited in multiple directions through the structure of a top plate, a longitudinal positioning plate, a transverse positioning plate and a stop block, even if the rubber pad is aged and deformed due to the increase in the use time, the resistor body can still be effectively limited in the protective shell to prevent the resistor body from moving in the protective shell and affecting the normal use of the resistor body.

The utility model discloses a lightning protection device which comprises a surge protector body and a backup protector detachably arranged in the surge protector body, the backup protector comprises a tripping sliding block, a spring, a piezoresistor and a bimetallic strip, the bimetallic strip is fixedly connected with the tripping sliding block and abuts against a leading-out pin of the piezoresistor, and the tripping sliding block is connected with the spring. The trigger is used for triggering the tripping slide block to move; the spring abuts against the inner wall of the backup protector and the tripping sliding block, acts on the tripping sliding block and is used for opening the surge protector body. According to the utility model, the motion speed of the tripping slide block is accelerated through the cooperation of the bimetallic strip with the spring after the bimetallic strip is heated to expand and deform, so that the moving plate and the conductive protection block are electrically connected and separated, and the normal use of the tripping slide block, the spring and the bimetallic strip is prevented from being influenced by the explosion of the piezoresistor through the partition plate, thereby ensuring the timely breaking of the surge protector body and ensuring the safety of a circuit. And the product has the advantages of high sensitivity, small overall size, high safety and the like.

The invention provides an optimization method and an optimization device for electrical performance of a ZnO piezoresistor based on O2 heat treatment. According to the method, O2 is introduced into the ZnO varistor under the condition of heat treatment, and oxygen vacancies in the ZnO varistor are reduced under the oxygen atmosphere, so that the donor concentration is reduced, the carrier concentration is reduced, and the electrical performance of the ZnO varistor is remarkably improved. Besides, the optimization device provided by the invention is used for the heat treatment step in the electrical performance improvement process of the ZnO varistor, and the front and back surfaces of the ZnO varistor can be in full contact with gas in the heat treatment process, so that the electrical performance is uniformly and effectively improved.

A variable frequency drive with natural heat dissipation, comprising a housing and a front cover, wherein a mounting pad is fixedly mounted in the housing, and a varistor, a rectifier module, a filter, and an inverter module are mounted in sequence on the mounting pad; an air intake cavity is provided in the mounting pad; exhaust holes are provided between the air intake cavity and the top of the mounting pad; air inducing cavities are provided inside both sides of the housing; a through groove is provided between the air intake cavity and each air inducing cavity; and an air inlet is provided between each air inducing cavity and the outer wall of the housing. Natural heat dissipation is achieved within the variable frequency drive through multiple aspects, such as optimizing the design of an air duct, enhancing the heat conduction effect and heat conduction efficiency, and improving the internal environment. By means of a local heat-absorbing assembly, when localized overheating occurs within the variable frequency drive, heat generated by an automatic local component can be rapidly absorbed, thereby providing effective protection for the internal structure.

The utility model discloses a lightning stroke protection circuit of an electromagnetic heating device, which comprises an over-current, over-voltage and interference suppression circuit, a rectification filter circuit and a resonance heating circuit which are connected in sequence, the over-current, over-voltage and interference suppression circuit comprises a fuse FS01, a piezoresistor RZ01, a piezoresistor RZ02, a filter capacitor CX01 and a filter inductor L1, wherein the AC-L of the alternating current is sequentially connected with the fuse FS01 and the piezoresistor RZ01 in series to return to the AC-N, the AC-L of the alternating current is connected with the filter inductor L01 and the piezoresistor RZ02 in series to return to the AC-N, and the filter capacitor CX01 is connected with the piezoresistor RZ02 in parallel; the resonance heating circuit comprises a wire coil, a resonance capacitor CXZ30, an IGBT 30 and a TVS tube group. According to the utility model, two groups of piezoresistors are adopted in the overcurrent, overvoltage and interference suppression circuit, and a filter inductor is arranged in front, so that the protection response speed is improved, the effects of reducing voltage and clamping high voltage are achieved, the lightning stroke protection on a bridge rectifier is improved, and the IGBT of the resonance heating circuit is connected in parallel with a TVS tube group, so that the lightning stroke protection on the IGBT is improved, and the service life of the resonance heating circuit is prolonged. Therefore, the overall lightning protection of the electromagnetic heating device is improved.

A multilayer varistor has a stack structure including a plurality of layers stacked in a third direction. The multilayer varistor includes a first internal electrode electrically connected to a first external electrode, a second internal electrode electrically connected to the second external electrode, and a third internal electrode electrically connected to the third external electrode. The first internal electrode is disposed between the second internal electrode and the third internal electrode in the third direction.

The invention relates to the field of voltage dependent resistor welding equipment, in particular to a voltage dependent resistor welding device which is characterized in that a triangular block, a pushing block, a driving assembly and a lifting assembly are matched with one another, in the fixing and butt joint process of the voltage dependent resistor, the voltage dependent resistor is extruded, and pins of the voltage dependent resistor are expanded, supported and bent through the triangular block; and the pins of the piezoresistor are aligned with the jacks on the circuit board, so that the piezoresistor and the circuit board can be quickly butted, and the welding efficiency of the piezoresistor is improved. According to the invention, the triangular block, the pushing block, the driving assembly and the lifting assembly cooperate with each other, and the piezoresistor is extruded in the process of fixing and butting the piezoresistor, so that the triangular block expands and bends the pins of the piezoresistor, and the pins of the piezoresistor are aligned with the jacks in the circuit board; rapid butt joint of the piezoresistor and the circuit board is facilitated, and the welding efficiency of the piezoresistor is improved.

The invention discloses a piezoresistor assembling device, and belongs to the technical field of electronic component manufacturing equipment. The problems that existing piezoresistor assembly mostly depends on manual or semi-automatic equipment, production efficiency is low, consistency is poor, all mechanisms are lack of effective cooperation and need manual intervention, resistor insertion deflection is prone to occurring, sand filling is uneven, and cover plate correction precision is low are solved. The device comprises a shell feeding mechanism, a resistor feeding mechanism, a cover plate feeding mechanism, a material inserting mechanism, a sand filling mechanism, a cover plate assembling mechanism, a driving mechanism, a supporting mechanism and a control system. The supporting mechanism supports all the mechanisms, the driving mechanism drives the shell to move at the stations of the material inserting mechanism, the sand filling mechanism and the cover plate assembling mechanism, the control system coordinates all the mechanisms to act, and all the mechanisms sequentially complete feeding of the shell, the resistor and the cover plate, insertion of the resistor into the shell, sand filling and cover plate assembling. The device is mainly used for automatically completing full-process assembly of the piezoresistor, continuous automatic production is achieved, and the assembly efficiency and the product consistency are improved.

The invention discloses a piezoresistive pressure sensor chip and a preparation method thereof, and belongs to the technical field of micro-electromechanical systems. The piezoresistive pressure sensor chip comprises a substrate, the back of the substrate is etched with a cavity, the center of the cavity is provided with a cross-shaped mass block, and four hollow islands and four peninsula are arranged along the linear direction of the cross-shaped mass block; a plurality of groups of piezoresistor strips are arranged on the front surface of the substrate, each group of piezoresistor strips comprises a first piezoresistor strip component arranged close to the center and a second piezoresistor strip component arranged close to the side wall of the cavity, and the first piezoresistor strip component forms an internal Wheatstone bridge through a first metal lead group; the second piezoresistor strip component forms an external Wheatstone bridge through a second metal lead group; the glass is arranged on the substrate back. The piezoresistive pressure sensor chip can measure the pressure of a micro-pressure section, can bear high overload equivalent to a plurality of times of the full scale, and has the advantages of high sensitivity, good linearity, high precision, good dynamic performance and the like.

A sintered body has a first end face and a second end face opposite to each other in a first direction and a first side face and a second side face opposite to each other in a second direction. A first end face electrode is disposed on the first end face except for end portions of the first end face in the second direction. A second end face electrode is disposed on the second end face except for end portions of the second end face in the second direction. A first side face electrode is disposed on the first side face except for end portions of the first side face in the first direction. A second side face electrode is disposed on the second side face except for end portions of the second side face in the first direction.

The invention discloses an overhead ground wire magnetic induction energy taking device based on capacitance compensation, which is used for taking electricity of overhead line on-line monitoring equipment, an overhead line comprises a common ground wire and an OPGW ground wire, and the wiring mode of the overhead line is that the common ground wire is subjected to sectional insulation and single-point grounding, and the OPGW ground wire is grounded tower by tower; the energy taking device takes electricity from a parallel gap of a ground wire insulator and comprises a decoupling inductor, a piezoresistor and a rectifying and voltage stabilizing module, and the decoupling inductor and the piezoresistor are connected in series to form an overvoltage protection module and are connected in parallel with the parallel gap; the circuit also comprises a compensation capacitor, the compensation capacitor is connected in series with the rectification voltage stabilization module and then is connected in parallel with the piezoresistor, and the compensation capacitor is used for improving the theoretical maximum power of energy taking. The compensation capacitor is introduced into the ground wire energy-taking device to reduce or even eliminate the influence of inductance on energy-taking power, so that the energy-taking power is improved.

The invention relates to the technical field of manipulators, and discloses a three-dimensional force sensing mechanical finger which comprises a mechanical finger body and is characterized by further comprising a sensing module flexibly packaged in a fingertip of the mechanical finger body. The sensing module sequentially comprises a flexible printed circuit board, a force sensitive chip, a packaging shell and an elastic force transmission layer from the interior to the surface of the fingertip of the mechanical finger body. A center hole is formed in the force sensitive chip, and a plurality of piezoresistors are circumferentially and uniformly arranged on one side, far away from the flexible printed circuit board, of the force sensitive chip; the resistance values of the piezoresistors correspondingly change along with the change of the pressure borne by the mechanical finger body, so that the load size is obtained based on the initial resistance values and the resistance value change values of the multiple piezoresistors, and the sliding direction of the object is obtained based on the occurrence time of the sudden change of the resistance values of the multiple piezoresistors. Accurate quantification and sliding identification of fingertip pressure are achieved, the accuracy and sensitivity of man-machine interaction are improved, and the safety of the grabbing action of the mechanical arm is guaranteed.

The invention relates to the technical field of lightning protection circuit detection, in particular to a method and device for detecting the service life of a gas discharge tube, and the method comprises the steps: repeatedly calculating a plurality of performance loss characterization coefficients corresponding to each working condition time node of the gas discharge tube in a preset operation duration, and constructing a change curve of the fitting values of the performance loss characterization coefficients, determining a characteristic working condition time period according to the dispersion of the fitting value of the performance loss characterization coefficient of the plurality of working condition time nodes in each change curve section; and whether the performance of the gas discharge tube is abnormal or not is judged according to the change condition of the dispersion of the performance loss characterization coefficient fitting value in the characteristic working condition time period before and after the piezoresistor is switched on. Personalized sample data are established according to the environmental factor influence of the gas discharge tube and the change of the working condition of the circuit where the gas discharge tube is located, and scenarized operation state analysis is performed, so that the accuracy of performance life detection of the gas discharge tube is improved.

The invention discloses a linear beam double-island structure high-pressure pressure sensor chip with stress holes and a preparation method. The linear beam double-island structure high-pressure pressure sensor chip comprises a supporting layer, an insulating layer and a device layer which are arranged from bottom to top, a cavity is etched on the back of the supporting layer, a sensitive film is arranged right above the cavity, and a linear beam double-island structure is arranged on the sensitive film; the edge and the center of the straight beam double-island structure are respectively provided with four piezoresistor strips, the four piezoresistor strips are connected into a semi-open-loop Wheatstone bridge through five P-type heavily-doped silicon leads, five metal point electrodes are arranged at the center of the five P-type heavily-doped silicon lead areas, sealing rings are arranged on the outer sides of the peripheries of the five metal point electrodes, and the metal point electrodes are connected with the metal point electrodes through the P-type heavily-doped silicon leads. The adjacent P-type heavily-doped silicon leads and the sealing rings are separated by fine slits; according to the invention, the pressure bearing limit is effectively improved, the high range is ensured, excellent sensitivity and linearity performance are realized, the high pressure measuring capability of dozens of to hundreds of MPa is realized, the tolerable temperature is up to 400 DEG C, and the sensor is widely applied to the fields of petroleum, natural gas, chemical engineering, high-pressure equipment monitoring and the like.

The invention belongs to the field of MEMS sensors, and discloses a high-temperature-resistant MEMS pressure sensor chip and a packaging structure thereof. The chip is provided with an SOI substrate, an AlN layer and a SiO2 layer from bottom to top, a plurality of P-type piezoresistors are arranged on the uppermost layer of the SOI substrate and are symmetrically distributed at the stress concentration position of the edge of the elastic diaphragm; a channel which continuously penetrates through the AlN layer and the SiO2 layer is arranged above the P-type piezoresistor; a metal Pad is arranged in the channel; the upper end of the metal Pad is located on the uppermost layer of the high-temperature-resistant MEMS pressure sensor chip, and the lower end of the metal Pad is in contact with the P-type piezoresistor. According to the invention, the relatively thick buried oxide layer can resist a high-temperature severe environment, and an AlN heat dissipation material with a high heat conductivity coefficient is deposited, so that rapid heat dissipation at a high temperature is ensured; and meanwhile, the stability and the reliability of the sensor are improved by adopting leadless packaging, and the packaging density is further optimized.

The invention belongs to the technical field of MEMS resonance sensors, and particularly relates to a real-time liquid flow rate monitoring sensor and method based on an MEMS plane resonance technology. Wherein the fan-shaped sensing plate is an arc plate, a central supporting beam is arranged at the rear end of the middle part of a small arc-shaped edge of the fan-shaped sensing plate, an electrothermal resonance excitation thin beam and a piezoresistive frequency reading thin beam are arranged on the left side and the right side of the fan-shaped sensing plate, and an electrothermal excitation resistor is embedded in the electrothermal resonance excitation thin beam; a piezoresistor is embedded in the piezoresistive frequency reading thin beam; according to the invention, the MEMS resonance technology is applied to the micro flow channel, and the high-precision measurement of the flow velocity of the fluid is realized through the frequency deviation characteristic of the torsional mode resonance generated by electromagnetic excitation under the action of the fluid.

The utility model discloses an MEMS sensor and an electronic atomization device. The MEMS sensor comprises a substrate, a base plate, a first polar plate, a second polar plate and a conductive contact. The first surface of the substrate is provided with a groove, the second surface of the substrate is provided with a Wheatstone bridge circuit, and a bridge arm of the Wheatstone bridge circuit comprises a piezoresistor; the substrate covers the groove to form a sealed cavity; the first polar plate is arranged on the bottom wall of the groove; the second polar plate is arranged on the substrate and is spaced from the first polar plate; the conductive contact is arranged on the substrate and / or the base plate and is electrically connected with at least one of the first polar plate and the second polar plate; the first pole plate and the second pole plate are configured to be capable of repelling or attracting each other under the power-on condition. Through the mode, the deflection of the strain film is always small, so that the problem that the deformation of the substrate does not have ideal linear change with the pressure is well improved, and the detection precision of the MEMS sensor is improved.

The invention relates to a piezoresistive sensor. In particular, the present disclosure relates to piezoresistive sensor elements and piezoresistive pressure sensors that detect mechanical stresses acting on a membrane. The piezoresistive sensor element (100) comprises a substrate which, in operation, is subjected to a mechanical stress in response to a measured variable to be measured, a first array of at least four sensitive varistors (114), where the sensitive varistors (114) are arranged on the substrate and connected to form a first Wheatstone bridge for generating a first bridge signal, and a second array of at least four sensitive varistors (114) arranged on the substrate and connected to form a second Wheatstone bridge for generating a second bridge signal. A second array of at least four insensitive varistors (122), where the insensitive varistors (122) are connected to form a second Wheatstone bridge for generating a second bridge signal, where the stress sensitivity of the sensitive varistors (114) is higher than the stress sensitivity of the insensitive varistors (122), and wherein an output signal of the piezoresistive sensor element (100) is generated based on a difference of the first bridge signal and the second bridge signal.

The invention relates to the technical field of pressure sensors, and discloses a piezoresistive multi-range MEMS pressure sensor and a processing method thereof. The piezoresistive multi-range MEMS pressure sensor comprises: a pressed diaphragm; the mass blocks comprise a central mass block and a fixed mass block; the insulating layer is clamped between the pressed diaphragm and the mass block; the piezoresistor is arranged on one side, deviating from the mass block, of the pressed diaphragm; the at least two supporting frames are located in the pressure groove, each supporting frame surrounds the center mass block and is spaced from the center mass block, the supporting frame adjacent to the center mass block is connected with the center mass block through a first connecting beam, and the supporting frame adjacent to the fixed mass block is connected with the fixed mass block through a second connecting beam; every two adjacent supporting frames are connected through a third connecting beam. The piezoresistive multi-range MEMS pressure sensor disclosed by the invention is simple in structure and easy to process, and not only realizes multi-range acting force detection, but also realizes micro-range high overload measurement.

The utility model relates to a lightning protection and insulation withstand voltage protection circuit, which is characterized in that a circuit is formed by piezoresistors MOV1, MOV2, MOV3 and MOV4, when surge voltage such as lightning stroke and the like exceeds rated voltage, the values of the piezoresistors in a parallel circuit are suddenly reduced to be conducted, high voltage passes through gas discharge tubes G1 and G2, and after lightning transient overvoltage is discharged, the circuit is discharged by a grounding wire. Meanwhile, the resistance value of a piezoresistor MOV5 connected in the LN circuit in parallel is sharply reduced to be switched on, and a fuse Ft is burnt out by instantaneous strong current, so that electric equipment such as an LED power supply and the like is prevented from being damaged. In addition, the technical scheme has a protection mode of lightning protection and discharge resistor combination of resistors R1, R2 and R3, can meet the requirements of lightning protection and high voltage, has the characteristics of no leakage current, no follow current and the like, and effectively prolongs the service life of an LED system.

The invention relates to the technical field of lightning arrester manufacturing, in particular to a method for recycling micro powder for MOA piezoresistor ceramics. The method comprises the following steps: S1) testing the residual amounts of a dispersing agent and a binding agent in the micro powder for the MOA piezoresistor ceramic, and respectively recording the residual amounts as x and y; s2) mixing the micro powder with water, a binding agent and a dispersing agent to obtain slurry; the mass ratio of the micro powder to the water to the binding agent to the dispersing agent is 4000: 2000: (600-y): (20-x); and S3) granulating the slurry until the slurry contains water, and molding to obtain the resistor disc. The method provided by the invention not only reduces the loss of the micro powder, but also improves the utilization rate of the raw materials.

The invention relates to the technical field of stand-by power supply monitoring, in particular to an output stability monitoring method for a stand-by power supply for an elevator, which comprises the following steps of: judging whether the output stability of a power supply to be tested is abnormal or not by connecting a piezoresistor test loop and utilizing temperature change curve comparison conditions of a piezoresistor under different output working conditions; calculating a performance separation characterization index under each output working condition by using the temperature increment curve relative to the ambient room temperature; analyzing and determining a performance local separation power supply according to an index sequence consisting of the performance separation characterization indexes; and finally, determining an abnormal battery pack according to the internal resistance detection result of each battery pack under the determined disengagement characteristic dominant working condition. And furthermore, the output performance fluctuation condition of the battery pack in the switching operation process of different remaining electric quantities is indirectly quantified, and the dynamic guarantee capability of the standby power supply under the full working condition is comprehensively reflected.

The utility model discloses a power supply input surge protection and isolation device, which comprises a piezoresistor, a surge decoupling power resistor and a TVS (Transient Voltage Suppressor) tube which are sequentially connected in series, and a self-adaptive surge control circuit which is connected with the surge decoupling power resistor in parallel, when surge overvoltage occurs, the TVS tube is firstly broken down, and transient large current flows through the adaptive surge control circuit; the surge decoupling power resistor is used for enabling the passing surge current to generate relatively large voltage drop after the TVS tube is broken down; the self-adaptive surge control circuit comprises a first MOS tube which is used for conducting transient large current passing through a TVS (Transient Voltage Suppressor) tube; when the voltage drop on the MOS tube is greater than the breakdown voltage of the voltage-regulator tube, the voltage-regulator tube is broken down to trigger the conduction of the triode; when the voltage-regulator tube is broken down, the triode is conducted, so that the GS voltage drop of the first MOS tube is reduced, and the first MOS tube is turned off; when the sum of the clamping voltage of the TVS tube end and the voltage drop of the surge decoupling power resistor exceeds the minimum action voltage of the piezoresistor, the piezoresistor acts, so that high-energy transient interference flows through the piezoresistor, and surge protection is realized. According to the utility model, the surge protection and isolation protection functions of the input end of the power supply can be effectively realized, and the safety and stability of the use of the power supply are ensured.

The invention provides a method and device for increasing the rated current breaking frequency of a direct-current solid-state circuit breaker and application of the method and device, and aims to solve the problem that the breaking frequency of an existing direct-current solid-state circuit breaker is limited due to over-temperature damage caused by performance degradation after multiple current impacts of a piezoresistor and difficult measurement of the junction temperature of a power device. The system comprises a junction temperature prediction module based on a physical information neural network, an auxiliary energy absorption module and a power device voltage clamping module. The junction temperature prediction module is used for accurately predicting the junction temperature of the power device in real time by fusing a physical thermal model and a neural network; the voltage clamping module suppresses turn-off overvoltage; and the auxiliary energy absorption module is started when the junction temperature is close to the limit to absorb residual energy. According to the design, turn-off energy is reasonably distributed, the impact frequency and strength of the piezoresistor are reduced, the service life of the piezoresistor is remarkably prolonged (for example, the service life is prolonged by about 10 times under the impact of 200A), then the rated breaking frequency of the solid-state circuit breaker is greatly increased, and the solid-state circuit breaker is low in cost, high in reliability and suitable for scenes such as a direct-current power grid.

The invention provides a pressure sensor and a preparation method thereof, the pressure sensor comprises a first wafer, a top semiconductor layer, a lead structure, a lead hole and a conductive column, the upper surface layer of the first wafer is provided with an absolute pressure cavity and an isolation groove; the top semiconductor layer is stacked on the upper surface of the first wafer, the lower surface layer of the top semiconductor layer is provided with a sensor functional area, the edge area of the sensor functional area is provided with four varistors which are uniformly and symmetrically distributed, each varistor comprises at least one resistance area, and the edge and the peripheral area of the sensor functional area are provided with a plurality of connecting areas connected with the two ends of each varistor; the plurality of lead structures are located on the lower surface of the top semiconductor layer and located in the isolation groove, and one end of each lead structure is electrically connected with the connection area; the lead hole is opened from the bottom surface of the first wafer and the lead structure is exposed from the bottom surface; the conductive pillar fills the lead hole. The sensor structure is improved, and the functional area of the sensor covers the opening of the absolute pressure cavity, so that the device is prevented from being influenced by the external environment, and the sensitivity of the device is ensured.

An overvoltage protection device module includes an electrically conductive first electrode, an electrically conductive housing electrode, and a varistor member formed of a varistor material and electrically connected between the first electrode and the housing electrode. The housing electrode includes a housing end wall and a housing side wall collectively defining a housing cavity, and first and second housing members joined together at a joint. The first housing member forms a first portion of the housing side wall and the second housing member forms a second portion of the housing side wall. The varistor member is disposed in the housing cavity.