76 results about "Voltameter" patented technology

The invention relates to the technical field of ammeter fault detection, and provides an intelligent ammeter series arc fault detection method, system and device, a medium and equipment, and the method comprises the steps: firstly obtaining an ammeter data set of an intelligent ammeter, which comprises a pre-ammeter voltage, a post-ammeter voltage and a total loop current in a continuous power frequency period, and then carrying out the division through a sliding time window, obtaining a plurality of ammeter data windows; for each window, calculating a voltage difference sequence and a dynamic loss impedance sequence; when the absolute value of the total loop current is smaller than a preset threshold value, determining the current zero-break interval of each power frequency period and the current zero-break time corresponding to the window; determining an arc voltage estimation value according to a voltage difference between non-zero-break intervals in the zero-break interval; and finally, integrating the current zero break time, the arc voltage estimated value and the dynamic loss impedance of each window to judge whether a series arc fault exists, and if so, triggering a protection action. According to the embodiment of the invention, high-reliability identification of the series arc fault is realized.

The invention discloses a high-thermal-conductivity ultrathin silica gel gasket and a preparation method thereof, and belongs to the technical field of thermal conductive materials. The high-heat-conductivity ultrathin silica gel gasket is prepared from silicon rubber, vinyl silicone oil, MQ silicon resin, a coupling agent, dimethyl silicone oil, hydrogen-containing silicone oil, an inhibitor, a catalyst and heat-conducting powder according to specific mass parts, wherein the heat-conducting powder is prepared by compounding sphere-like aluminum oxide and multi-particle-size spherical aluminum oxide; by accurately controlling the performance parameters of each component and the particle size distribution and mass ratio of the heat-conducting powder, collaborative optimization of the heat-conducting property, the processing property and the structural stability is realized. The heat conductivity coefficient of the prepared high-heat-conductivity ultrathin silica gel gasket is larger than or equal to 5.0 W / (m.K), the thickness can be as low as 0.25 mm, the heat resistance is smaller than or equal to 0.21 K.in / W, the breakdown voltage is larger than or equal to 3.7 kV, needle holes and stripping phenomena do not exist in the surface, and the high-heat-conductivity ultrathin silica gel gasket meets the heat dissipation requirement of precise electronic equipment. The preparation method is simple in process, high in controllability and suitable for industrial production.

A method of measuring ultra-low concentration of a target analyte in a host fluid includes placing a droplet by a micropipette having an ejection tip, positioned by a micro-positioner, configured to position the ejection tip atop a first electrode in electrochemical contact with an electrolyte disposed in a first vessel, such that a droplet having an initial radius comprising of a target analyte in a host fluid can be deposited atop the first electrode, iteratively applying a potential to the first electrode and measuring electrical current between the first electrode and a second electrode in electrochemical contact with the electrolyte based on a predetermined voltage sweep rate, obtaining current vs. voltage curves for each voltameter iteration, identifying redox or oxidation peaks for each voltameter iteration based on a predetermined criterion, and determining target analyte concentration based on the identified redox or oxidation peaks.

The invention relates to the technical field of aerosol generating devices, and discloses a voltameter data processing method and an aerosol generating device. The aerosol generating device comprises a battery cell, a voltameter and a controller, the voltameter data processing method comprises the steps of determining whether to update a target learning data set according to a preset time rule, a current learning data set and the target learning data set stored in a flash memory of the controller, and when it is determined that the target learning data set is updated, determining whether the target learning data set is updated. Updating the target learning data set to be consistent with the current learning data set; and after the voltameter is reinitialized, according to a target learning data set stored in the flash memory of the controller and the current learning data set, determining whether to update the current learning data set, and when it is determined that the current learning data set is updated, updating the current learning data to be consistent with the learning data set. Therefore, the influence that the voltameter is powered down or enters an ultra-low power consumption mode can be avoided, and the accuracy of the remaining power percentage displayed by the aerosol generation device is improved.

The present application discloses a battery system and a power supply system. The battery system comprises a processing circuit, a constant current source and a plurality of battery packs; each battery pack comprises at least one sampling resistor; the sampling resistors of all the battery packs are connected in series across the constant current source; voltages across the constant current source can directly reflect corresponding voltage protection values when different numbers of battery packs are connected in series; the processing circuit is connected across the constant current source, and uses the voltage across the constant current source as a voltage protection value to compare same with a voltage after the plurality of battery packs are connected in series. According to the battery system provided by the present application, the voltage protection value is directly represented by means of the voltage across the constant current source, and there is no need for an installation worker to open a switch box on site to adjust the voltage protection value by means of a DIP switch, thereby achieving convenience and rapidness, improving the safety, and reducing personnel costs.

The utility model discloses a power line conduction emission environment noise testing device. The device comprises a metal box, a passive load module and a fan heat dissipation module. The passive load module is arranged on the upper portion in the metal box, the fan heat dissipation module is arranged on the lower portion in the metal box, and the passive load module and the fan heat dissipation module are separated through a metal partition plate. The passive load module comprises a first connector, an air switch, a plurality of mechanical voltmeters and a plurality of RLC circuits. The fan heat dissipation module comprises a second connector, a switch, a filter and an electric fan. The load has resistance characteristics, capacitive reactance and inductive reactance effects, the impedance of the load can be adjusted, environmental noise under different load impedances can be detected, whether the environmental noise of a laboratory meets the standard test requirement or not can be effectively detected, the test mode is closer to the test mode of a tested product, the test result is more accurate, and the test efficiency is improved. And the interference of environmental noise on the test of the tested product can be eliminated.

The present invention relates to an electronic lock (1) with a battery (3) and emergency energy charge consisting of a power source (2) which is formed by a battery voltage meter (3a), a blocking diode (2a), a capacitor (2b) and a capacitor voltage meter (2b1), which powers a microcontroller (5) and a motor (8) to actuate an actuator (9) that actuates a locking element (10) during its opening or closing movement when an energy switch (6) is actuated. The microcontroller (5) is capable of detecting that the voltage of the battery (3) is less than 3.3 V, by means of the battery voltage meter (3a), allowing the capacitor (2b) to be charged with energy by means of the emergency energy emitting device (7), via an antenna (4) of the electronic lock (1).

The application relates to the field of batteries, in particular to a battery SOC estimation method, an estimation system and a power battery system. The battery SOC estimation method comprises the following steps: A, obtaining a display SOC value by using an ampere-hour integration method; B, detecting a dynamic voltage of a battery charging system, and obtaining a corrected SOC value in a dynamic voltage / SOC matrix table according to the dynamic voltage; and C, comparing the display SOC value with the corrected SOC value, and determining a display mode of the display SOC value according to a comparison result. Compared with the prior art, the battery SOC estimation method provided by the application can obtain a corrected SOC value in a dynamic voltage / SOC table according to a dynamic voltage of a battery system during charging, compare the corrected SOC value with a display SOC value obtained by using an ampere-hour integration method, determine a final display SOC value according to a comparison result, and thus can ensure that the residual capacity of the battery can be accurately fed back before the vehicle starts discharging after being charged, which is a great progress in the field.

The application relates to the technical field of electrostatic detection, and discloses an electrostatic detection equipment for an anti-static protective film, which comprises a test table, a static voltage tester fixedly connected to the top of the test table, a base plate fixedly connected to the top of the test table, a sliding frame slidingly connected to the inner wall of the test table, an extrusion block slidingly connected to the inner wall of the sliding frame, and an electric telescopic rod II. The electric telescopic rod II is started to extend, a connecting frame is pushed to move, a gas pressure frame and a connecting rod are driven to move, the connecting rod is extruded upwards by the extrusion of the concave plate and the convex plate, a spring piston block is driven to rise, a lifting assembly and a discharge assembly are used to generate negative pressure in the gas pressure frame, bubbles between the protective film and the base plate are simultaneously attracted, the bubbles move towards the edge area of the protective film, the bubbles are discharged, the bubbles remaining between the protective film and the base plate are effectively prevented, the peeling process of the protective film is not unstable, the generated static voltage is not greatly fluctuated, and the accuracy of detection data is ensured.

The invention discloses an FCA-UKF lithium battery pack SOC estimation method comprising the following steps: providing a dynamic weighted voltage characterization method to construct a virtual unit model of a lithium battery pack, and through the virtual unit model, significantly reducing the calculated amount, adapting to battery inconsistency, and ensuring efficient and accurate SOC estimation; selecting an equivalent circuit model, and establishing a system state space equation; on the basis of HPPC working condition test data, model parameters are identified in combination with a least square method with a forgetting factor; and estimating the SOC of the whole battery pack in combination with a virtual unit model. According to the method, a fuzzy covariance adaptive unscented Kalman filter (FCA-UKF) algorithm is provided, the process noise covariance is adaptively adjusted on the basis of the unscented Kalman filter algorithm, the difference value between the actual variance and the theoretical variance of the measured noise is monitored in real time in combination with a fuzzy controller, real-time online adjustment of a measured noise covariance matrix is achieved, and the real-time online adjustment of the measured noise covariance matrix is achieved. The accuracy and stability of state estimation can be improved while the filtering precision is ensured.

The application relates to a low-voltage distribution network topology identification method based on weighted Mahalanobis distance and granularity clustering, which comprises the following steps: collecting the voltage sequence of each user's electric meter box under each block as a sample point; using an improved weighted Mahalanobis distance to calculate the weighted Mahalanobis distance between each voltage meter sequence; calculating the density between the sample points according to the weighted Mahalanobis distance between two voltage meter sequences; for each sample point, constantly obtaining the sample point closest to the current sample point and having increased density, clustering, determining the clustering center, and discriminating the block to which the user belongs according to the clustering result. Compared with the prior art, the application is simple to realize, only needs to measure the voltage data of the smart electric meter, does not need to increase additional measuring equipment in the system, and the calculation result of the weighted Mahalanobis distance is more relevant and can better reflect the similarity relationship between the data.

This invention relates to a method and apparatus for measuring the voltage of a secondary battery. Existing methods for assessing the state of charge (SOC) of a battery can only be performed when the battery is not in operation, and therefore cannot reflect the battery's true SOC. This method involves connecting the positive and negative electrodes of the secondary battery to a first voltmeter to measure a first voltage; placing a positive-side voltage measuring probe on the positive electrode side of the secondary battery, and symmetrically, placing a negative-side voltage measuring probe on the negative electrode side; connecting the positive and negative-side voltage measuring probes to a second voltmeter to measure a second voltage; and taking the average of the first and second voltages as the measured voltage value of the secondary battery for assessing its remaining capacity. This invention enables rapid, accurate, and effective measurement of the secondary battery voltage while it is in operation, thereby allowing for more precise management of the energy storage of the secondary battery.

The invention discloses a discharge cut-off voltage control method and system of a single battery and a vehicle. The discharge cut-off voltage control method comprises the steps that the degradation capacity Closs of the single battery and the dischargeable capacity CV0 corresponding to V0 are obtained; if yes, the discharge cut-off voltage is reduced by delta V; if yes, the discharge cut-off voltage is kept unchanged; and when the discharge cut-off voltage is less than or equal to Vmin, stopping reducing the discharge cut-off voltage. Wherein V0 represents the preset initial discharge cut-off voltage, X1 represents the preset first attenuation rate, delta V represents the preset voltage reduction amplitude, and Vmin represents the preset minimum discharge cut-off voltage. According to the invention, the service life of the battery can be prolonged, and the cost is controlled within a reasonable range.

A frame is installed on the periphery of a light-transmitting plate, a group of opposite side edges of the frame are provided with two groups of translation grooves with corresponding heights, the two groups of translation grooves are arranged above the light-transmitting plate and are arranged up and down, and two ends of two clamping rods are respectively connected in the group of translation grooves at the lower side. The probe plate is connected in one group of translation grooves on the upper side, an ampere meter terminal and a voltmeter terminal are led out from the probe plate, the other group of opposite side edges of the frame are respectively connected with a support column on the base through a shaft, and a handle is arranged at the outer end of the shaft. When the positive electrode and the negative electrode are both designed on the same face of the battery and on the two faces of the battery respectively, compatible fixation is conducted on the solar battery during IV testing, the battery is fixed through the movable clamping rod, the probe plate is installed on the movable moving rod, flexible adjustment can be achieved, the solar battery fixing device is particularly suitable for fixing small-size batteries, the batteries are firmly fixed, and the working efficiency is improved. And the overturning of the test bench does not affect the clamping and fixing of the battery.

A lifting mechanism is installed on a base, a cooling device is arranged above the lifting mechanism and fixed with the lifting mechanism, a carrying table comprises an insulating plate on the lower layer and a conductive plate on the upper layer, the carrying table is arranged above the cooling device and fixed with the cooling device, and a test board is located above the carrying table; a conductive flat cable of the test board is located on the lower surface of the light-transmitting plate, an ampere meter terminal and a voltmeter terminal are led out from the conductive flat cable, the battery is placed on the conductive plate with the light-receiving surface facing upwards, all grid lines on the back surface of the battery are in contact conduction with the conductive plate, the lifting mechanism ascends, and the grid lines on the light-receiving surface of the battery are in contact conduction with the conductive flat cable; and the electric control cabinet is provided with a temperature controller and a temperature control switch associated with the cooling device, a lifting switch associated with the lifting mechanism and an associated power supply. When the positive electrode and the negative electrode are respectively designed on the two surfaces of the cell, the device is suitable for compatible fixation of solar cells with different electrode patterns, sizes and thicknesses during IV testing.

The invention relates to an electricity stealing quantity calculation method and device based on a data acquisition device. The method comprises the steps of setting a data acquisition device, acquiring first current data based on the data acquisition device, and calculating a medium-voltage side current actual consumption value based on the first current data; voltage data, second current data and meter active power corresponding to the collection time point of the first current data are obtained based on a metering general meter, and a medium-voltage side ammeter consumption value is obtained through calculation based on the second current data; a current difference value between the medium-voltage side current actual consumption value and the medium-voltage side ammeter consumption value is obtained, whether the current difference value is larger than a current difference threshold value or not is judged, and when the current difference value is larger than the current difference threshold value, it is judged that the first collection time point of the current data is the electricity stealing time point; and when the acquisition time point of the first current data is the electricity stealing time point, calculating to obtain a medium-voltage side voltmeter back calculation value based on the voltage data. In this way, not only can the specific electricity stealing time be determined, but also the specific electricity stealing quantity can be determined.

The utility model relates to a device for measuring the contact resistance of a spherical furnace charge, which is suitable for testing the resistance of a low-resistance furnace charge in a metallurgical production process. The device comprises an insulating cylinder, a first adjusting plate and a second adjusting plate which are in sliding fit with the two ends of the insulating cylinder respectively. Four contact pins are arranged on the two adjusting plates, the first contact pin and the third contact pin are used for being connected with a voltmeter, the second contact pin and the fourth contact pin are used for being connected with an ampere meter, and a four-wire method testing loop is formed. The spherical furnace charge is placed between the two adjusting plates, and the contact pin is in stable contact with the surface of the furnace charge through sliding of the adjusting plates, so that the contact resistance of the spherical furnace charge is accurately measured. The device can reduce the influence of the lead resistance on the measurement precision, is suitable for measuring the contact resistance of spherical furnace charges with different particle sizes or different components, and is beneficial to improving the temperature uniformity and the energy utilization efficiency in the smelting process. The device is simple in structure, convenient to operate, high in adaptability and high in application value.

The invention relates to the technical field of lithium battery management, in particular to a negative-end high-voltage isolation circuit for voltameter communication, which is applied to a battery pack comprising a battery pack, a voltameter IC (integrated circuit), a protection IC and a negative-end switch MOSFET (metal-oxide-semiconductor field effect transistor) controlled by the protection IC. The control module outputs a control signal according to the level state of the discharge control output end; the high-voltage isolating switch unit is connected in series on a communication line between the communication pin of the voltameter IC and the external communication interface; when the discharge control output end indicates that discharge is allowed, a control signal output by the switch control unit enables the high-voltage isolation switch unit to be conducted; when the discharge control output end indicates to turn off discharge due to protection action, a control signal output by the switch control unit turns off the high-voltage isolation switch unit so as to cut off a communication line and isolate the impact of high voltage generated at the load negative end P-due to turn-off of a discharge switch tube on the voltameter IC.

The application discloses a power battery SOC estimation method based on battery monomer voltage, and the main design concept of the application is that the characteristics of end pressure difference amplification of a battery pack with poor monomer consistency are utilized, the actual SOC maximum and minimum values are estimated based on the maximum and minimum values of the monomer voltage and the rated capacity, and the actual power value in the actual charging and discharging process is estimated by using the weighted summation of the two. Meanwhile, in the process of continuously obtaining the actual power value, the pre-calibrated monomer voltage OCV table is inquired according to the set power interval and the charging and discharging current threshold, so that the actual SOC maximum and minimum values participating in the estimation are corrected in real time, that is, the actual power estimation value is continuously corrected based on the calibrated monomer voltage value in the charging and discharging process, so that the actual SOC of the battery pack can be accurately calculated when the monomers of the battery pack have large differences, and the charging and discharging capacity of the battery pack can be accurately reflected.

The invention provides an electric quantity balance correction method of a chip without a voltameter and an electronic device, and the method comprises the following steps: triggering to enter a preset state, and taking the current voltage conversion electric quantity as a set value of integral electric quantity; the measurement current and the voltage conversion electric quantity are updated at intervals of a preset time period, the correction current is updated according to the updated measurement current and the updated voltage conversion electric quantity, the integral electric quantity is updated according to the updated correction current, and the charge state is updated according to the updated integral electric quantity. Calibration of voltage conversion electric quantity and calibration covering different key nodes are achieved according to triggering entering the preset state, the accuracy of final charge state calculation is improved, the difference between the voltage conversion electric quantity and the integral electric quantity is evenly allocated to the remaining life cycle based on conversion of the correction current, and jumping of the determined charge state is avoided. According to the method, more accurate charge state calculation is realized on the premise of limited resources.

An ammeter measures current when a storage battery having a plurality of single batteries connected in series is charged or discharged. A voltmeter measures total voltage of the storage battery. A calculation device calculates dV / dt obtained by differentiating the total voltage with respect to time on the basis of a relationship between the total voltage and charging time or discharging time, separates a characteristic peak obtained by a dV / dt curve into peaks for the respective single batteries, and diagnoses soundness of the storage battery on the basis of the separated peaks.

The utility model relates to the technical field of teaching demonstration appliances, and provides a hydroelectric generation demonstration device for teaching, which comprises a fixed box. The indicating lamp, the ampere meter and the voltmeter are fixedly connected to one side of the front face of the fixed box, a cavity is formed in the fixed box, the upper end of the inner wall of the cavity is rotationally connected with a water turbine, the lower end of one side of the fixed box is fixedly connected with a drainage pipe, and the upper end of the other side of the fixed box is fixedly connected with a generator; the water storage tank is arranged above the fixed tank, and one end of the bottom end of the water storage tank is fixedly connected with a blow-off pipe; the filtering assembly is assembled at the top end of the water storage tank; the height between the bottom end of the blow-off pipe and the water turbine can be changed through the arranged adjusting assembly, the water flow discharge amount is achieved through a valve on the blow-off pipe, then different demonstration of the power generation amount by different water flows and heights can be achieved, and the corresponding teaching demonstration effect is improved.

The utility model provides a traceability device for electric vehicle power battery detection equipment, which belongs to the technical field of traceability of power battery detection equipment and comprises a load module, a voltameter and a voltage / current sampling module. Electric energy released by the electric vehicle power battery detection equipment in the traceability process is consumed through the load module; the voltameter is connected with the charging gun and is used for collecting electric quantity consumed by the load module; the voltage / current sampling module is connected with the charging gun and is used for collecting voltage data and current data transmitted to the load module by the charging gun in the traceability process. According to the utility model, the traceability of the power battery detection equipment of the electric vehicle is realized and the accuracy of the detected quantity value is verified without disassembling the whole vehicle and changing the control strategy, so that the detection data among different power battery detection equipment of the electric vehicle has a unified standard.

The invention discloses an early warning system for damage of materials in a high-temperature furnace or a graphitization furnace. The early warning system is suitable for the high-temperature furnace provided with an opposite-penetrating type graphite heater and a multi-layer carbonaceous heat preservation layer. According to the system, the center temperature of a hearth is obtained through an optical pyrometer arranged outside a furnace body, temperature sensors are arranged in heat preservation layers with different thicknesses to obtain the temperature of each heat preservation layer, current transformers or Rogowski current loops are arranged at the head and the tail of a graphite heater, and a low-voltage alternating-current voltmeter is connected to a heating loop; collecting the temperature in the furnace, the temperature of each insulating layer and the current, voltage and power data of a heater; the method comprises the following steps: establishing a heat preservation characteristic reference curve corresponding to furnace temperature and different heat preservation thicknesses in the initial heating stage of equipment, comparing real-time data with the reference curve in the operation process, distinguishing abnormal short circuit and normal aging of a heat preservation material by combining head and tail current distribution and resistance change of a graphite heater, and evaluating equivalent loss of a graphite piece. The system records multi-dimensional data for a long time through the PLC and the upper computer, predicts the residual life of the thermal insulation material and the heater, and realizes online diagnosis and early warning of the state of the material in the furnace.

The application relates to the technical field of lead-acid battery shell detection devices, and provides a lead-acid battery shell detection mechanism, which comprises a detection seat, a detection assembly is arranged on the detection seat, the detection assembly comprises first probes and second probes, the first probes are electrically connected with a constant-current power supply, the first probes are electrified to welding points, the second probes abut against the welding points and are electrically connected with a voltmeter, and the voltage of the welding points is tested. Based on the mechanism, the welding points after wall penetration welding can be detected, and whether there is lead explosion or impurity residue can be judged.

The utility model discloses a battery module, and belongs to the technical field of batteries, the battery module comprises a battery body, a voltameter, a display screen and a wireless communication device, the voltameter, the display screen and the wireless communication device are installed on the battery body, the voltameter and the display screen are electrically connected with the battery body, and the wireless communication device is electrically connected with the battery body. The voltameter is used for detecting the residual electric quantity of the battery body, the voltameter is in communication connection with the display screen, the display screen is used for displaying the residual electric quantity of the battery body, and the wireless communication device stores parameter information of the battery body. According to the battery module, the problems that the consistency of patterns formed on the surface of the battery is poor and the patterns are easy to abrade along with the increase of the use time because the current battery generally adopts a silk-screen mode, so that a user cannot accurately obtain corresponding information can be solved.

An embodiment of the present invention discloses a method for estimating the battery charge level, which first calculates the state of charge of the battery during the charging process using the Coulomb integration method until the battery enters the floating charge mode, and establishes a charging voltage table and a charging current table based on the state of charge and its corresponding charging voltage and charging current. After the battery is left at rest, the first current resting open-circuit voltage of the battery is measured. According to the current state of charge of the battery, the corresponding lookup charging voltage is found from the charging voltage table, and according to the current state of charge, the corresponding lookup charging current is found from the charging current table, and the voltage difference between the lookup charging voltage and the first current resting open-circuit voltage and the lookup charging current are recorded. Finally, the first resting state of charge of the battery is determined based on the current state of charge, the first current resting open-circuit voltage, the voltage difference, and the lookup charging current.

The embodiment of the invention provides an information processing method and electronic equipment, the electronic equipment comprises a first battery, a charging module and a first voltameter, the charging module is used for charging the first battery, and the first voltameter is used for measuring the electric quantity of the first battery; the method comprises the following steps: when the first voltameter detects that the electric quantity of the first battery is fully charged, controlling the charging module to stop charging the first battery; and / or, when the charging module detects that the first battery is fully charged, the first voltameter is controlled to set the electric quantity of the first battery to be fully charged. According to the embodiment of the invention, the problem that the real-time battery electric quantity displayed in the electronic equipment is inconsistent with the battery charging state can be solved, and the user experience is improved.

The invention relates to the technical field of power supply performance detection, and provides an equipment power supply performance detection device and method, and the device comprises a lifting mechanism, a driving mechanism, a bearing mechanism, and a transmission mechanism. In the continuous rotation process of a small gear on a driving mechanism, a large gear can obtain a transient static state after rotating for a circle, so that a conveying belt stops conveying, at the moment, a transmission frame drives a right-angle rod to be just at the lowest height, and a detection feeler lever abuts against an electrode on an equipment battery; therefore, the voltage of the equipment battery can be rapidly detected through the voltmeter, at the moment, the bearing mechanism just ascends to the highest position, the bottom of the equipment battery in the detection state can be supported through the supporting plate, the detection work can be stably carried out, operation is easy, use is convenient, and practicability is high. The detection work can be carried out by only one motor, the cost is saved, the automation degree is high, the working efficiency is greatly improved, and the use value is very high.

The utility model discloses a water conservancy detection device with an emergency power supply function, and particularly relates to the technical field of water conservancy detection, the water conservancy detection device comprises a support plate mounted on a support column, and a detection piece used for water conservancy detection is arranged outside the support column; an electric power storage part for emergency power supply is arranged outside the supporting plate; the power storage part comprises a box body installed at the top of the supporting plate, a storage battery is installed in the box body, a switch knob and a voltmeter are installed at the top of the storage battery, the voltmeter is arranged on one side of the switch knob, the switch knob is sleeved with a gear, and the rear end of the gear is meshed with a toothed plate. According to the utility model, the storage battery is used as a standby energy source, so that the electromagnetic plate is not electrified and does not contract the spring under the special conditions of power failure and the like, thereby facilitating outward movement of the toothed plate on the movable column by virtue of the resilience force of the spring, and driving the switch knob to rotate by the toothed plate through meshing with the gear, thereby realizing the effect of opening the storage battery for emergency power supply; and the whole structure is stable in power supply.