4206 results about "Cut-off" patented technology

Provided in the present invention is an interference-factor-based high-safety and stable control method for an onboard magnetically suspended flywheel battery system. The method comprises: in the case of a safe operating condition interference, obtaining the difference between a displacement reference signal and an actual displacement signal, and inputting the difference into a Butterworth-filter-fused fuzzy active disturbance rejection control module, so as to obtain control currents, wherein the control currents comprise a radial control current, a torsion control current and an axial control current; the radial control current and the torsion control current are subjected to Clark inverse transformation, and the axial control current is subjected to power amplification, and the three currents are then compensated for, such that a three-phase control current of a radial coil, a three-phase control current of a torsion coil, and a control current of an axial coil are obtained; the control currents control the corresponding coils, and are also input into a multi-information extended Kalman filtering prediction module, such that the actual displacement signal is output; and in the case of a dangerous operating condition interference, cutting off an output signal from an operating condition recognition and safety determination module. The present invention can improve the stability, robustness and anti-interference capability of a system.

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 provides an excitation fuse with active and passive integrated protection and a related device. The excitation fuse is applied to a protected circuit. The active and passive integrated protection excitation fuse comprises a fuse shell, an impact device, a first melt, a second melt, a first conductor, a second conductor and at least one excitation source, the excitation fuse is connected in series in a protected circuit through the first conductor and the second conductor; the first melt and the second melt are connected in parallel between the first conductor and the second conductor; when the voltage of the first melt is higher than the trigger voltage of any excitation source in the at least one excitation source, the corresponding excitation source is triggered to release high-pressure gas into the penetrating cavity; or any excitation source in the at least one excitation source releases the high-pressure gas into the penetrating cavity when receiving the control signal of the control circuit; and then the impact device is pushed to impact the first melt and / or the second melt along the movable cavity so as to cut off the first melt and / or the second melt.

The invention discloses a power-on reset circuit, and relates to the technical field of integrated circuits, in order to eliminate static power consumption of the power-on reset circuit and reduce power consumption of the power-on reset circuit, the power-on reset circuit comprises a discharge delay circuit, a current mirror circuit and a buffer circuit; the discharge delay circuit comprises a capacitor and an NMOS (N-channel Metal Oxide Semiconductor) tube M4, and the NMOS tube M4 is used for discharging the capacitor; the current mirror image circuit comprises an NMOS tube M2, an NMOS tube M3 and a PMOS tube M9. The grid electrode of the NMOS tube M2 and the grid electrode of the PMOS tube M9 are respectively connected with the output end of the buffer circuit; the grid electrode of the NMOS tube M3 is respectively connected with the source electrode of the PMOS tube M9, the drain electrode of the NMOS tube M2 and the grid electrode of the NMOS tube M4; the current mirror image circuit is used for turning off the NMOS tube M2 after the reset signal is ended, and pulling up the drain electrode voltage of the NMOS tube M3 to the power supply voltage through the PMOS tube M9, so that the NMOS tube M3 enters a deep linear region, and a direct current path from the power supply to the ground in the current mirror image circuit is cut off; and the buffer circuit is used for outputting a reset signal according to the voltage change of the capacitor in the discharge delay circuit.

The invention discloses a protection circuit, a control method and a photovoltaic system, and belongs to the technical field of power electronics. The invention provides a protection circuit which is applied to a three-phase inverter circuit, the direct current side of the three-phase inverter circuit is used for being connected with a power supply assembly, the output end of each phase is provided with a relay assembly, and the protection circuit comprises a controllable power device which is connected with a bridge arm in the three-phase inverter circuit in parallel; the fault detection module is electrically connected with the three-phase inverter circuit and is used for generating a fault signal when the fault of short circuit to ground is detected; the current detection circuit is used for detecting the output current of each phase of the three-phase inverter circuit; and the controller is electrically connected with the fault detection module, the current detection circuit and the relay, controls the controllable power device to be switched on after receiving a fault signal, and disconnects the relay assembly of each phase when the output current of each phase meets a zero-crossing condition, so that the relay assembly can be ensured to be switched off safely, and a loop of short-circuit current can be cut off. And the short-circuit current is prevented from damaging components in the circuit.

The invention provides a wireless charging power-off protection method for detecting metal foreign matters based on signal change, which comprises the following steps: monitoring magnetic field change through a Hall effect sensor, detecting temperature abnormity in combination with a temperature sensor, carrying out real-time data processing by utilizing an embedded MCU, and automatically entering a calibration mode before charging each time; the method comprises the following steps: acquiring stable magnetic field distribution as a reference value, tracking magnetic field change by using a self-adaptive filter, continuously monitoring magnetic field intensity change in a charging process, comparing the magnetic field intensity change with the reference value, judging whether the magnetic field intensity change exceeds a normal range or not by setting a threshold value, immediately cutting off a power supply and giving an alarm to a user if foreign matters are detected, and after the user confirms that the foreign matters are removed, stopping charging. According to the method, the foreign matters can be accurately detected in different environments through dynamic threshold adjustment and feature optimization, so that the safety of wireless charging and the user experience are improved.

The invention provides a semiconductor device with a PN junction and a preparation method thereof, and belongs to the technical field of semiconductor devices. The semiconductor device comprises a silicon substrate, the surface of one side of the silicon substrate in the thickness direction is provided with an emitter region covering an emitter and an isolation region formed by removing the emitter, a PN junction is formed between the emitter and the silicon substrate, the isolation region is arranged at the edge of the silicon substrate, and at least one side wall of the silicon substrate in the length direction is provided with a cutting surface. An isolation region is arranged at least close to the edge of the cutting surface in the silicon substrate, the surface height of the isolation region is lower than that of the emitter region, the isolation region and the emitter region are connected through a buffer region of a slope structure, and passivation layers cover the surfaces of the emitter, the isolation region and the buffer region. According to the invention, the structure of the isolation region is optimized, a transmission channel of carriers from the emitter region to the cutting surface is effectively cut off, and uniform coverage of the passivation layer is ensured, so that the performance of the device is optimized.

The invention belongs to the technical field of valves, and particularly relates to a pneumatic on-off and back-suction integrated valve for quantitative gluing of semiconductors and a working method thereof.The pneumatic on-off and back-suction integrated valve for quantitative gluing of semiconductors comprises a valve body, a back-suction diaphragm and an on-off diaphragm are arranged above and below a flow channel respectively, and a back-suction diaphragm and a back-suction diaphragm are arranged above and below the flow channel respectively; the lower cavity bottom plate is connected with the lower end of the valve body, a lower piston connected with the on-off diaphragm is arranged in the lower cavity bottom plate, and the lower piston drives the on-off diaphragm to ascend through elastic force so as to cut off the flow channel; and the air cylinder body is connected with the upper end part of the valve body, and an upper piston connected with the back-suction diaphragm is arranged in the air cylinder body. And the lower piston descends to squeeze gas in the cavity below the lower piston into the annular cavity below the on-off diaphragm, so that the on-off diaphragm is buffered, and the impact force borne by the on-off diaphragm is reduced.

The invention belongs to the field of overvoltage protection, and relates to an overvoltage stabilizing and protecting device which comprises a data acquisition operation module, a control logic module, a display module, an overvoltage protecting assembly and a high-voltage vacuum circuit breaker or an electric isolation handcart structure. The real-time monitoring and protection of the working state of the overvoltage protection assembly are realized; through the arrangement of the high-voltage circuit breaker or the electric isolation handcart, when the overvoltage protection assembly is detected to be abnormal, the connection between the overvoltage protection assembly and the high-voltage bus can be rapidly cut off, so that the system safety is ensured; the device integrates a transient fault recording function and can capture wave map data before and after a power frequency overvoltage fault of the system; the overvoltage protection assembly in the device adopts a geometric center air cooling heat dissipation mode, the fan is quick in starting response, the operating temperature of the overvoltage protection assembly is greatly reduced, the operating time of the overvoltage protection assembly can be effectively prolonged, and the device adopts an integrated modular structural design, so that the operation safety, the maintenance and the management are greatly facilitated.

The invention discloses a remote ignition control system for a release flare, and relates to the technical field of release flare control, the system comprises the following components: a fault detection module, a fault isolation module, a standby module, a redundant circuit switching module, a fault diagnosis module and a wireless communication module; by integrating multiple modules of fault detection, fault isolation, standby module and redundant circuit switching, fault diagnosis and wireless communication, comprehensive remote monitoring and management of the release flare ignition control system are achieved, when the system detects a fault, electrical connection of a fault component can be rapidly cut off, and the safety of the release flare ignition control system is improved. And the standby module or the redundant circuit is automatically switched, so that the continuous and stable operation of the system is ensured, the reliability and the safety of the system are remarkably improved, and the risk of production interruption caused by faults is reduced.

The invention relates to the technical field of power system fault protection, in particular to a power distribution network distance protection method, system and device considering distributed power supply negative sequence currents, and aims at a medium-voltage power distribution network where a plurality of distributed power supplies are connected in a feeder line T-connection mode. Considering the influence of negative-sequence current output under negative-sequence current control of a distributed power supply in each feeder line on measured impedance, the feeder line with a two-phase short-circuit fault in the power distribution network is identified and positioned through cooperation of additional impedance compensation and distributed power supply negative-sequence reconstruction control, and then a protection device is controlled to cut off the fault feeder line. And implementing distance protection of two-phase short circuit of the power distribution network. The method realizes fault identification and positioning only by depending on locally acquired electrical quantity parameters, does not need to depend on a communication system, considers and ensures autonomy and reliability of distance protection, has the advantages of simple principle, low cost and high reliability, and can adapt to power distribution networks with different fault positions and different distributed power supply access numbers and capacities.

The invention relates to the technical field of transmitters, and discloses an intelligent monocrystalline silicon pressure difference transmitter which comprises a sensor, diaphragms are arranged on the left side and the right side of the sensor, a first process flange is installed on the front side of the sensor, a second process flange is installed on the rear side of the sensor, and a machine body is fixedly connected to the upper surface of the sensor. A displayer is installed on the front side of the machine body, the sensor is electrically connected with the machine body, and an overload plugging device is arranged on the inner wall of the second process flange. The overload plugging device comprises a U-shaped guide frame, the U-shaped guide frame is installed on the inner wall of the second process flange, and the inner wall of the U-shaped guide frame is connected with a connecting rod in a sliding mode. According to the invention, through the arrangement of the overload plugging device, the interface part can be cut off when the tested pressure end of the transmitter is subjected to overlarge instantaneous pressure, so that the impact of the instantaneous pressure on the diaphragm of the tested pressure end is reduced, and the protection performance of the transmitter on the large instantaneous pressure is improved.

The invention provides a gateway power supply circuit, a circuit board and edge gateway equipment, relates to the technical field of electronic circuits, and solves the problem of poor stability of the edge gateway equipment in the related art. The gateway power supply circuit realizes real-time monitoring of a main power supply voltage, and once it is detected that the main power supply voltage exceeds a preset safety range, the edge gateway equipment can be switched off. When the power supply fails, the system immediately triggers a power supply switching mechanism and seamlessly switches to the auxiliary power supply to supply power, so that the downtime of equipment caused by power supply failure is greatly shortened, and the continuity and the stability of the system are ensured. And when the power supply is suddenly interrupted, the power supply of a key circuit can be quickly cut off, and the power supply can be used as a back-up power supply to quickly provide electric energy support through a high-performance super capacitor, so that key data is not lost, and the data safety and integrity of the system are effectively protected.

The invention discloses a multiband high-voltage power supply control system and a normalization control and protection method thereof, and relates to the technical field of power supply control, and the method comprises the steps: collecting multi-mode signals of S, C and Ku band high-voltage power supply systems and a cooling system; an SDAE deep network and an integrated learning AdaBoost framework are combined to construct a fault diagnosis model, and a fault type and confidence are obtained according to signal features; when a fault occurs, high-voltage output of a corresponding power supply unit is cut off and reported through an isolation interface, and a deep reinforcement learning agent is used for carrying out protection action intelligent decision making; a digital twinborn model of a power supply unit is constructed, an improved grey wolf optimizer is used for multi-task collaborative optimization, optimized system parameters are acquired and issued to a PLC for execution, and waveband output stability is ensured. According to the invention, high reliability, rapid response and intelligent operation and maintenance of the multi-band high-voltage power supply system are realized through deep integration of multi-source signal acquisition, intelligent fault diagnosis, adaptive protection decision and digital twinning optimization.

The invention relates to the technical field of power distribution automation auxiliary power supply control, and discloses an intelligent power distribution circuit system for a digital ring main unit, which comprises a transient voltage gradient induction bridge circuit, a hardware signal processing circuit, a power switch unit and a controlled energy release unit, according to the system, a transient voltage gradient induction bridge circuit is used for collecting a primary side bus voltage change rate signal, a hardware signal processing circuit carries out derivation operation on an induction signal and compares the induction signal with a voltage gradient threshold value, and a power switch unit is blocked at the moment that the voltage abnormally drops so as to cut off a load current path. According to the invention, a hardware parameter direct mapping mechanism is utilized to realize microsecond transient protection response, and the physical decoupling of protection logic and digital software is realized by balancing bus potential pulse caused by sudden unloading of a load through the inherent dehumidification resistor in the multiplexing cabinet.

The invention provides a fault-tolerant control method and a fault-tolerant control system for a dual-active bridge series resonant converter (DBSRC), and aims to solve the problems that the voltage and current stress is increased, the system reliability is reduced and the like caused by an open-circuit fault of a primary side switch tube or a secondary side switch tube. Through the dynamic reconstruction modulation strategy and the same bridge arm driving follow current suppression method, under the condition that redundant hardware is not needed, the voltage and current stress in the fault state is effectively reduced, and stable operation of the system is maintained. The method specifically comprises the following steps: when a primary side open-circuit fault occurs, optimizing a control parameter by adopting extended phase shift modulation (EPS), and compensating for loss of a power transmission path; and when the secondary side has an open-circuit fault, the driving signal of the other switching tube of the same bridge arm is cut off, and the direct-current bias of the resonance current is eliminated. According to the method, the fault-tolerant capability of the DBSRC is remarkably improved, the hardware cost and the maintenance complexity are reduced, and the method is suitable for a high-frequency isolation direct-current conversion system.

The invention provides an intelligent socket control system and method based on an overvoltage and undervoltage protector, and relates to the technical field of intelligent socket control. Load bias utility of an intelligent socket under different working conditions is extracted, load attribute identification is performed on voltage state information, and a load identification tag of a load side in an intelligent socket access circuit is generated; determining a voltage out-of-limit level of the voltage at the front end of the intelligent socket in an overvoltage and undervoltage state; after the dissimilatory breaking criterion is executed to cut off a load power supply loop, a reset response strategy corresponding to the voltage at the front end of the intelligent socket is generated, and then a tolerance adaptation rule of the voltage at the front end of the intelligent socket when the overvoltage and undervoltage fault is removed is determined; and performing adaptive resetting on the power supply planning table of the power supply state in the current intelligent socket access circuit according to the voltage out-of-limit level and the tolerance adaptation rule. According to the invention, differentiated adaptive control can be carried out on load power supply under the activation of an overvoltage and undervoltage protection mechanism, so that the adaptability of the intelligent socket to complex working conditions is improved.

The invention relates to the technical field of direct-current circuit breaker manufacturing, in particular to a direct-current circuit breaker with a rapid current suppression capability and a working method of the direct-current circuit breaker. The main branch is a line from the L side to the R side and sequentially passes through a secondary side winding N2 of the coupling inductor and a pair of anti-parallel thyristors. Each of the four charging branches comprises a diode and is matched with a resistor of the charging resistor branch to provide a charging loop for two capacitors in the two capacitor branches, and two buffer branches are respectively connected in parallel with the two capacitor branches. After a thyristor of the trigger branch is triggered, a capacitor of the capacitor branch can transmit energy to N2 in the main branch through a primary side winding N1 of a coupling inductor in the energy transfer branch, and then bidirectional current is cut off. The direct-current circuit breaker is designed by using the coupling inductor and the thyristor, and the direct-current circuit breaker has the advantages of high efficiency, rapid current suppression, good controllability, reprotection after reclosing, low cost and high reliability in the current breaking process.

A high-linearity grid voltage bootstrap circuit relates to the technical field of analog-to-digital conversion and comprises a first charge pump boosting unit, a second charge pump boosting unit and a grid voltage bootstrap unit, working states of a sampling switch are divided into a sampling state and a holding state, an input voltage VIN is boosted to a VG through the grid voltage bootstrap unit in a sampling stage, and the sampling switch is switched on; and the holding stage sampling switch is cut off, and charges are injected to the upper polar plates of the capacitors C3 and C4 of the gate voltage bootstrap unit through the first charge pump boosting unit and the second charge pump boosting unit respectively. According to the invention, the problem that the actual gate-source voltage is reduced due to the grid parasitic capacitance of the sampling switch is solved, and the layout area occupation is greatly reduced while the bootstrap voltage is improved; the proportion of the capacitor C3 and the capacitor C4 can be flexibly set to obtain the required bootstrap voltage; and the problem that the on-resistance of the sampling switch is increased due to the reduction of the gate-source voltage can be solved, and the linearity of the sampling switch is improved.

The invention provides an intelligent fuse, and belongs to the technical field of circuit protection, and the intelligent fuse is characterized in that an upper housing is provided with at least one excitation chamber, the excitation chamber is internally provided with at least one excitation part and at least one impact part, and the excitation part releases high-pressure gas when receiving any one of an external trigger signal and an internal trigger signal; the lower shell is provided with at least one cooling cavity; the current-conducting plate is arranged between the upper shell and the lower shell, and the impact part moves towards the direction where the cooling cavity is located under the thrust action of the high-pressure gas so as to cut off the current-conducting plate; the self-control module is arranged outside the shell and comprises a current detection unit and a processing unit, and the current detection unit is used for detecting a current signal on the conductive plate; the processing unit is used for generating an internal trigger signal according to the current signal. The beneficial effects of the invention are that a dual-trigger mechanism and redundancy design of an internal trigger signal and an external trigger signal are adopted, so that normal action can still be ensured when any signal fails, and the breaking reliability is improved.

The utility model discloses a low power consumption circuit and a refrigerator. The low power consumption circuit comprises a main control circuit; the power supply circuit comprises a live wire terminal, a zero line terminal, a filter capacitor and a rectifying circuit; the discharging circuit comprises a switching circuit, an optocoupler bidirectional silicon controlled rectifier and a discharging resistor; a switching path of the switching circuit is connected in series in a power supply loop of a light-emitting end of the optocoupler bidirectional silicon controlled rectifier, one end of a light-receiving end of the optocoupler bidirectional silicon controlled rectifier is connected with one end of the filter capacitor, and the other end is connected with the other end of the filter capacitor through the discharge resistor; and the voltage detection circuit is used for detecting the AC voltage and outputting a detection signal to the main control circuit, and the main control circuit controls the on-off of the switching circuit according to the received detection signal. According to the low-power-consumption circuit and the refrigerator provided by the utility model, when alternating current is normally supplied, the discharge resistor does not generate power consumption; when the alternating current is cut off, the discharge resistor discharges through the optocoupler bidirectional silicon controlled rectifier, and the technical problem of high power consumption of the discharge resistor during normal power supply in the prior art is solved.

The invention provides a power line damage protection device, which comprises a power supply connecting plug, a power line and a power line damage protection unit, and is characterized in that the power supply connecting plug comprises a shell, a tripping mechanism, a live wire insertion piece, a zero line insertion piece, a grounding insertion piece and a circuit board; the power line damage protection unit comprises a tripping mechanism driving circuit and an electric leakage detection circuit. The power line comprises a live wire core wire, a zero wire core wire, a ground wire core wire, an insulating layer, an insulating sheath and an electric leakage detection layer, and the insulating layer of the live wire core wire and the insulating layer of the zero wire core wire are coated with the electric leakage detection layer; when the electric leakage detection layer breaks down, current triggers a silicon controlled rectifier Q1 in the tripping mechanism driving circuit to be conducted through the electric leakage detection layer and drives a tripping mechanism in the power supply connecting plug to cut off electric connection between a power supply and a load in time, so that electricity utilization safety is ensured, and the fire risk is reduced.

The invention relates to the technical field of power system protection, in particular to an underground power distribution network single-phase grounding protection system and method based on a signal injection method. The system comprises a signal acquisition module, a measurement and control protection module and an online monitoring module. According to the invention, by injecting the independent direct current signal and combining a zero-sequence fundamental wave time sequence identification algorithm and a traveling wave distance measurement method, rapid detection, high-precision positioning and selective protection of the single-phase earth fault of the underground low-voltage power distribution network are realized, and the method is suitable for complex environments such as coal mines and metal mines; through insulation value on-line monitoring and electric leakage protection, the ground insulation value level of a line is reflected to the voltage change of an additional direct current signal and a reactor neutral point. A zero-sequence fundamental wave time sequence identification model is adopted for electric leakage fault judgment so as to judge the fault type. By outputting a relay signal, on-off control is performed on a protected branch, so that a fault line can be quickly cut off when a fault occurs, and equipment and a bus are protected from being damaged by the fault.

The invention provides a method for setting a relationship between conduction voltage drop and junction temperature of a power device in a large-current on-off state, and the method enables a tested device to work in the on-off state, and the large current flowing through the device is a square wave current with a fixed amplitude and a fixed duty ratio. The operation junction temperature and the reference point temperature are set by controlling the operation condition of the circuit and the temperature of the radiator; after the device runs to a thermal steady state, measuring the conduction voltage drop and the reference point temperature of the device, then cutting off a large current, and injecting a constant small current into the measured device to measure the junction temperature of the measured device; the equivalent temperature of the packaging material is represented by the reference point temperature, and a linear relation among the conduction voltage drop, the reference point temperature and the junction temperature under the large current is fitted. According to the invention, the self-heating and external heating conditions of the whole timer can be flexibly controlled, and the influence of the temperature of the packaging material on the conduction voltage drop is considered, so that the accuracy of predicting the junction temperature by using the conduction voltage drop under large current is improved.

The invention provides a gate driving device and a display panel, and relates to the technical field of display driving. The gate driving device comprises a cascade transmission circuit, a first frequency dividing circuit and a first output circuit. Wherein the cascade transmission circuit is connected with a first node and used for controlling the potential of the first node according to a cascade transmission signal, and the first frequency dividing circuit is used for controlling the potential of a second node according to the potential of the first node and a first frequency dividing signal transmitted by a first frequency dividing line; the first output circuit comprises a sixth transistor; and when the first node is in a low level state, the potential of the second node is maintained above a preset threshold voltage, so that the sixth transistor is cut off or conducted in a linear region. When frequency division switching needs to be carried out, even if the second node is in a passive high-level state, and the first node is in a low-level state, the potential of the second node is maintained above a preset threshold voltage, so that the sixth transistor is cut off or conducted in a linear region, and display abnormity caused by output abnormity of a first gate driving signal during frequency division switching is avoided.

The utility model belongs to the technical field of leakage protectors, and particularly relates to an alternating current screen leakage protection circuit and device, and the circuit comprises a power management circuit which comprises a molded case switch and is used for the on-off of the current of an electrical load; and the breaking control circuit is connected with the power supply management circuit. According to the utility model, through cooperation of the power management circuit, the breaking control circuit, the electric leakage monitoring circuit and the connection control circuit, a setting value can be adjusted according to characteristics of an actual electrical load, an electric leakage current in an electrical load loop can be monitored in real time, and once it is monitored that the electric leakage current exceeds a preset setting value, the electric leakage current is monitored to be abnormal. The power supply can be quickly and automatically cut off to prevent electric shock, fire and other dangerous situations caused by electric leakage, the problem that traditional equipment is insensitive to small current leakage is effectively solved, the use flexibility is improved, and meanwhile, the safety and efficiency of electrical load equipment are remarkably improved.

The invention discloses a protection method for a low-voltage power grid, the low-voltage power grid comprises a transformer area intelligent terminal and a plurality of intelligent switches, the transformer area intelligent terminal and the plurality of intelligent switches are connected through power lines, and the method comprises the following steps: establishing a longitudinal communication network between the transformer area intelligent terminal and the plurality of intelligent switches; determining a branch level of the low-voltage power grid according to the voltage, the current, the power, the electric energy and the alternating-current zero crossing point; drawing an electrical topological relation of the plurality of intelligent switches based on the branch hierarchy; establishing a transverse communication network of the plurality of intelligent switches based on the electrical topological relation; and when the power line has a short circuit or a grounding fault, the fault area is cut off through the corresponding intelligent switch, the fault information is broadcasted and the fault area is positioned through the transverse communication network, and the fault information is reported to the station area intelligent terminal through the longitudinal communication network. According to the protection method, the fault area can be accurately positioned, so that the emergency situation of the low-voltage power grid can be efficiently and quickly handled in real time.

The railway safety equipment comprises a redundant power supply circuit, a power distributor, a controller and a main circuit, the output end of the power distributor is connected to the controller and the main circuit, and the input end of the power distributor is connected to the redundant power supply circuit; the redundant power supply circuit comprises a power output terminal, a first gated field effect transistor, a pull-down resistor, a first P-channel field effect transistor, a second P-channel field effect transistor, a third P-channel field effect transistor and a voltage division circuit, and a second diode is connected in parallel between the drain electrode and the source electrode of the second P-channel field effect transistor. And the positive electrode of the second diode is connected with the drain electrode of the second P-channel field effect transistor. Compared with the prior art, the invention can prevent reverse flow into the main power supply interface to break down other electric equipment when the standby power supply supplies power, and can improve the switching speed while quickly cutting off the standby circuit after the main power supply is conducted.

The invention discloses a virtual reactive power plant user single-phase asynchronous motor reactive power regulation method, and relates to the technical field of electrical equipment control, and the method comprises the steps: collecting the real-time state data of a key node of a power distribution network, and building a short-term prediction model based on the state data; setting a judgment condition according to a prediction result of the model, generating a preliminary reactive power regulation instruction, and adjusting the priority and the regulation amplitude of the preliminary reactive power regulation instruction in real time based on dynamic updating of a prediction trend; issuing the adjusted reactive power adjustment instruction to a user terminal, and performing cooperative processing based on distributed coordination control to generate a final cooperative adjustment instruction; executing an action of cutting off the split-phase capacitor of the single-phase asynchronous motor according to the coordinated adjustment instruction; according to the invention, the split-phase capacitance of the single-phase asynchronous motor at the user side is regulated and controlled by using the virtual reactive power plant, so that low-cost, quick-response, continuous and accurate reactive power regulation is realized, and the problems of reactive power excess and high voltage of a power grid are effectively solved.

The invention relates to the technical field of charging pile control, and discloses a charging control method for a wall-mounted shared charging pile, and the method comprises the steps: providing electric energy for to-be-charged equipment under charging parameters; collecting charging data of each charging pile according to a first collection period; whether an abnormal charging pile exists or not is judged, and a first collection period of charging data of the abnormal charging pile or charging parameters are adjusted according to the abnormal proportion; the predicted charging data comprises predicted voltage and predicted current; and whether the charging process is abnormal or not is determined through the predicted charging data and the next abnormal charging data, early warning is given out based on the judgment result of charging abnormity, and charging output of the abnormal charging pile is cut off. According to the method, the safety and the stability of the charging process are remarkably improved, the energy consumption is reduced through an intelligent dynamic adjustment strategy, and the reliability of the shared charging service and the user experience are greatly improved.