61results about How to "Avoid widespread power outages" patented technology

The invention relates to a safety and stability control system modeling method in power system dynamic simulation. The method comprises the following steps of: performing hierarchical modeling on the safety and stability control system in a hierarchical decomposition mode; simulating an operation mode, fault information and a control strategy by adopting a ladder logic diagram to obtain a main station model and a sub-station model; and connecting a safety and stability control system model and a primary system model to realize the close-loop dynamic simulation of a large-scale power system which contains the safety and stability control system model. By the method, various different action behaviors and control characteristics of the safety and stability control system in the large-scale power system can be simulated accurately; the defects that conventional simulation software cannot reflect the action behaviors of the safety and stability control system are overcome; postmortem analysis of complex and severe accidents can be performed; and the requirements of the large-scale power system dynamic simulation on the simulation of the safety and stability control system can be met.

The invention discloses a typical daily load characteristic-based power load forecasting method, including: collecting power load data of users in a set industry in a set area, and performing preprocessing on the data; obtaining typical daily load curves of the users and an industry overall load curve; obtaining a correlation coefficient of the typical daily load curves of the users; classifying the users according to a power utilization laws of the users; and selecting a user whose power load change trend has the highest consistency with an industry overall load change, and forecasting power load data of an overall industry through the power utilization behavior laws of the user. The typical daily load characteristic-based power load forecasting method provided by the invention has the beneficial effects of being capable of deriving a forecast of an abnormality of a specific industry and even a whole society power load abnormality from an abnormality of a certain user power load, improving accuracy of a power load forecasting result, and providing a power guarantee for reasonable economic dispatching of an electric power system, reduction of production cost, and prevention of a large-area power failure of a power grid or a power grid breakdown.

The invention discloses a correlation coefficient-based industry electricity consumption law forecasting method, and includes: collecting electricity consumption data of users in a set industry in a set area; forming an electricity consumption historical data sequence and performing normalization; obtaining correlation coefficients of electricity consumption of the users and industry overall electricity consumption, and determining a correlation characteristic between an electricity consumption change of the users and an industry overall electricity consumption law; and selecting a user whose power load change trend has the highest consistency with an industry overall load change, and forecasting the electricity consumption data change law of an overall industry. The correlation coefficient-based industry electricity consumption law forecasting method provided by the invention has the beneficial effects of being callable of deriving a forecast of an abnormality of a specific industry and even a whole society power load abnormality from an abnormality of a certain user power load, improving accuracy of a power load forecasting result, and providing a power guarantee for reasonable economic dispatching of an electric power system, reduction of production cost, and prevention of a large-area power failure of a power grid or a power grid breakdown.

The invention discloses a remote intelligent residual current monitoring and protection system, which comprises a three-phase residual current protection device, single-phase residual current protection devices, a detection data / control signal transmitting device, a monitoring centre and a monitoring unit, wherein the three-phase residual current protection device is arranged on a three-phase main power line outlet; the single-phase residual current protection devices are arranged on three phases of power supply lines respectively; the monitoring unit is connected with the monitoring centre and also connected with a first stage of residual current protection device; the monitoring centre determines the upper limit value of split-phase / single-phase residual current of each phase of power supply circuit and monitors / analyzes the related detection data of a next stage of residual current protection device in real time; when the residual current on a certain phase of line exceeds the upper limit value, an alarm is sent; the amplitude of the residual current of each phase of line is monitored and adjusted to ensure the balance of the three-phase residual current; and the current of the neutral earth line of a power transformer is reduced and frequent tripping of the first stage of residual current protection device is prevented, so that the operating ratio and the reliability of the power grid are improved.

The invention discloses a power grid planning method based on a multi-core grid construction mode. The method comprises the following steps of acquiring the current power grid situation and planning boundary conditions, dividing core power grids, making the grid construction scheme of each core power grid, determining the interconnection mode among the core power grids, carrying out electrical check and analysis, making an implementation scheme of each stage and investment estimation, and outputting a target grid structure planning scheme. Through leading loads and power supplies to develop harmonically, self-balanced core power grids and the backbone grid structures are formed gradually, connection among the core power grids is simplified gradually and weakened, the target grid structure forms the structure with the core power grids as the basic units finally, each core power grid can basically realize self balancing in actual running, and the core power grids are independent relatively and can support each other. Differential planning is carried out on connection among the core power grids, the planned target grid structure has the advantages that the structure is simple and risks are dispersed, local grids can be abandoned to save the entire grid in the case of severe failure, and large-area blackout can be effectively avoided.

The invention provides a feeder terminal and line protection device, and the device comprises a power module which is connected with a dual-core heterogeneous processor and is used for supplying powerto the dual-core heterogeneous processor; a mutual inductor which is installed on a power distribution network line and collects analog quantity of line operation parameters, wherein the AD collection module converts the analog quantity of the operation parameters into digital quantity; the dual-core heterogeneous processor which analyzes and calculates the operation parameters of the received line to obtain the data of the line, judges whether the line has a fault or not, and sends a switching-off action command signal to the circuit breaker through the data transmission module if the line has the fault, so as to control the circuit breaker to disconnect the faulted line; and a wireless communication module which sends the operation parameters acquired by the dual-core heterogeneous processor, the calculation line data and the judged fault line to a cloud service platform and a user terminal. The distribution network automatic control device combining the high-speed sampling chip andthe high-speed processor control chip is adopted, so the device can complete the protection and monitoring of a distribution network line rapidly and stably.

The invention provides an online fault monitoring method for a lightning arrester. The method comprises the following steps of: receiving report information which at least comprises a voltage value and / or a current value and is sent by one or more feeder terminals through a wireless communication module in real time, calculating a difference value between the voltage value or the current value anda preset voltage value or a preset current value, and determining whether the difference value exceeds a preset error range or not; and if the difference value exceeds the preset error range, determining that lightning arresters where the feeder terminals corresponding to the reported information are located fail. The remote monitoring platform is used for monitoring the fault condition of each lightning arrester in real time; once a fault occurs, the faults of the lightning arresters can be quickly determined and the positions of the faulted lightning arresters can be positioned, maintenancepersonnel can quickly maintain the lightning arrester, time for troubleshooting fault points one by one due to faults of the lightning arrester in the prior art is greatly saved, the fault lightningarrester can be quickly replaced, a transformer or a line can be prevented from being struck by lightning to the maximum extent, and possible large-area power failure can also be avoided.

The invention discloses a method for identifying and optimizing a fragile line of an electric-gas coupling system. The method includes inputting original data, establishing an electric-gas coupling system optimization model, and processing to obtain initial operation state of coupling system; turning off the output power of each gas source of the natural gas network, calculating the gas source vulnerability, and carrying out weight processing to obtain a line coupling vulnerability factor; extracting a topological structure of the electric network and processing to obtain a line topological vulnerability factor; respectively disconnecting each power grid line to obtain a power flow distribution entropy so as to obtain a line operation vulnerability factor; comprehensively obtaining the comprehensive vulnerability of the lines, sorting according to the descending order, and the lines larger than a set threshold value are the fragile lines; and after the fragile line is identified, the transmission capacity of the fragile lines is improved through the thickened wire. According to invention, fragile line in electricity-gas coupling system can be rapidly identified, monitoring and protection of fragile line are enhanced, and probability of large-area power failure of power system can be effectively prevented.

The invention discloses a method for preventing power grid equipment from transmitting power with an earth point and a scheduling system, and belongs to the technical field of maintenance of power systems. The method comprises the steps of setting a measurement point with a fixed position at the power grid equipment; acquiring first sensing voltage data of the measurement point when the power gridequipment is in a first electrical connection state without the earth point; when the power grid equipment is in a second electrical connection state before the execution of a first power transmission step, detecting second sensing voltage data of the measurement point; if the second sensing voltage data is the same as the first sensing voltage data, executing the power transmission step, whereinthe second electrical connection state is corresponding to the first electrical connection state. The invention provides the simple and efficient equipment earthing judgement technical means for thescheduling personnel not at the maintenance site, on the one hand, the problem that the scheduling staff grasps the earth wire information by only depending on the report of the maintenance site is solved, and on the other hand, the technical blank of earthing judgment in closed equipment and at line section outside the station is filled.

The invention discloses a fragmented spare power automatic switching implementation method for multiple power incoming lines. N incoming lines refer to n incoming lines which can serve as the power incoming lines, incoming lines which can only serve as loads have no access to spare power automatic switching equipment and are not included in the n incoming lines, charging, discharging and outlet logic are automatically adjusted according to the operation mode of primary equipment, corresponding spare power automatic switching logic can be started particularly when the incoming lines are turned from the power incoming lines into load lines or from load lines into to the power incoming lines, action reliability of the spare power automatic switching equipment is improved, and the situation that because the operation mode is fixed during access according to existing spare power automatic switching technology, the spare power automatic switching equipment cannot act in certain operation modes and consequently a large-area outage is caused is avoided.

The invention discloses a silicone oil shear thickening liquid-based cable joint explosion-proof device. The silicone oil shear thickening liquid-based cable joint explosion-proof device comprises aninner protecting layer, a middle protecting layer and an outer protecting layer, wherein the inner wall of the inner protecting layer is fixedly provided with a plurality of central support units, andthe inner protecting layer is filled with silicon oil; the middle protecting layer comprises a honeycomb structure and is filled with silicon oil shear thickening liquid; the outer protecting layer is fixed onto the outer wall of the middle protecting layer in a sleeve mode and filled with silicon oil. The silicone oil shear thickening liquid-based cable joint explosion-proof device can form a certain gap from a cable joint to improve the heat dissipation rate of the cable joint; the silicon oil and the silicon oil shear thickening liquid which are filled inside the silicone oil shear thickening liquid-based cable joint explosion-proof device can avoid explosive diffusion as well as large-area power outage.

The embodiment of the invention discloses a control method and system for avoiding large-area blackout after local power network splitting, and aims at solving the technical problem that stability control after local power network splitting cannot be achieved due to the fact that a start-up dead zone exists in FCB of a traditional unit thermal power unit. The method disclosed by the embodiment of the invention comprises the steps of obtaining a fault instruction that a tie line of a regional power network and a main network is broken; carrying out splitting of the regional power network and an external power network through a preset splitting point according to the fault instruction and concertedly starting a first FCB strategy function corresponding to a unit in the split regional power network in the distance through first-level control; and if the FCB strategy function corresponding to the unit in the split regional power network is not concertedly started in the distance by the first-level control or splitting of the regional power network and the external power network cannot be carried out through the preset splitting point, splitting and starting a second FCB strategy function of a local unit in the regional power network through second-level control.

The invention relates to a fluorescent tube converter, which comprises the first converter (21), the second converter (22), and the protector (7). Wherein, one end of the first and second insulated posts (101, 102) of first and second converters has the first and second pins (201, 202), whose size and distance are matched with G13 base of standard T8 fluorescent tube; two needles of first pin (201) are connected to the power input of T5 fluorescent blast; two needles of second pin (202) are connected via wire 5; the protector (7) contains fuse; the protector replaces the starter of T8 fluorescent tube. The invention has simple operation, which can uses T5 fluorescent on former T8 fluorescent tube base.

The invention provides a protection method and device for a direct-current suspension power supply system. The method comprises the steps that the difference values of positive electrode currents andnegative electrode currents of all feed line loops of four feed lines of a traction substation are compared; if the difference value of the positive electrode current and the negative electrode current of one feed line loop of the traction substation is larger than those of the positive electrode currents and the negative electrode currents of the other free feed loops, a tripping signal is sent to the feed line loop with the largest difference value of the positive electrode current and the negative electrode current in the traction substation. According to the protection method for the direct-current suspension power supply system, when the direct-current suspension power supply system has an earthing short circuit failure, the feed line loop, supplying power to a failure point, in the traction substation is accurately judged, the tripping signal is sent to the feed line loop, and the power supply reliability of the direct-current suspension power supply system under a power supply mode is improved.

The invention relates to an MMC-HVDC black start simulation test system and a test method. The method comprises the following steps: first, disconnecting a simulation test switch to simulate power loss of one grid, and disconnecting two circuit breakers corresponding to two grids; then, charging and starting two MMCs; and finally, after the alternating voltage output by the MMC corresponding to the grid losing power is stabilized, detecting the voltage amplitude and phase of the second grid and locking the voltage phase of the second grid, and when the voltage phase of the second grid is consistent with the phase of the alternating voltage output by the second MMC, making the second circuit breaker closed and connected to the grid, thus realizing simulation test of black start. Through the test method, black start of a grid under the condition of failure can be simulated, MMC-HVDC black start can be effectively controlled, and the black start performance of a flexible DC transmission system can be studied to provide guidance for product development and engineering implementation of a converter and control protection system.

The invention discloses the technical field of micro-power grid monitoring, and particularly discloses a monitoring system and method of micro-power grid power quality. In the system, PT / CT is used for collecting voltage / current of a user in a micro-power grid, converting the voltage / current into a digital signal, and sending the digital signal to a combination unit; a relay module is used for amplifying a voltage / current signal and performing long-distance transmission; the combination unit is used for synchronizing the data sent by various PT / CT and sending the data to a micro-power grid measuring and controlling device; the micro-power grid measuring and controlling device is used for analyzing power quality and calculating power consumption and sending a result to the micro-power gridmonitoring device; the micro-power grid monitoring device is used for monitoring power quality of the user in real time, and sending a tripping instruction to the micro-power grid measuring and controlling device when a power utilization failure occurs to a user side; the micro-power grid measuring and controlling device sends the tripping instruction to the relay module, and quickly cuts off a circuit breaker corresponding to the user so as to realize quick isolation of a single user having a fault, and therefore, large-scale power failure is avoided.

The invention discloses a multiline concurrent loop closing method, which comprises the steps as follows: a main distribution network model is obtained and spliced; the spliced main distribution network model is subjected to network topology analysis; a node-branch power network model is built by determining buses as nodes and connecting equipment between the buses as branches; node voltages of the nodes are obtained; the node voltages of the nodes include node voltage phases and node voltage amplitudes of the nodes; a concurrent loop closing admittance matrix is obtained; the concurrent loop closing admittance matrix comprises a conventional node admittance matrix and a concurrent loop closing increment matrix; loop closing currents of various loop closing switches are calculated on the basis of the concurrent loop closing admittance matrix and the node voltages of the nodes; whether the loop closing currents exceed a protective limit or not is judged; and if not, the loop closing switches in the main distribution network model are simultaneously turned off. Therefore, the load transfer efficiency is greatly improved; the load transfer time is shortened; and furthermore, induction of large-area blackout is further avoided.

The invention relates to the technical field of power meter installation and power connection. The invention provides a live line connection method in a low-voltage cable branch box. The method comprises the steps of (1) preparing a device for live line connection used in the low-voltage cable branch box, wherein the device comprises a first fastening screw, a device body, a second fastening screw, and a third fastening screw, a lower portion of the second fastening screw is screwed into a second threaded hole, a lower portion of the third fastening screw is screwed into a third threaded hole,(2) preparing the low-voltage cable branch box, (3) installing the device for live line connection used in the low-voltage cable branch box to a copper strip of the low-voltage cable branch box, and(4) inserting optical line ends of a power line into a first power line insertion hole and a second power line insertion hole in a live condition when the new power line is connected and then tightening the first fastening screw and the second fastening screw with an insulating screwdriver to fix the new power line to be connected to the device body. According to the method, the live line connection operation can be carried out without a power failure.

The invention relates to an unmanned aerial vehicle intelligent inspection identification method for a power transmission tower, wherein an intelligent inspection system is adopted to inspect an insulator, and the intelligent inspection system comprises an image acquisition module carried by an unmanned aerial vehicle, a preprocessing module, a feature extraction module, a feature fusion module, a prediction judgment module and a fault reporting module. The identification method specifically comprises the following steps: 1) shooting an image of the insulator and transmitting the image to the preprocessing module; 2) performing non-local average denoising processing on the image and inputting the image into a feature extraction module; 3) adopting a neural feature extraction network to extract insulator shape features and fault features;4) carrying out feature fusion on the extracted high-dimensional features, and 5) judging the features through a prediction regression network. According to the power transmission tower insulator fault identification method, real-time identification of the power transmission tower insulator fault is rapidly and accurately achieved, and the maintenance efficiency of the insulator is improved.

The invention discloses a bird dispelling device for ultra-high-voltage power transmission equipment based on a photoelectric technology. The bird dispelling device for the ultra-high-voltage power transmission equipment based on the photoelectric technology disclosed by the invention comprises a pressing plate and a thin plate, wherein the pressing plate is fixedly connected with a clamp plate through bolts; the side wall of the pressing plate is fixedly connected with a long rod; the outer side wall of the long rod is rotatably connected with a plurality of short lantern ring rods; one end,away from the long rod, of each of the plurality of short lantern ring rods is fixedly connected with the thin plate; the side wall of the thin plate is fixedly connected with a base; and the interiorof the base is fixedly connected with a motor. According to the bird dispelling device for ultra-high-voltage power transmission equipment based on the photoelectric technology disclosed by the invention, through combination of a bull gear, a pinion gear and a circular ring gear, autorotation and revolution functions of blades can be realized; and under a condition of no wind power, the bird dispelling device also can be normally used; through functions of an illumination lamp and a storage battery, the bird dispelling effect also can be achieved at night; and through the effects of a reflective mirror and a planar mirror, a light reflection effect is realized, and the aim that the birds are dispelled so that the ultra-high-voltage power transmission equipment is protected from the birdsis achieved.

The invention provides an emergency control method and system based on branch transient power transmission capacity. According to the method and the system, the amplitude and the phase of node voltages at two ends of a branch which are easy to measure are used as information sources, a branch transient power transmission capability BTTC quantitative evaluation index is constructed, and whether anemergency control measure is taken or not is judged according to the BTTC index of the branch with the minimum BTTC index in an interconnected power grid. According to the method and the system, a wide-area measurement technology and a high-speed communication technology are fully utilized, a response-based power system wide-area safety and stability control system is constructed, real-time decision and real-time control are realized, whether transient stability exists or not can be precisely judged, and the stability level is rapidly and quantitatively evaluated; the method and the system donot depend on off-line or on-line simulation calculation, do not need to anticipate an operation mode and a fault set, are not limited to local information, can effectively avoid the risk of failure of safety and stability control measures, ensure safe and stable operation of a power system and prevent large-area power failure.

The invention discloses a leakage protector with the judgment function. According to the leakage protector with the judgment function, two circuits are arranged and correspond to slowly-varying leakage initiating current and suddenly-varying pulse leakage initiating current respectively, after one-time judgment is conducted on the suddenly-varying current caused by accidents such as large-area leakage before a delay circuit acts, and then the delay circuit acts. Therefore, the leakage protector with the judgment function effectively avoids the phenomenon that simultaneous motion of three-level leakage protectors causes large-area power failure, and is high in safety, sensitivity and rapidity.

The invention provides a bus differential protection interval CT secondary winding polarity consistency verification method, which is realized in bus protection configured in a double-bus wiring transformer substation, and a reference interval, an outgoing line interval and a bus coupler interval are formed on the bus protection. The method comprises the following steps: selecting an outgoing lineinterval as a to-be-verified interval, and disconnecting a bus coupler interval from double buses; controlling disconnectors on the reference interval and the outgoing line interval to be switched onor switched off to be conducted with the same bus; controlling a grounding disconnector connected with the reference interval to be closed, outputting primary current through a current generator to truly simulate the secondary current condition after primary equipment is loaded, and if it is detected that the bus protection large difference and the single bus small difference are both 0, determining that the polarities of CT secondary windings on the same phase of the reference interval and the outgoing line interval are consistent; otherwise, determining inconsistency. Through the method, asecondary current condition after the primary equipment is loaded is truly simulated through a primary up-flow method, and the polarity consistency of CT secondary windings at each interval of accessed bus protection is ensured.

The invention relates to a low-voltage withdrawable integrated transformer room and belongs to the field of transformer room devices of power transmission and transformation systems. The low-voltage withdrawable integrated transformer room is provided with a transformer room casing and is characterized in that a high-voltage cabinet, a transformer and a low-voltage cabinet are respectively installed at different positions of the inner cavity of the transformer room casing, the low-voltage cabinet is of a withdrawable structure and installed in a drawer unit formed by a drawer panel, drawer side plates, a drawer rear sealing plate and a drawer base plate jointly, a breaker installing plate of the low-voltage cabinet is fixed on the drawer side plates through bolts, a fixed plastic housing breaker of the low-voltage cabinet is fixedly installed on the breaker installing plate, one end of an operating rod is connected with an operating handle, the other end of the operating rod is connected with an operating mechanism of the low-voltage cabinet, the operating handle is located on the outer side of the drawer panel, the operating mechanism is directly connected with the fixed plastic housing breaker, the wire inlet end of the fixed plastic housing breaker is connected with an inlet wire insert through a primary bus, and the wire outlet end of the fixed plastic housing breaker is connected with an outlet wire insert through a primary bus.

The invention relates to a quick circuit breaker and a novel drop-out circuit breaker. The novel drop-out quick breaker comprises a base, a drop-out mechanism and a quick circuit breaker, wherein thequick circuit breaker comprises a separable conductive member structure, a pushing mechanism and a detection control module. The circuit breaker has the advantages of being simple in structure, reliable in work and capable of achieving instantaneous circuit breaking.

The invention discloses an intelligent protection control device for a power distribution network transformer and a protection method. The device comprises the transformer and a plurality of contactors connected with output circuits of the transformer respectively and correspondingly. The contactors are connected with an intelligent control instrument. The side wall of the transformer is provided with a temperature sensor connected with the intelligent control instrument. The temperature sensor is connected with an automatic switching-out mechanism. The automatic switching-out mechanism comprises a circular arc rail, and the circular arc rail is arranged on a disconnecting link board and is concentric with a disconnecting link hinge shaft. A circular arc sliding rail is arranged in the rail. One end of the circular arc sliding rail is connected with a disconnecting link insulation rod. Teeth are evenly arranged on the inner side of the circular arc sliding rail. A driving motor is arranged on the disconnecting link board. A shaft of the driving motor is sleeved with a gear matched with the teeth on the inner side of the circular arc sliding rail. A through hole through which the gear makes contact with the teeth on the inner side of the circular arc sliding rail is formed in one side of the circular arc rail. The driving motor is connected with a programmable controller of the intelligent control instrument.

The invention discloses a distribution network line ground potential checking device and method. The device comprises a microprocessor unit, a voltage unit and a current sampling unit, wherein the voltage unit and the current sampling unit are connected with the microprocessor unit. According to the method, multiple sampling tests are carried out through a sweep frequency method, whether a grounding wire exists or not is judged by judging the magnitude of current through a threshold judgment method, and a distance between a measurement point and a grounding point is calculated through an impedance method. The device is advantaged in that a grounding state of a distribution network line is confirmed from the detection technology, the hidden danger of malignant accidents caused by human factors is eliminated, reliable guarantee is provided for safe operation of power equipment and personnel safety, large-scale high-cost rectification is not needed, cost is low, a large amount of manpowerand material resources can be saved, and high economic benefits are achieved; the method can achieve quick detection and positioning, facilitates quick searching and disassembly of a grounding wire for a maintainer, shortens the line patrol time, improves maintenance efficiency of a line, and effectively prevents large-area power failure caused by a grounding accident.

The invention provides an active defense method for a key area power grid in a typhoon mode. The active defense method comprises the steps of S1, determining power flow transfer characteristics of thekey area power grid in a fault mode; S2, actively searching a prevention and control section based on the power flow transfer characteristics; S3, performing zero-cutting control on the prevention and control section searched by the key area power grid and the large power grid; S4, controlling generators and loads in the key area power grid; S5, controlling the emergency capacity of the active power of the key area power grid in advance; S6, determining the optimal opportunity of active defense; and S7, carrying out generator tripping and load shedding optimization control. According to the method, in consideration of the situation that simultaneous fault tripping of a plurality of tie lines is possibly caused in the extreme disaster climate invasion process, an active defense section search strategy is provided based on the thought of power flow pre-control, and the strategy can ensure that the impact on the key area power grid is the minimum when the plurality of tie lines break down.

A GIS bus communication pipe separating overhauling method comprises the steps that when GIS overhaul or GIS fault emergency maintenance is conducted, under the condition that multi-interval bus air chambers are communicated, buses without segmentations are separated artificially so as to avoid power interruption of a user side due to outage of the buses; corrugated pipes among bus communication pipes and connection conductors and contacts inside the bus communication pipes are demounted, and thus the corrugated pipes and buses of the corrugated pipes of the bus air chambers not in an overhaul range are additionally provided with end fittings and close covers under the condition that insulation of GIS air chambers is met; due to the fact that separation operation is conducted on the corrugated pipes among the bus communication pipes, operation of detection and separation on damaged sections caused by bus flashover is completed, and the work of the buses at normal sections is ensured. The GIS bus communication pipe separating overhauling method is applied to GIS overhaul or GIS fault emergency maintenance, the power interruption of the user side due to outage of the buses can be avoided, power failure time can be shortened, overhaul time is saved, and power supply is restored more rapidly; meanwhile, normal operation such as bus changeover can be achieved conveniently, power supply quality is ensured, and power resource cost is saved.