63 results about "Ground failure" patented technology

The invention belongs to the technical field of ground fault test pull line selection and section selection, and particularly relates to a ground fault test pull line selection and section selection method. The method comprises the following steps: performing grounding fault starting judgment according to a grounding signal or a bus phase voltage; after grounding fault judgment is started, fault type judgment is carried out, and the fault types comprise a permanent fault and a transient fault; if the fault is judged to be a permanent fault, a comprehensive line selection and section selection strategy is adopted, and an optimal fault line selection and section selection result is output; based on a fault line selection and section selection result, further positioning a grounding fault interval through a test pull strategy; and after the grounding fault interval is determined, rear-end load transfer is started, and load side power supply is recovered. According to the method, through a multi-criterion fusion starting and comprehensive line selection strategy, weighted comprehensive scoring of a group amplitude comparison and phase comparison method, a first half wave polarity method and a transient energy method is combined, and the limitation of a single method is effectively overcome.

The utility model discloses a ground fault active full-compensation device using an energy storage unit, which comprises a controller, an active power compensator, a boosting transformer, a full-compensation switching high-voltage switch and an energy storage unit for providing electric energy for the active power compensator and absorbing excess energy when the active power compensator is switched on and off a grid, the AC input end of the energy storage unit is connected with an AC power supply, and the positive and negative ends of the energy storage unit are respectively connected with the DC side bus positive and negative electrodes of the active power compensator. According to the utility model, the energy storage unit is arranged in the system to provide a working power supply for the active power compensator, so that the battery of the energy storage unit can be charged with lower power, and the active current, the reactive current and the harmonic current of a system fault point can be compensated with higher current, thereby reducing the power supply capacity required by the rated power work of the active power compensator; the addition of other equipment is avoided, the equipment investment is reduced, and the occupied area is saved.

A ground fault determination system includes an acquisition unit that acquires the degree of deterioration of a plurality of fuel cell stacks connected in parallel with each other and connected to an inverter, a ground fault detection unit that detects insulation resistance between the inverter and the plurality of fuel cell stacks, a first determination unit that determines, when the deterioration of each fuel cell stack has not yet progressed, whether there is a ground fault with all the fuel cell stacks all at once, and a second determination unit that determines in turn, when the deterioration of at least one fuel cell stack has progressed, whether there is a ground fault with each fuel cell stack.

The invention relates to an initiating explosive device grounding state monitoring device and method, and belongs to the technical field of initiating explosive device safety monitoring, and the device comprises N * M measurement and control combinations, N sets of measurement and control combinations and a set of main control computer, the measurement and control combination and the arrangement in a dangerous area for storing the initiating explosive devices adopt explosion-proof design, and the main control computer is arranged in a management area outside the dangerous area without adopting the explosion-proof design; each set of measurement and control combination is connected with M sets of measurement and control combinations, and the N sets of measurement and control combinations are connected to the main control computer; connecting the initiating explosive device to the corresponding measurement and control combination; the measurement and control combination obtains an in-place state by performing in-place monitoring on the initiating explosive device, and performs a grounding resistance test on the in-place initiating explosive device to obtain a grounding state signal; and the main control computer manages and controls the N sets of measurement and control combinations, receives and displays the in-place and grounding states of the initiating explosive device, judges a grounding fault and gives an alarm. The initiating explosive device safety management system has remarkable advantages in the aspect of improving the efficiency and safety of initiating explosive device safety management.

To provide a ground fault detection device, a ground fault monitoring device, and a ground fault monitoring system capable of stably detecting both ground faults caused by lightning strikes and ground faults caused by contact with flying objects such as birds and animals.SOLUTION: A ground fault detection device installed on a tower leg of a power transmission tower 2 and for detecting ground faults includes: a ground-fault current detection unit 12, 14 that outputs an activation signal triggered by current flowing through the tower leg; magnetic sensors 16 and 17 that measure magnetic flux density due to ground fault current; and a control unit 15 that causes the magnetic sensors 16 and 17 to measure the magnetic flux density due to the ground fault current when the activation signal is received from the ground-fault current detection unit 12, 14.SELECTED DRAWING: Figure 1

The invention provides a mobile electric ground wire installation vehicle, and relates to the technical field of electric power overhaul, the mobile electric ground wire installation vehicle comprises a mobile carrier unit, a multi-section telescopic insulation lifting mechanism, a multi-dimensional adjusting mechanism, a ground wire clamp, a sensing module, a core electric control unit and a man-machine interaction unit, the mobile carrier unit is used for realizing full-area movement and positioning of the device; the multi-section telescopic insulating lifting mechanism is connected to the mobile carrier unit and is used for driving the grounding wire clamp to lift to a target height; remote operation can be achieved through the man-machine interaction unit, and the problem that the visual field is blocked in traditional manual operation is thoroughly solved; the sensing module can monitor the meshing state of the grounding wire clamp and the wire in real time, identify abnormal conditions such as virtual connection in time, and avoid the risk of grounding failure. The obstacle avoidance function of the mobile carrier unit and the protection mechanism of the power supply can effectively prevent equipment collision and circuit faults, and eliminate personal potential safety hazards from multiple dimensions.

The utility model belongs to the technical field of power distribution network grounding protection, and discloses a grounding protection device for a power distribution network, which comprises a grounding electrode, a protective shell and a soil humidity adjusting mechanism, the grounding electrode is detachably arranged in the protective shell, the protective shell is provided with a plurality of through holes, and the soil humidity adjusting mechanism is arranged in the protective shell. The soil humidity adjusting mechanism comprises a water storage tank, the lower end of the water storage tank is communicated with a water outlet pipe, a water valve is installed on the water outlet pipe, and a water outlet of the water valve is communicated with the interior of the protective shell through a connecting hose. Therefore, the reliability of the grounding effect is improved, and the problem of grounding failure caused by too low soil humidity is avoided.

The application relates to the technical field of relay protection, in particular to a fault phase selection method for a wind farm sending-out line based on transient waveform-energy multi-feature fusion and application thereof. Wavelet energy of each-phase current fault component is used as a horizontal axis, and a fractal dimension thereof is used as a vertical axis, so that a two-dimensional plane with two types of minimum enclosing circles is formed; a fault sample is projected onto the two-dimensional plane; and a distance between the fault sample and a two-class minimum enclosing circle region on the two-dimensional plane is used as a fault phase selection criterion; and the fault phase selection is performed when a ground fault is excluded according to the size of zero-mode voltage. The required time window is short, and the problem that fault phase selection is inaccurate when a far-end high resistance is identified by a traditional phase selection method is overcome. The application aims to solve the problem of how to perform fast and accurate fault phase selection for a wind farm sending-out line without relying on power frequency quantities.

The invention relates to a variable-speed pumped storage unit stator grounding and rotor grounding fault arc extinction method and device based on machine end injection. The method comprises the following steps: acquiring and determining a phase corresponding to a minimum actual voltage in three phases of the variable-speed pumped storage unit as a fault phase under the condition that a ground fault of the variable-speed pumped storage unit is monitored, and acquiring a first electric signal under the condition that the ground fault is a stator ground fault; according to the first electric signal, a first arc extinction compensation amount is determined, and the first arc extinction compensation amount is injected into a stator winding from the machine end of the variable-speed pumped storage unit, so that effective arc extinction of a stator grounding fault is achieved; and when the grounding fault is the rotor grounding fault, acquiring an injection signal and a second electric signal, then determining a second arc extinction compensation amount according to the injection signal, the fault phase and the second electric signal, and injecting the second arc extinction compensation amount to the rotor winding from the machine end of the variable-speed pumped storage unit so as to realize effective arc extinction of the rotor grounding fault.

The present invention provides a grounding fault grading detection and location system applicable to monorail vehicles. The fault detection unit includes: a voltage sensor disposed between the negative busbar and the vehicle body for detecting the voltage V between the negative busbar and the vehicle body; a data acquisition unit for acquiring the voltage value detected by the voltage sensor, and a fault analysis unit for analyzing and locating the grounding fault of the monorail vehicle according to the voltage value acquired by the data acquisition unit: if V2 < V ≤ V3, the fault occurs between the train AC380V system and the vehicle body, or between the AC220V system and the vehicle body; if V1 < V < V2, the fault occurs between the DC110V system and the vehicle body. Further, by combining the current values detected by the pantograph current sensor, the auxiliary power supply box current sensor, and the traction inverter box current sensor, the location of the grounding fault is determined. This system automatically locks the system and equipment where the grounding fault occurs by adding some on-vehicle voltage and current sensors on the train and comparing and analyzing the acquired voltage and current values.

The invention relates, among other things, to a test device.According to the invention, the test device (TE1, TE2, TE101-TE104, TE201-TE202) comprises: a first feed-in device (E1v, E1f) for applying a first coded test signal (T1v, T1f) between a first terminal (A1v, A1f) and a reference terminal, a first measuring device (M1v, M1f) suitable for measuring a first measurement signal (MS1v, MS1f) that is at least partially caused by the first coded test signal and influenced by any ground fault in a connecting line connected to the first terminal, and a first evaluation device (AUS1v, AUS1f) that subjects the first measurement signal and the test signal to a first correlation check, generating a first correlation signal, and, in the event of a change in the amplitude of the first correlation signal beyond a predetermined correlation-related measure, concludes that there is a ground fault and a first Error signal (F1v, F1f) generated.

To accurately pinpoint the fault location and detect ground fault accidents early. [Solution] An information processing device having a processor and a memory device acquires fault information from a plurality of measurement terminals installed at multiple points on a power distribution line, including a first current value which is the current value of the surge current when the power distribution line has a ground fault, and a second current value obtained based on the first current value and having an amplitude smaller than the amplitude of the first current value. When the amplitude of the first current value is greater than or equal to a predetermined threshold, the time when the second current value first reaches its peak value is determined for each of the multiple measurement terminals as the surge arrival time when the surge current reaches the plurality of measurement terminals, and the ground fault point where the ground fault occurred is determined based on the difference in the surge arrival times between adjacent points.

The embodiment of the invention provides a ground fault identification method, system and device of a power system and a storage medium, and belongs to the field of power system protection and control. The method comprises the steps of receiving a fault record file sent by a power distribution terminal; obtaining a zero-sequence current waveform according to the fault record file; performing local feature extraction on the zero-sequence current waveform to obtain fault feature data; inputting the fault feature data into a preset long and short term memory classification model to obtain fault probabilities of a plurality of preset grounding fault cause categories; the multiple grounding fault cause categories comprise an external force wire breaking category, an insulation damage category and a foreign matter wire lapping category; and according to the fault probability of each grounding fault reason category, determining a grounding fault target reason and outputting the grounding fault target reason. According to the embodiment of the invention, the reason causing the grounding fault can be identified.

The invention discloses a grounding fault positioning device for a 35KV line. The grounding fault positioning device comprises a host and a fault positioning module, the host is used for generating a test signal and injecting the test signal into a fault line to be tested; and the fault positioning module is used for receiving a reflection signal returned by the fault line based on the test signal, and performing fault positioning according to the reflection signal to determine a fault point. Through cooperative work of the host and the fault positioning module, the host generates a test signal and injects the test signal into a to-be-detected fault line, more effective detection can be carried out for different types of grounding faults, the fault positioning module can rapidly receive a reflected signal and carry out fault positioning, the position of a fault point is determined in time, and the fault detection efficiency is improved. And operation and maintenance personnel can quickly take measures for maintenance according to the positioning result, so that the fault processing time is shortened, the power failure time is reduced, and the power supply reliability of the power system is improved.

The invention discloses a ground fault feature fusion recognition processing method, system and device and a medium, and belongs to the technical field of power distribution network relay protection, and the method comprises the steps: collecting current data, and judging whether a ground fault exists or not based on the current data; if the grounding fault exists, extracting a first parameter and a second parameter generated by the fault, and setting a corresponding threshold value; dividing the grounding fault into an instantaneous grounding fault or a permanent grounding fault according to the first threshold value, the second threshold value, the current data and corresponding judgment conditions; a first closed-loop control or a second closed-loop control is performed for the instantaneous ground fault or the permanent ground fault. According to the method, the problems of high misjudgment rate and inaccurate processing of the grounding fault of the power distribution network caused by dependence on a single fault feature in the prior art are solved, and particularly under the conditions of distributed power supply access and high-resistance grounding, the fault identification precision and the processing reliability are improved, and instantaneous and permanent faults are distinguished and properly processed.

A ground fault detection system for a power system having a DC link, a battery bank, a link capacitor unit connected to the DC link, and plural power converters connected to the DC link. The power converters convert first DC power from the DC link to at least one of AC power or second DC power for powering at least one electrical load. A control unit disconnects the battery bank from the DC link responsive to detection of a ground fault, to deactivate operation of the power converters, and to sequentially at least partially activate, with power from the link capacitor unit, each of the power converters individually until a sensed voltage signal of the DC link is indicative of the ground fault being associated with one of the power converters.

The invention discloses a green grounding method and system for a new energy station. The method comprises the steps of obtaining multi-source grounding parameters such as soil resistivity, station topology, meteorological data and a fault current predicted value; a grounding grid optimization configuration parameter is generated through a dynamic weighted fusion algorithm; constructing a self-adaptive grounding grid structure comprising an adjustable grounding electrode depth module and a variable topology connection module; monitoring the state of the grounding grid in real time and dynamically adjusting; when a ground fault is detected, a green arc extinguishing strategy is started, and the pre-embedded energy storage element and the power electronic device are utilized to actively guide and extinguish the arc. According to the invention, the problems of poor environmental adaptability and poor fault arc extinction effect of the grounding system of the new energy station are solved, and the reliability, safety and intelligent level of the grounding system are significantly improved through dynamic adaptive adjustment and an active arc extinction strategy.

The invention discloses an active prevention and control system for sand foundation damage under the earthquake action and a construction method of the active prevention and control system. The system comprises a main body structure pressed into a sand stratum, earthquake frequency obtaining units annularly distributed on the periphery of the main body structure and a power supply unit on the top. The main body structure comprises an analysis feedback unit, an execution unit and a reinforcement unit, the analysis feedback unit receives seismic frequency data and generates an anti-phase waveform instruction, and the execution unit vibrates to weaken the seismic action; and under the high-strength earthquake working condition, the earthquake load effect rises, the pore water pressure rises to the preset threshold value, the reinforcing units are triggered, the reinforcing grout flows out of the honeycomb grid-shaped side wall, and grouting reinforcement of the foundation is achieved. The construction method comprises the steps of site exploration, drilling operation, unit layout, structure lowering, connection debugging and effect detection. By means of the principle of interference reduction, through the synergistic effect of active vibration reduction and instant reinforcement, full-stage prevention and control of sand liquefaction are achieved, the response speed is high, and the reinforcement effect can be achieved to the maximum extent.

The utility model relates to the technical field of battery bonding, and particularly discloses a shell, a battery pack and a bonding structure. The outer lining is installed on the shell body, and the material of the outer lining is the same as that of the shell body; wherein the external lining is provided with an accommodating cavity; the inner lining is fixedly mounted in the accommodating cavity and is used for being connected with a ground bonding fastener in a fastening manner; wherein the grounding fastener is used for fixing a grounding part on the shell, so that the grounding part is electrically connected to the shell body. According to the shell, the battery pack and the grounding structure provided by the utility model, the problem that the grounding failure is easily caused by galvanic corrosion of the existing grounding structure can be effectively solved.

A ground fault in a vehicle drive unit comprising an inverter is detected. The input side of the inverter is connected to a floating DC supply voltage and is controlled by a control device 12. The con

The invention relates to the technical field of power system relay protection, in particular to a ground fault distance protection method based on zero-sequence direction and angle adjustment, and the method comprises the steps: obtaining a three-phase voltage and a three-phase current, and determining a zero-sequence direction; and if the zero-sequence direction is a positive direction and the phase comparison angle of the distance relay is within a first angle range, or if the zero-sequence direction is a negative direction and the phase comparison angle of the distance relay is within a second angle range, determining that the distance relay is in an action state. And if the zero-sequence direction is a positive direction, and the distance relay is in an action state, the zero-sequence reactance relay is in an action state, and the load relay is in an action state, or if the zero-sequence direction is a negative direction, and the distance relay is in an action state, and the zero-sequence reactance relay is in an action state, executing a distance protection action. According to the invention, when the line has the grounding fault through the transition resistor, the distance protection action is executed, the fault is removed, and the stability of power grid operation is improved.

The application discloses a kind of distribution line ground fault detection device, it is related to distribution line fault detection technical field, including telescopic part, extension pipe, suspension assembly, calliper receiver, telescopic part includes central section and multiple telescopic sections, bottom of outermost telescopic section is provided with bottom disc, the top of central section is provided with connecting frame, connecting frame is provided with winding drum, and the winding drum is wound with pull rope, the top of central section is provided with guide cylinder, and pull rope passes through guide cylinder and is connected with bottom disc;Telescopic section and the outside of central section are provided with L-shaped slot, and the inside of telescopic section is provided with cooperation ball, and cooperation ball and inside corresponding L-shaped slot are mutually matched;By telescopic part, suspension assembly and calliper receiver are sent to distribution line part, and meanwhile, telescopic part is controlled to be shortened again, so that detection device realizes remote control self-inspection, and the influence of field terrain environment on inspection efficiency is avoided.

The invention relates to the technical field of power distribution networks, and provides a grounding fault diagnosis device for a power distribution network, which comprises a square block, a hollow rod is movably embedded in the square block, a slender rod is fixedly mounted on one side of the square block, and a sliding block movably sleeves the outer surface of the slender rod. One side of the sliding block is rotationally connected with a plurality of upper semicircular blocks through rotating rods, and one sides of the upper semicircular blocks are rotationally connected with hollow blocks through rotating rods. In the embodiment of the invention, an electric push rod is started through an external power supply, the electric push rod drives a movable plate to move downwards, and a motor drives the rotating rods to rotate; the rotating rod drives the ground drilling rod to rotate, at the moment, the ground drilling rod rotates while moving downwards and can drill into the ground and make contact with a grounded wire, at the moment, fault detection is conducted on the grounded wire through the fault detector, and data are transmitted to the interior of the fault detector through the data line. It needs to be explained that the length of the telescopic rod can be determined according to actual conditions.

The application relates to a variable-speed pumped storage unit stator ground fault and rotor ground fault arc extinguishing method and device based on machine end injection. In the case that a variable-speed pumped storage unit ground fault is monitored, the minimum actual voltage corresponding to the phase of the three phases of the variable-speed pumped storage unit is determined as a fault phase, a first electric signal is obtained in the case that the ground fault is a stator ground fault; then, according to the first electric signal, a first arc extinguishing compensation amount is determined, the first arc extinguishing compensation amount is injected from the machine end of the variable-speed pumped storage unit to the stator winding, so that effective arc extinguishing of the stator ground fault is realized; in the case that the ground fault is a rotor ground fault, an injection signal and a second electric signal are obtained, then, according to the injection signal, the fault phase and the second electric signal, a second arc extinguishing compensation amount is determined, the second arc extinguishing compensation amount is injected from the machine end of the variable-speed pumped storage unit to the rotor winding, so that effective arc extinguishing of the rotor ground fault is realized.

The invention relates to a line selection control method and device for a single-phase earth fault feeder, equipment and a medium. The method comprises the following steps: calculating and determining a fault feeder characteristic current of each feeder to be detected and a non-fault feeder characteristic current of a non-fault feeder; calculating and determining a third difference value between the zero-sequence current after the fault of the to-be-detected feeder line and the fault feeder line characteristic current of the to-be-detected feeder line so as to determine the final zero-sequence current of the to-be-detected feeder line, and calculating and determining a fourth difference value between the zero-sequence current after the fault of the non-fault feeder line and the non-fault feeder line characteristic current of the non-fault feeder line so as to determine the final zero-sequence current of the to-be-detected feeder line. And detecting whether a difference value between the phase of the final zero-sequence current of the to-be-detected feeder and the phase of the final zero-sequence current of the non-fault feeder reaches a preset phase angle difference threshold value or not, and if so, determining the to-be-detected feeder as a fault feeder. According to the invention, the inherent unbalanced interference of the feeder line is stripped, so that the high-resistance grounding fault line selection problem is effectively solved.

This utility model belongs to the field of power maintenance technology, specifically a grounding wire clamp for substation operation and maintenance, including an insulating rod; a U-shaped rod is fixedly connected to the top of the insulating rod; a sliding groove is formed in the middle of the insulating rod; a limit rod is rotatably connected to the middle of the sliding groove via a torsion spring; a connecting rod is rotatably connected to the end of the limit rod away from the sliding groove; the other end of the connecting rod is slidably connected to the middle of the sliding groove; a groove is formed at the end of the U-shaped rod away from the insulating rod; a connecting assembly is installed inside the end of the connecting rod connected to the limit rod; the connecting assembly includes a pull rope; a through groove is formed at the end of the connecting rod located in the middle of the sliding groove; with the above structure, when grounding outdoor power lines, the occurrence of grounding failure due to the power line shaking off the device caused by wind vibration can be reduced, thus improving the safety of the device.

The invention provides a method, a control unit and an energy storage system for locating a ground fault. Disclosed herein is a method (100) for locating a ground fault in an energy storage system (20) comprising a plurality of strings (21) in parallel. The string includes a plurality of energy storage cells (22) connected in series, and the energy storage cells include one or more energy storage modules (24), and a bypass circuit (26). The method comprises: for each string of the energy storage system, identifying (110) an energy storage cell candidate (122) as a potential ground fault location based on a number of energy storage cells (116) in the string, a pole imbalance voltage (112), and an energy storage system voltage (114); and determining (120) in which string a ground fault is located by successively bypassing at least some of the identified energy storage cell candidates in a string at a time and identifying a string measured to have a deviation from the predicted behavior.