351 results about "Earthing system" patented technology

The invention provides a multi-dimensional electrical equipment insulation analysis and evaluation method, and relates to the technical field of electrical equipment insulation online detection and intelligent diagnosis. According to the method, an electrically isolated direct current detection channel is constructed in a neutral point small resistance grounding system, controllable direct current detection signals are injected, micro direct current leakage response signals are collected, and after zero drift correction, temperature compensation and power frequency ripple suppression are carried out, layered attribution is carried out in combination with primary system topology and an equipment ledger, and a multi-dimensional response matrix is formed. According to the method, environment and working condition normalization is realized through factor rejection and robust pull-back, a mechanism model containing leakage channel equivalent parameters and path constraints is established, multi-working-condition data is fused to calculate equivalent insulation parameters and credibility indication quantity, and a multi-dimensional insulation representation vector is generated. And performing time sequence analysis on the representation vector, extracting degradation and abrupt change characteristics, outputting a health index and a risk level, and realizing quantitative evaluation and intelligent early warning of the insulation state.

The invention particularly relates to a discharge machining simulation control system for a nuclear power plant in a high-radiation boron-containing water environment, which belongs to the technical field of special maintenance in the high-radiation environment of the nuclear power plant and comprises a man-machine interaction system, a discharge machining control system and subsystems. Each subsystem comprises a pulse power supply system, a servo power system, a washing system, a purification system, a grounding system and a tool system; the man-machine interaction system is used for man-machine interaction and displaying the discharge machining implementation data fed back by the subsystems; the electric discharge machining control system is used for generating an electric discharge machining instruction according to the man-machine interaction information and controlling the subsystems to cooperate to perform electric discharge machining work; and each subsystem is used for implementing electric discharge machining work according to the electric discharge machining instruction and feeding back electric discharge machining implementation data. According to the invention, simulation control of discharge processing in the high-radiation boron-containing water environment of the nuclear power plant is realized.

The invention discloses a power distribution network grounding fault research and judgment analysis method, relates to the technical field of power distribution network fault analysis, and solves the technical problem that fault analysis is not accurate and deep enough due to the fact that fault features in a neutral point grounding complex fault scene cannot be comprehensively considered. According to the method, single-phase grounding fault models of a neutral point ungrounded system, an arc suppression coil grounded system and a small resistor grounded system are respectively constructed, grounding current, phase voltage and neutral point voltage expressions under the models are detailedly deduced, and characteristics of voltage and current before and after a fault point in the steady-state and transient-state processes are deeply analyzed; the method comprehensively considers various complex fault scenes, can more accurately grasp essential characteristics of faults in different grounding modes, and provides a more comprehensive and accurate basis for fault diagnosis and processing.

A dynamo-electric rotary machine includes a rotor defining an axis, a stator, and a can designed for arrangement in an air gap between the rotor and the stator in order to seal the stator and the rotor in relation to each other. The can has at least one section of average electrical conductivity in a range from 1 S / m to 10000 S / m in an axial and / or a tangential direction. The can is electrically conductively incorporated in an earthing system of the dynamo-electric machine.

A method and system for measuring distribution network system parameters based on harmonic injection, for use in a low-current grounding system containing an arc suppression coil. The system injects currents of multiple frequencies into the neutral point of the low-current grounding system through an injection source and measures the neutral point voltage. The system uses formulas to calculate and obtain the line capacitance, arc suppression coil inductance, and damping resistance parameter values ​​in the distribution network system. This application can accurately measure line capacitance, arc suppression coil damping resistance, and reactance by injecting only two frequencies of current. This method has little impact on grid operation, high measurement accuracy, and broad application prospects.

The invention discloses a grounding fault judgment method and system of a distribution line grounding system, a storage medium, electronic equipment and a computer program product. According to the ground fault judgment method, the ground fault judgment system determines a zero-sequence voltage abrupt change value and a zero-sequence voltage amplitude according to the collected zero-sequence voltage of the distribution line; under the condition that the zero-sequence voltage abrupt change value meets a preset zero-sequence voltage abrupt change value condition, determining a transient grounding judgment result and a zero-sequence admittance value according to the collected zero-sequence current and zero-sequence voltage of the distribution line; determining the classification condition of the zero-sequence admittance value according to the transient grounding judgment result; under the condition that the zero-sequence voltage amplitude meets a preset zero-sequence voltage amplitude condition, determining a zero-sequence admittance judgment result according to the classification condition of the zero-sequence admittance value and the zero-sequence admittance value; determining a grounding comprehensive result according to the transient grounding judgment result and the zero-sequence admittance judgment result; and determining a grounding fault condition of the distribution line according to the grounding comprehensive result and a preset grounding result condition.

The invention discloses a full-power variable-speed pumped storage unit stator winding insulation state online monitoring method, and provides a high-capacity generator unit stator winding insulation state online monitoring method which can be applied to a network side transformer neutral point ungrounded system. According to the method, an effective common-mode monitoring loop can be established, and monitoring is carried out by utilizing the third harmonic of the motor stator winding and is not interfered by the high-frequency switch harmonic of the frequency converter. In order to solve the problem that a full-power variable-speed pumped storage unit generally has large capacity and is not easy to realize online measurement, the invention provides a method for measuring on a neutral point outgoing line, which can realize online measurement of the insulation state of a stator winding when the load current is relatively large. The method is suitable for a full-power variable-speed pumped storage high-capacity unit, leakage current measurement can be carried out under the condition of large load current, and stator insulation information online monitoring is achieved.

The utility model relates to the technical field of enterprise power grid operation and maintenance, in particular to a rapid isolation protection device for a grounding fault of a power grid neutral point ungrounded system, and aims to solve the problems that when the grounding fault of the power grid neutral point ungrounded system is processed at present, grounding is relieved by generally adopting an arc-extinguishing and resonance-eliminating mode of manually resetting a rapid switch; and a large-area power failure accident is caused by breakdown and short circuit of an insulation weak point of equipment in a system due to too long processing time. According to the device, a fault point is isolated through zero-sequence power direction protection action tripping, closing of the vacuum circuit breaker is converted into metal grounding through action of the quick switch arc-extinguishing and resonance-eliminating circuit, and quick fault isolation is effectively realized through automatic resetting and delay setting functions of the arc-extinguishing and resonance-eliminating circuit. Therefore, the repeated action of the rapid switch arc-extinguishing and resonance-eliminating circuit caused by intermittent arc grounding is avoided, the occurrence rate of large-area power failure accidents caused by arc grounding is greatly reduced, and the safe and stable operation of an enterprise power grid is further ensured.

The invention discloses a pile foundation external application device, a grounding pile foundation and a grounding system, the pile foundation external application device is cylindrical and comprises a base body layer, a transition layer and an external coating layer, the transition layer is wrapped by the external coating layer, the base body layer is wrapped by the transition layer, and the resistance of the transition layer is in index attenuation distribution from the resistivity of the base body layer to the resistivity of the external coating layer. Therefore, the substrate layer, the transition layer and the outer coating layer form a gradient conductive structure, the resistivity of the pile foundation external application device is in gradient distribution, the interface potential barrier is effectively inhibited, and the pile foundation grounding resistance is effectively reduced after the pile foundation external application device is externally applied to a grounding pile foundation, so that the grounding resistance of a grounding system is reduced, and the diversion performance of the grounding system is improved.

The invention discloses a submarine cable interlayer fault detection method and system for a submarine cable grounding system, and a medium. The method comprises the following steps: S1, pre-installing a power frequency current sensor, a power frequency voltage sensor and a traveling wave sensor on a sheath layer and an armor layer of landing sections at two sides of the high-voltage alternating-current submarine cable grounding system; the method comprises the following steps: extracting current and voltage signal data of a fault state through a power frequency current sensor, a power frequency voltage sensor and a traveling wave sensor, and carrying out data preprocessing including detection cleaning, data interpolation and data normalization on the current and voltage signal data; according to the method, fault codes are obtained through data collection, preprocessing, feature fusion, training learning and coding reconstruction and classification, and accurate fault detection is carried out on submarine cable interlayer faults through the fault codes.

The invention relates to the field of power systems, in particular to a power cable cross interconnection grounding system live-line maintenance method and system. The method comprises the following steps: firstly, synchronously acquiring cable line load current, three-phase grounding ring current and grounding resistance at the head end and the tail end of a metal sheath of a crossed interconnection unit with ring current abnormity, and generating a real-time data set with a timestamp; extracting cable structure parameters based on a preset cable topology database, and dynamically associating the cable structure parameters with the real-time data set; constructing a multi-conductor transmission line equation model, calculating a theoretical circulation distribution value of each section of sheath, and generating a theoretical circulation map; carrying out matching analysis on the theoretical circulation map and actually measured circulation data, and determining defect types and positions; and finally, according to a defect positioning result, the maintenance operation is executed in an electrified state through the insulating mechanical arm, and the stability of the grounding impedance of the system is maintained through the bypass grounding device. The problems that in the prior art, the live detection function is incomplete, and defects cannot be rapidly and accurately positioned are solved.

An enclosure to protect people and instruments from the effects of an electromagnetic pulse (EMP) is provided. The enclosure includes a floor assembly; walls extending upward on a first, second, third, and fourth side of the floor assembly; a roof; and a ceiling. On the interior of the enclosure, a shield layer is provided such that the enclosure forms a six-sided Faraday cage. Fasteners and other conductive securement materials such as copper tape help achieve the conductivity of the shield layer. Extending through the walls of the enclosure may be secure points of entry allowing for people, air, and conductors to securely enter and exit the enclosure. The enclosure contains a grounding system to assist with protecting the contents of the enclosure from the effects of the EMP.

The invention discloses a fault current calculation method and system for a high-voltage alternating-current submarine cable grounding system and a storage medium, and the method comprises the following steps: enabling a power supply device and an electric device to be equivalent to an impedance and series voltage source combination and a load impedance based on the Thevenin equivalence theorem; in combination with the double-end grounding characteristic, a submarine cable loop is equivalent according to a pi type, and a three-phase equivalent circuit is constructed; determining a fault phase, and dividing the submarine cable as a left side and a right side by a fault point; a voltage loop equation is listed based on the Kirchhoff theorem, and a matrix recursion rule is deduced in combination with a double-side elimination principle. And establishing an analytic relationship between the main sections of the submarine cables at the power side and the short-circuit side and the fault circulating current according to a recursion rule. And with a fault point current equation as a boundary condition, left sheath fault circulation distribution is solved simultaneously. And repeating the steps on the right side to obtain right side distribution so as to obtain fault phase whole-line distribution. According to the method, the circulation distribution can be accurately calculated, the fault analysis accuracy and efficiency are improved, and support is provided for submarine cable operation and maintenance and the like.

The invention discloses a grounding resistance thermal-electric coupling prediction method and system suitable for various soil scenes. The method comprises the following steps: acquiring an electrode parameter, a soil parameter, a grounding fault parameter and initial temperatures of an electrode and soil; calculating an electrode current and a soil leakage current of the time step based on the electrode and soil resistivity of the time step; based on the electrode current and the soil leakage current of the time step, calculating the electrode temperature, the soil radial temperature distribution and the grounding potential rise of the time step by adopting a finite difference method; based on the electrode temperature and soil radial temperature distribution of the time step, updating the electrode resistivity and the soil resistivity of the time step + 1; if the end of the fault time is not reached, returning to continuously calculate the temperature of the electrode and the soil at the time step + 1; otherwise, outputting the electrode temperature and soil radial temperature distribution of each time step. According to the invention, thermal-electric dynamic coupling is considered, and accurate evaluation of the performance of the grounding system is realized.

The invention belongs to the technical field of fire-fighting alarm system construction, and discloses a construction technology for a fire-fighting automatic alarm system, and the technology comprises the following steps: S1, cable laying and protection; s2, accurately positioning and installing the detector; s3, system grounding and electromagnetic protection; s4, dynamic parameter adjustment and linkage test; and S5, performing three-dimensional shape scanning and compensation correction. A stable charge release path is formed through an independent grounding system and a multi-level shielding technology, external electromagnetic interference is effectively isolated, and real-time performance and accuracy of fire alarm signal transmission are guaranteed. The spatial layout optimization of the detector is combined with a laser calibration mechanism, the influence of structural shielding and airflow disturbance on sensitivity is broken through, and millisecond-level capture and positioning of fire characteristic signals are realized. A dynamic parameter closed-loop control and multi-system linkage verification technology ensures the cooperative response efficiency of emergency equipment under extreme working conditions, and constructs a whole-process security closed loop from early warning to disposal.

The invention discloses a method and a system for diagnosing defects of a sheath grounding system under resonance voltage resistance of a power transmission cable. The method comprises the following steps: installing a sheath grounding current acquisition system; sequentially carrying out main insulation resonance voltage withstanding tests on three phases of the power transmission cable, and synchronously recording a grounding current waveform of a metal sheath by adopting a current acquisition system when each phase is subjected to voltage withstanding; processing the grounding current waveform by adopting a signal processing algorithm, and extracting a resonance component; and constructing a defect diagnosis matrix according to the resonance component, calculating a deviation between the defect diagnosis matrix and a standard matrix as a defect characterization value of the cable sheath grounding system, and obtaining a defect diagnosis conclusion of the sheath grounding system under the resonance withstand voltage of the power transmission cable. According to the method, the grounding current waveform of the metal sheath is synchronously acquired and analyzed in the main insulation resonance voltage withstand test of the three-phase cable, the resonance component is extracted, accurate identification of the defect is realized based on deviation calculation of the defect diagnosis matrix, and the detection sensitivity and the diagnosis reliability of the latent defect of the sheath grounding system before the cable is put into operation are improved.

The invention discloses a liquid oxygen rock breaking system and method, the system comprises an oxygenation system, a gas distribution system, a fracturing rock breaking pipe system, an excitation system and an electrostatic prevention and removal grounding system, a fracturing rock breaking pipe comprises a flexible outer sleeve film, an oxygenation guide pipe in the flexible outer sleeve film extends to the bottom and is filled with an adsorption combustion agent, and the top end of the flexible outer sleeve film is sealed through a hole sealing filling body. The method comprises the steps of manufacturing and installing the fracturing rock breaking pipe, sealing holes through the hole sealing filling body, laying the gas distribution pipeline and the wire, precisely injecting oxygen and synchronously exciting. Through modular integration and structural innovation, the problems that in a traditional liquid oxygen rock breaking technology, oxygenation is not uniform, pressure is unbalanced, excitation is not synchronous and the like are solved. The multi-stage gas distribution system is combined with the flow distributor to achieve dynamic distribution of liquid oxygen according to the drilling depth, the flexible outer sleeve film is matched with the hole sealing filling body to form a pressure self-balancing structure, a wire network is excited in parallel to guarantee millisecond-level synchronous ignition of multiple pipes, and static electricity prevention and removal grounding guarantees construction safety.

The invention discloses a grounding resistance regular monitoring system and method, and belongs to the technical field of power equipment state monitoring. The system comprises a pulse generation module, a measurement module, a control module, a protection module and a communication module. The core lies in that a low-amplitude short-time-range direct-current pulse current is adopted to be injected into a grounding system, the pulse amplitude, width and frequency parameters are optimized to be always lower than the action threshold value of a relay protection device, and therefore accurate measurement is achieved on the premise that power is not cut off and misoperation is not caused. Meanwhile, historical data trend analysis and soil environment factors are fused, the deterioration trend of the grounding resistance is intelligently predicted, early warning is performed in advance, and a resistance reduction device can be linked for automatic adjustment. The method effectively solves the problems that a traditional measurement method needs power failure and is poor in interference resistance and an existing online monitoring technology is likely to trigger protection by mistake, and achieves safe, accurate, automatic and intelligent monitoring, operation and maintenance of the grounding resistance.

The invention provides a high-voltage cable sheath grounding fault diagnosis method and device and electronic equipment, and relates to the technical field of electrical fault diagnosis and detection. The method comprises the following steps: acquiring a multi-source state parameter, wherein the multi-source state parameter is used for representing a real-time operation state of a sheath grounding system corresponding to a high-voltage cable sheath; performing multi-source heterogeneous data processing on the multi-source state parameter to obtain a fundamental component and a harmonic component of the sheath current and a vibration energy value of the cable joint; determining a current fault type based on the multi-source state parameter, the fundamental component, the harmonic component and the vibration energy value; determining fault section position information based on the multi-source state parameters and the electric power topological graph of the high-voltage cable sheath; and determining a fault diagnosis result based on the current fault type and the fault section position information. The fault diagnosis method and device are used for improving the comprehensiveness and accuracy of fault diagnosis, reducing the possibility of misjudgment and missed judgment, and being convenient for maintenance personnel to quickly position and solve the fault problem so as to guarantee stable operation of a power system.

The invention provides an arc suppression coil grounding system zero-sequence overcurrent protection method based on zero-sequence voltage verification. The protection reliability is improved through multi-criterion fusion. The method specifically comprises the following steps: S1, arc suppression coil system fault starting criterion: monitoring a zero sequence voltage in real time, and triggering a protection algorithm when the amplitude of the zero sequence voltage exceeds a preset threshold value; s2, fault time calculation: calculating the duration time of a grounding fault based on the duration characteristic of the zero-sequence voltage; s3, fault position discrimination: in combination with the amplitude characteristics of the zero-sequence current, distinguishing an internal fault from an external fault; and S4, intelligent comprehensive decision making: fusing the transient and steady state characteristic quantities of the zero-sequence voltage and the zero-sequence current, and generating a protection action signal. According to the invention, by dynamically checking the correlation characteristics of the zero-sequence voltage and current, the problems of insufficient sensitivity and high maloperation rate of the traditional zero-sequence overcurrent protection in the arc suppression coil grounding system are effectively solved.

The invention relates to the field of grounding technology and electrical measurement, and discloses a grounding electrode current diffusion characteristic and environment correlation analysis method, which comprises the following steps: acquiring a ground electricity state vector representing soil electrochemical characteristics; constructing and calibrating a state phase space evolution model for describing time-space evolution of the vector; an adaptive dynamic analysis closed loop is executed, a state vector at the next moment and uncertainty are predicted through the model, an adaptive sensing protocol is generated based on the uncertainty to guide new data collection, a prediction result is corrected through new data, and a corrected state vector is obtained; and finally, based on the continuous corrected state vector, analyzing the causal association between the environment and the state, reconstructing three-dimensional complex conductivity distribution, and determining current diffusion characteristics such as grounding impedance through numerical calculation. According to the method, the limitation of static evaluation in the prior art is solved, and the dynamic prediction of the performance of the grounding system and the physical tracing of the abnormal cause are realized.

The embodiment of the invention provides a high-resistance grounding fault detection method and device, and the method comprises the steps: collecting the three-phase current of a preset monitoring point in real time, and enabling the preset monitoring point to be disposed at an incoming line of a multi-feeder line of a transformer substation; and according to the three-phase current and the three-phase current of the previous period, determining a three-phase current abrupt change composite quantity which represents the variable quantity of the unbalance degree of the three-phase current, and if the three-phase current abrupt change composite quantity is greater than a first preset threshold value, judging to start fault judgment. When fault judgment is started, whether a single-phase earth fault occurs in the multi-feeder line of the transformer substation or not is recognized according to the amplitude relation and / or the phase relation among the three-phase phase current break variables, and the three-phase phase current break variables represent the instantaneous variation of each phase current between adjacent periods. The method can effectively solve the problem that when the method is applied to a high-resistance grounding fault in a neutral point small-resistance grounding system, the detection precision is low due to the fact that the fault current is far lower than a conventional protection threshold value and other factors.

The invention discloses a neutral point ungrounded fault positioning device and method based on dynamic time window inversion, and belongs to the technical field of new energy power system fault detection. Aiming at the problems that most of the existing methods depend on single signal characteristics or fixed window length analysis and are difficult to adapt to time-varying characteristics and complexity of a fault transient process in a new energy current collection line, a sensor is used for sensing current generated between a transformer shell and a grounding point when a fault occurs, and dynamic time window selection and an integral inversion algorithm are combined, so that the time-varying characteristics of the fault transient process in the new energy current collection line are obtained. Processing and feature extraction are carried out on the voltage value, self-adaptive analysis of the fault transient waveform of the neutral ungrounded system is achieved, and fault features are accurately extracted. According to the method, the problems of fixed time window and insufficient feature extraction capability of a traditional method are solved, and the system fault positioning speed and precision are improved. In addition, the method can also realize real-time monitoring, fault positioning and data acquisition and storage of fault current, thereby improving the stability and operation and maintenance efficiency of the power system.

The invention provides a high-resistance grounding fault detection method, device and equipment and a storage medium, and the method comprises the steps: collecting a three-phase current and voltage signal of a small-resistance grounding system, and carrying out the processing of the three-phase current and voltage signal to obtain a zero-sequence current and a zero-sequence voltage; when the zero-sequence voltage energy characteristic meets a preset condition, calculating fault grounding resistance according to the zero-sequence current, the zero-sequence voltage and system electrical parameters; calculating a transient zero-sequence current characteristic value and a steady-state zero-sequence voltage characteristic value according to the fault grounding resistance, and comparing the characteristic values with a threshold value; and when the two characteristic values are both smaller than the corresponding threshold values, determining that the fault is a high-resistance grounding fault. According to the method, the fault grounding resistance is calculated, the transient state and steady state characteristic criteria are deduced based on the resistance, and the detection basis is converted from direct measurement of the fault current to analysis of the fault resistance characteristics, so that accurate identification of the low-current high-resistance grounding fault which is difficult to detect by a traditional method is realized.

The application discloses a method for simulating the parameters of a generator neutral point grounding system of an extended unit connection, which comprises an actual generator system and a simulated generator system in parallel operation, wherein the simulated generator system comprises a low zero sequence impedance transformer, a three-phase capacitor bank and a simulated generator neutral point grounding device; the parameter simulation test comprises the following steps: S1, relay protection configuration; S2, neutral point asymmetric voltage test of the generator neutral point grounding system of the extended unit connection; S3, neutral point displacement voltage test of the generator neutral point grounding system of the extended unit connection; S4, maximum capacitive current test of single-phase grounding of the generator neutral point grounding system of the extended unit connection; and S5, maximum fault current test of single-phase grounding of the generator neutral point grounding system of the extended unit connection. The application can effectively verify the grounding system performance of different grounding modes of the generator of the extended unit connection and determine whether the generator neutral point grounding mode meets the technical requirements.

A high-altitude double-grounding gas-filled cabinet gas tank structure comprises a gas tank formed by connecting a plurality of plates, the gas tank is filled with insulating gas, and the gas tank is divided into an upper gas tank, a middle gas tank and a lower gas tank along the height direction; the upper gas tank is internally provided with a first grounding system, the first grounding system is a two-station grounding switch and comprises a first guide sleeve and a first conducting rod, and one end of the first guide sleeve is provided with an insulation plugging structure, so that the first conducting rod can only move in a single direction; a second grounding system is arranged in the middle gas tank, the second grounding system is a three-station isolating switch, the three-station isolating switch comprises a second guide sleeve and a second conducting rod, and the two ends of the second guide sleeve are open, so that the second conducting rod can move in two opposite directions. Two sets of grounding systems are arranged, when one set of grounding system fails due to reasons, the other set of grounding system can still operate normally, and personal safety is guaranteed.

The application discloses a high-speed railway pantograph-catenary arc electromagnetic radiation interference modeling analysis method, constructs a pantograph-catenary arc-pantograph power supply system integrated model containing a traction substation model, a traction network model, a train traction transmission system model, a train-track return current grounding system model and a pantograph-catenary arc model; under a pantograph-off arc transient condition, arc current is obtained through simulation calculation; and based on the arc current, a relationship between arc radiation power and spatial equivalent electric field intensity is established to represent the influence of time-varying characteristics of traction network electrical parameters on pantograph-catenary arc electromagnetic radiation interference. Under the pantograph-off arc transient condition, the real-time changes of impedance and capacitive reactance parameters of the traction network are involved in the unified solution of arc current formation, radiation power evolution and spatial electric field intensity calculation, and meanwhile, key coupling factors of the train high-voltage system and the train-track grounding system are mainly considered, so that the accuracy and engineering applicability of pantograph-catenary arc electromagnetic radiation interference analysis are improved.

A fault detection system (800) for a medium voltage circuit comprises a power distribution cable (205), a first transformation center (210) comprising a first transformer and a first grounding conductor (603), a first grounding system comprising a first grounding resistor (RPAT1) connected to the first transformer via the first grounding conductor (603), the first transformation center (210) being connected to a first end of the cable (205), a second transformation center (220) comprising a second transformer and a second grounding conductor (603), a second grounding system comprising a second grounding resistor (RPAT2) connected to the second transformer via the second grounding conductor (603), the second transformation center (220) being connected to a second end of the cable (205).

A shaft grounding system for rotating electrical machinery includes a collar attachable to the shaft and presenting a circumferential contact surface of a first metal. A stator securable to the machine housing carries at least one resiliently biased contact element of a second metal that wipes against the contact surface to conduct unwanted charge from the shaft to ground. In preferred embodiments the metals are dissimilar and at least one is a noble metal. The system may incorporate multiple contact surfaces, modular contact elements and an on-board monitoring subsystem that provides local and remote diagnostics.

The utility model provides a GIS double grounding isolation knife switch, including base, mounting post, support device, support insulator, conductive system, grounding system, transmission system and operating mechanism, the base is equipped with the mounting post, the mounting post is equipped with the support device, the support device includes the support table and support rib plate, the support rib plate is equipped with the support insulator, the conductive system, the grounding system, the transmission system and the operating mechanism. The supporting rib plate is installed at the bottom of the supporting table, the supporting insulators are arranged on the two sides of the supporting table, the conductive system is located on the tops of the supporting insulators, and the conductive system is connected with the transmission system; the grounding system is mounted on the mounting column and is connected with the transmission system; the transmission system is located on the right side of the base, and the transmission system is connected with the operating mechanism; the operating mechanism comprises a hydraulic device and a control cabinet, the hydraulic device is arranged on the side face of the base, and the control cabinet is arranged in front of the base.