49 results about "Ground impedance" patented technology

A power transmission tower grounding resistance non-contact measurement method based on the electromagnetic coupling principle comprises the following steps that transmitting and receiving electromagnetic coupling coils are arranged around an iron tower grounding body, and geometric calibration and spatial positioning of a measurement area are completed by combining grounding grid structure parameters and soil conduction characteristics; injecting a high-frequency alternating-current excitation signal into the transmitting coil, and synchronously acquiring the amplitude and phase response of the induced voltage at a receiving coil end; carrying out filtering processing on the induction signal by adopting a time-frequency analysis and phase decoupling algorithm, and solving a function relationship between electromagnetic response and grounding impedance by combining a coupling equivalent model; based on experimental calibration data and scene parameters, a nonlinear mapping model of induction response and grounding resistance is constructed, and real-time inversion calculation is carried out by combining a solving result obtained in the third step. According to the invention, the real-time accurate measurement of the grounding resistance under the conditions of no power failure and no wire breakage is realized, and the safety, the operation convenience and the anti-interference capability in a complex environment in the measurement process are obviously improved.

The invention belongs to the technical field of electromagnetic detection, and relates to an electromagnetic detection multi-level current emission system for a plateau environment and a control method. The control method comprises the steps of calculating load model impedance; analyzing an MFPWM control process, and determining an optimal control parameter by using an optimization target of transmitting spectrum intensity maximization; and MFPWM optimization control: realizing directional power distribution and independent regulation and control of each frequency component by adjusting the frequency and amplitude of each modulation signal component. A multi-level topological structure is adopted, high output voltage is achieved while switching voltage stress is reduced, and the problems that cost rises and system complexity is too high due to the fact that a traditional H-bridge inverter depends on high power supply voltage are solved; by matching with multi-frequency pulse width modulation optimization control, spectrum energy can be flexibly configured, high-frequency components of transmitted signals are enhanced, and the spectrum energy utilization rate and the signal-to-noise ratio are improved; grounding impedance changes in a high dynamic range can be accurately tracked, and the requirements of deep geological electromagnetic detection in an extreme environment are met.

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 invention discloses a transformer substation electromagnetic interference source modeling and positioning method based on multi-physics field coupling, relates to the technical field of interference positioning, is used for solving the problem of insufficient positioning precision of an electromagnetic interference source, and aims at solving the problem of low positioning precision of the electromagnetic interference source by collecting grounding potential data of a grounding grid monitoring node, calculating a potential deviation index and judging whether discharge abnormality exists or not. And when an abnormality occurs, accessing a historical database to call grounding impedance data of the marked grounding electrode, analyzing an impedance fluctuation trend, detecting a discharge current amount in each discharge direction, marking the grounding electrode by combining a discharge imbalance characteristic, dividing and screening an abnormal corrosion area, and obtaining surface magnetic field data and surface temperature data of each divided area. A discharge concentration coefficient is calculated through magnetic field distribution characteristics and a surface temperature coefficient, a positioning index is generated in combination with discharge path data, a discharge positioning area is screened, and the corrosion positioning precision and maintenance effectiveness of the grounding grid are improved.

This invention discloses a method and system for assessing the grounding resistance status of transmission towers, relating to the field of grounding measurement technology for transmission towers. The method includes: acquiring a grounding impedance characteristic sequence and a three-dimensional environmental characteristic sequence; calculating the comprehensive environmental influence intensity index for each cycle; calculating the response lag coefficient for the current cycle; calculating the dominant weight index of environmental effects for the current cycle; constructing and training two types of hidden Markov models, independent and joint, to obtain the independent observation probability and joint observation probability of each hidden state in the current cycle; based on the independent and joint observation probabilities, obtaining the corrected observation probability of each hidden state in the current cycle; based on the corrected observation probabilities, calculating the confidence level of each hidden state in the current cycle, and determining the grounding resistance status for the current cycle. This invention can dynamically distinguish between normal current dissipation capacity fluctuations caused by the environment and real anomalies caused by equipment degradation, improving the accuracy of grounding status assessment.

The application provides a parallel cavity shared radio frequency power supply system and a radio frequency adjusting method for a plasma process, which comprises the following steps: collecting the ground potential of the cavity wall of each parallel process cavity in real time through a detection and adjusting module, dynamically adjusting the ground impedance of each radio frequency coil, and balancing the total ground impedance of each branch; then, completing independent dynamic impedance matching of each branch by a matching module, eliminating the power distribution imbalance problem caused by the inconsistent impedance of each radio frequency coil, keeping the plasma discharge state of the multiple cavities consistent, improving the process uniformity of each cavity, and greatly reducing the equipment cost by using only one radio frequency power supply.

The invention relates to an alternating current ice melting reactive compensation control method considering ground wire impedance change, which belongs to the technical field of alternating current ice melting, and comprises the following steps: S1, connecting a reactive compensation device into an ice melting loop, and injecting ice melting current into an overhead ground wire through an alternating current power supply; s2, measuring the length and the temperature of the ground wire in the ice melting process through a sag and temperature sensing and monitoring assembly; s3, on the basis of the ground wire impedance change model in the ice melting process, ground wire impedance change is calculated according to the ground wire length and the ground wire temperature; s4, substituting the ground wire impedance value into the heat effect theoretical model, and calculating the required reactive compensation capacity in combination with the temperature rise and the current effective value; and S5, based on the optimal array algorithm, controlling the reactive power compensation device to switch the switching capacitor bank array combination of the corresponding reactive power compensation capacity.

The utility model provides a kind of ground impedance detection device based on harmonic analysis, belong to ground impedance detection technical field, including main frame assembly, the inner wall of main frame assembly is connected with ground impedance detector, the outer wall of main frame assembly is fixedly connected with limiting component, the outer wall of main frame assembly is provided with honing component, the outer wall of main frame assembly is provided with side support component, the outer wall of main frame assembly is provided with take-up assembly;The utility model is provided with take-up assembly, in use, by take-up motor driving take-up rod rotation, and then realize the orderly winding of the wire connected with probe or ground electrode test point, avoid multiple wires between each other cross each other, improve the accurate detection of ground impedance detector in field use;By the setting of limiting component, in use, start and control rotary motor use, drive press plate rotation, so that multiple spring barrels are above ground impedance detector.

The invention relates to the technical field of lightning protection grounding lightning rods, and discloses a centering type lightning protection grounding lightning rod for a base station, which is suitable for lightning protection of GNSS base stations and similar communication base stations, and comprises a vertical rod, a lightning rod, an equipotential connecting plate, a GNSS base station, a control box, a vertical grounding body, a lower lead, a bottom lead and a multi-stage supporting, fixing and pressure injection structure, the lightning rod realizes joint equipotential grounding with the base station and the plurality of vertical grounding bodies through the equipotential connecting plate, the coaxial centering layout is adopted, the grounding impedance is effectively reduced, the rapid reinforcement and stabilization of the vertical grounding bodies are realized and the pull-out resistance of the grounding bodies is improved through the supporting and fixing part and drilling and fixing part structures, and the device also integrates the function of pressure injection of a resistance reducing agent, so that the device is convenient to use. The ground effect is further optimized, the aviation obstruction beacon and the solar power supply panel are integrally designed, the visibility of equipment is improved, the ground performance is excellent, the lightning protection safety of the base station can be remarkably improved, and the ground lightning protection device is suitable for the lightning protection ground requirement of a field GNSS (Global Navigation Satellite System) base station.

A ground monitoring device connectable to the electrical system of an RV, boat or other vehicle or to a remote or shore AC power supply, is configured to monitor the ground impedance by a direct connection to the AC power supply. In one feature, the ground monitoring device can include the capability to disconnect the electrical system of the vehicle from the AC power supply if the impedance exceeds a predetermined threshold.

The invention discloses an underground comprehensive pipe gallery grounding system model and a grounding system analysis method, when the underground comprehensive pipe gallery grounding system model is laid, cable arrangement is incorporated, the influence of a cable structure on grounding impedance is considered, and the shunting condition of current on the cable in practice is also considered, so that the grounding system model is more accurate and reliable. And the accuracy of grounding impedance calculation is further improved. The excitation current is hit on the cable to simulate that the fault current is firstly transmitted through a cable shielding layer when the cable has a fault and then flows to a grounding grid at each grounding point position, so that the working conditions of different fault grounding points are simulated, and the change characteristics of the grounding impedance when the fault occurs at each position are analyzed and compared; and determining the stability of the system.

A dynamic evaluation method for grounding resistance of a power transmission tower comprises the following steps: designing a frequency-adjustable variable-frequency excitation signal source, and providing a stable alternating current signal to support excitation of different frequencies to a grounding system of the power transmission tower and provide a signal basis for subsequent impedance measurement; a high-precision voltage and current sensor module is built and connected with a frequency conversion signal source, impedance data under different frequencies are collected by measuring voltage and current response of a grounding system in real time, and original data are provided for model building; establishing a frequency response model of the grounding resistance, determining the relationship between the grounding impedance and the excitation frequency through data fitting, and providing a mathematical basis for dynamic evaluation; a dynamic evaluation algorithm is designed, and in combination with a real-time monitoring system, ground resistance change is evaluated in real time, abnormity is detected, early warning is triggered, and stable operation of the system is ensured. According to the invention, high-precision dynamic measurement and real-time evaluation of the grounding resistance are realized, and the stability and reliability of the grounding system under different working conditions are also significantly improved.

The invention discloses a grounding device conduction state degradation trend early warning method and system. The method comprises the following steps: measuring conduction impedance between every two of a plurality of grounding down lead measuring points in a grounding grid according to a preset test path; calculating a grounding impedance value of each grounding down lead measuring point based on the plurality of conduction impedance measured values obtained through measurement; extracting a grounding impedance value of each grounding downlead measuring point according to a time sequence to form a grounding impedance historical data sequence of each measuring point, fitting the sequence to establish a degradation trend model of the grounding impedance along with time, and predicting according to the degradation trend model to obtain a resistance prediction value of each grounding downlead measuring point in future time; and constructing a comprehensive evaluation model based on the resistance predicted value, and outputting a corresponding risk level prompt according to a range in which an evaluation result of the comprehensive evaluation model is located. According to the invention, early and advanced early warning of the latent fault of the grounding device can be realized, and the active safety and economy of power grid operation are improved.

The present application belongs to the technical field of electromagnetic detection, and relates to an electromagnetic detection multi-level current emission system and control method for highland environment. The control method comprises calculating a load model impedance; analyzing an MFPWM control process to determine optimal control parameters for an emission spectrum intensity maximization optimization target; and MFPWM optimization control: by adjusting the frequency and amplitude of each modulation signal component, directional power distribution, independent regulation and control of each frequency component are realized. The present application adopts a multi-level topology structure, which realizes high output voltage while reducing switching voltage stress, avoids the cost increase and high system complexity caused by the dependence of traditional H-bridge inverters on high power supply voltage; in combination with multi-frequency pulse width modulation optimization control, the spectrum energy can be flexibly configured, the high-frequency component of the emission signal is enhanced, and the spectrum energy utilization rate and signal-to-noise ratio are improved; the high dynamic range ground impedance changes can be accurately tracked, and the needs of deep geological electromagnetic detection in extreme environments are met.

The invention provides an electromagnetic interference suppression method in the electrifying process of an electric connector. Comprising the following steps: starting a multi-parameter monitoring module to collect grounding impedance, temperature variation, working frequency and a multi-core crosstalk coupling coefficient when the electric connector works; quantifying the total interference voltage of the electric connector through an interference coupling calculation module based on the acquired grounding impedance, temperature variation, working frequency and multi-core crosstalk coupling coefficient; a self-adaptive offset phase is calculated through a self-adaptive phase offset circuit according to the quantized total interference voltage, and an adjustable inductor is adjusted to realize phase offset of interference; the shielding effectiveness is corrected through the grounding-phase correction shielding layer according to the calculated self-adaptive offset phase and the collected grounding impedance, and the interference suppression stability can be ensured in a high-frequency scene.

The application belongs to the technical field of power grid power supply, and particularly relates to a measurement method and system for tower grounding resistance, which comprises the following steps: constructing a chain linear network model, setting an engineering typical value of the grounding impedance of each tower, constructing a prior admittance matrix, inverting the prior admittance matrix to obtain a prior impedance matrix, injecting a mixed excitation current signal with multiple different frequencies into the grounding lead of the measured tower, synchronously collecting the measured voltage of all nodes, separating the measured voltage under each frequency, calculating an admittance deviation matrix and an impedance deviation matrix, establishing an approximate linear relationship between the impedance deviation matrix and the admittance deviation matrix and a voltage difference vector, solving the approximate linear relationship, obtaining the impedance deviation of the grounding impedance under each frequency relative to the engineering typical value of the grounding impedance, calculating the actual grounding impedance, and separating the actual grounding impedance to obtain the grounding resistance. The application realizes the inversion of the grounding resistance from the external port measurement value without disassembling any grounding lead.

Disclosed are an insulation impedance detection circuit (10), a control method and control apparatus therefor, and a photovoltaic device. The insulation impedance detection circuit (10) is used for detecting a ground impedance of a direct-current bus; the direct-current bus comprises a positive electrode bus (PV+) and negative electrode buses (PV-); the insulation impedance detection circuit (10) comprises sub-detection circuits; the sub-detection circuits each comprise a positive electrode detection resistor (R1) and a negative electrode detection resistor (R2), and are used for detecting bus voltages between the positive electrode bus (PV+) and the negative electrode buses (PV-) by means of the positive electrode detection resistors (R1), and detecting negative ground voltages of the negative electrode buses (PV-) by means of the negative electrode detection resistors (R2); the sub-detection circuits comprise a first sub-detection circuit (102) and a second sub-detection circuit (104); resistance values of the positive electrode detection resistor (R1) and the negative electrode detection resistor (R2) in the first sub-detection circuit (102) are not equal; and resistance values of the positive electrode detection resistor (R1) and the negative electrode detection resistor (R2) in the second sub-detection circuit (104) are equal.

The application provides a heavy haul railway rail potential and traction return current determination method, device and equipment, the method comprises the following steps: obtaining the basic parameters of the target heavy haul railway traction power supply system, the per-meter grounding impedance of the bridge and the per-meter grounding impedance of the tunnel; dividing the target heavy haul railway into a roadbed section, a bridge section and a tunnel section; determining the roadbed section impedance matrix, the bridge section impedance matrix and the tunnel section impedance matrix respectively; constructing the voltage equation and the current equation corresponding to the roadbed section, the bridge section and the tunnel section respectively, and determining the rail potential and the traction return current of the target heavy haul railway in combination with the equivalent model of the traction power supply system transformer. Different voltage equations and current equations are constructed for the roadbed section, the bridge section and the tunnel section to determine the rail potential and the traction return current, the topographic information along the heavy haul railway is fully considered, the accuracy and the calculation efficiency of the rail potential and the traction return current can be improved, and the universality is high.

The invention discloses a biological electric shock simulation experiment platform, system and device and a medium, and belongs to the technical field of power system safety and fault simulation. Calculating a difference value between each half wave and the first half wave; setting an electric shock threshold value and an inter-class variance maximum value; judging an electric shock threshold value; and performing secondary judgment according to the result of judging the electric shock threshold. The biological electric shock experimental platform has the beneficial effects that the operating environment of a power distribution network is truly simulated through the three-phase power supply, the voltage regulator and the RC ground impedance module, and an electric shock loop is constructed by adopting an animal experiment body, so that the defect that the traditional VR / AR training lacks real electrical characteristic feedback is overcome; and electric shock fault features can be accurately captured and identified by cooperating with a fault recorder to monitor electrical parameter changes in real time and an intelligent identification method based on a half-wave difference value and an inter-class variance algorithm.

The invention provides an evaluation and analysis method and system for the corrosion state of a grounding system, and belongs to the technical field of evaluation and analysis, and the method specifically comprises the steps: carrying out the evaluation and analysis of the corrosion state of an impedance deviation tower according to a preset method, and carrying out the evaluation and analysis of the corrosion state of an impedance deviation tower based on the impedance deviation tower data not in a grounding impedance interval; determining an updated identification scheme of the evaluation and analysis method for the corrosion state of the transmission line tower in each grounding impedance interval, and utilizing the updated identification scheme of the evaluation and analysis method for the transmission line tower in each grounding impedance interval to identify the corrosion state of the transmission line tower. And whether the transmission line tower needing grounding system processing exists in the grounding impedance interval of the target is determined, so that the accuracy of evaluation, analysis and processing of the corrosion state is improved.

The invention provides a monitoring optimization setting method and system for a grounding device of a power transmission tower, and belongs to the technical field of energy storage power stations, and the method specifically comprises the steps: determining the change condition of the soil humidity of the power transmission tower based on the detection data of a soil humidity detection device, and when the change condition does not meet the requirement, determining the grounding device of the power transmission tower; according to the change data of the soil humidity of different power transmission line towers and the setting data of the soil humidity detection devices of the adjacent power transmission line towers, the monitoring target of the grounding impedance is determined, and the reliability of monitoring processing of the grounding impedance in the region where the soil humidity changes severely is improved.

The invention discloses an inverter system and a night insulation resistance detection method thereof. The method comprises the following steps: calculating a ground insulation resistance value of a negative electrode of a first equivalent bus by using an insulation resistance detection circuit in a detection unit; a switching tube in the DC / DC unit is driven to be switched on, so that the photovoltaic array input end positive electrode ground impedance and the photovoltaic array input end negative electrode ground impedance in the photovoltaic array unit are equivalently connected in parallel; an insulation resistance detection circuit is used to calculate a ground insulation resistance value of the negative electrode of the second equivalent bus; according to the first equivalent bus negative electrode ground insulation resistance value and the second equivalent bus negative electrode ground insulation resistance value, the photovoltaic array input end positive electrode ground insulation resistance in the photovoltaic array unit is calculated, and therefore the problem that the photovoltaic array input end positive electrode ground insulation resistance cannot be detected at night is solved. And the safety of the inverter system during operation at night is further improved.

A grounding impedance measurement apparatus and method, and an inverter are provided. The measurement apparatus includes a signal source, a coupling impedance network, a voltage division network, a sampling module, and a controller, the coupling impedance network is connected to the signal source, and couples an excitation signal between a direct-current input terminal and an alternating-current output terminal of an inverter; the voltage division network performs voltage division on the voltage between the direct-current input terminal and the alternating-current output terminal to provide a divided voltage; the sampling module is connected to the voltage division network, samples the divided voltage, and acquires a sampled voltage; and the controller is connected to the signal source and the sampling module, respectively, and acquires a grounding impedance of the direct-current input terminal of the inverter.

The application discloses a self-adaptive intelligent transformer grounding device for uneven ground, which comprises a connecting column, an insulating sleeve, a liquid storage pipe, a plurality of rotating frames, a torsional spring, a limiting frame, a plugging assembly and a stabilizing assembly. The outer periphery of the liquid storage pipe is compounded with a shear thickening fluid bag body layer, and the inside is filled with an electric field responsive electrorheological fluid; the plugging assembly comprises a guide column and a first spring, a direct current electric field can be applied between the guide column and the connecting column to make the electrorheological fluid change from a liquid phase to a solid phase; the rotating frames are circumferentially distributed, are not connected with each other and have independent rotating axes, and the limiting frame is removed to make each rotating frame independently expand and adhere to the hole wall under the driving of the torsional spring. Through the triple synergistic mechanism of shear thickening impact hardening, electric field regulation of electrorheological fluid and mechanical structure multi-point decoupling, dynamic reversible adjustment of grounding impedance and full-scale hole wall self-adaptive adhesion are realized.

Ground impedance may have adverse effects on the performance of RF circuits that employ shunt switches. The disclosed methods and devices address this issue. The methods and devices involve the use of resonance-canceling inductors to counteract the capacitive reactance caused by parasitic capacitances and / or decoupling capacitors utilized in such systems. Solutions that incorporate series resistors to distribute the resonance across the frequency band of operation are also described. Additionally, devices that employ digitally tuned capacitors to shift the resonance frequency outside the operational band are presented.

The present application relates to lightning protection grounding lightning rod technical field, disclose a kind of centering lightning protection grounding lightning rod for base station, it is applicable to the lightning protection of GNSS base station and similar communication base station, the device includes vertical pole, lightning rod, equipotential bonding plate, GNSS base station, control box, vertical grounding body, lower lead, bottom lead and multistage bracing and pressure injection structure, lightning rod is connected with base station and multiple vertical grounding body by equipotential bonding plate and realizes joint equipotential grounding, adopt coaxial centering layout, effectively reduce grounding impedance, through bracing and drill fastening structure, realize the quick reinforcement and stabilization of vertical grounding body, improve the pullout resistance of grounding body, the device is also integrated with the function of pressure injection resistance reducing agent, further optimize grounding effect, aviation obstruction light and solar power supply panel integrated design, improve the visibility of equipment, the grounding performance of the present application is excellent, can significantly improve the lightning protection safety of base station, it is applicable to the lightning protection grounding demand of field GNSS base station.

The invention provides a process grounding system ground loop grounding impedance test system and method, and the system comprises an impedance analyzer which is used for providing an excitation signal with a specified frequency required by a test, measuring voltage and current between a first grounding grid leading-out point and a second grounding grid leading-out point set on a process grounding grid of the particle accelerator grounding system; the test clamp is connected with the impedance analyzer through a connecting line, is used for connecting the first grounding grid leading-out point and the second grounding grid leading-out point to the impedance analyzer through a test line and an auxiliary test line respectively, and is used for the impedance analyzer to inject an excitation signal and measure the excitation signal; and the impedance analyzer control module is connected with the impedance analyzer and is used for controlling test parameters and flow of the impedance analyzer, reading measurement data of the impedance analyzer, processing the measurement data, acquiring grounding impedance between the first grounding grid leading-out point and the second grounding grid leading-out point at a specified frequency and generating a resistance-frequency curve.

This application belongs to the field of power grid supply technology, specifically a method and system for measuring the grounding resistance of power poles. The method includes constructing a chain-like linear network model, setting typical engineering values ​​for the grounding impedance of each power pole, constructing a priori admittance matrices, inverting the priori admittance matrix to obtain a priori impedance matrix, injecting multiple mixed excitation current signals of different frequencies into the grounding leads of the power pole under test, simultaneously acquiring the measured voltages of all nodes, separating the measured voltages at each frequency, calculating the admittance deviation matrix and impedance deviation matrix, establishing an approximate linear relationship between the impedance deviation matrix, admittance deviation matrix, and voltage difference vector, solving the approximate linear relationship to obtain the impedance deviation of the grounding impedance relative to the typical engineering value of the grounding impedance at each frequency, calculating the actual grounding impedance, and separating the actual grounding impedance to obtain the grounding resistance. This application enables the direct inversion of grounding resistance from external port measurements without disassembling any grounding leads.

The utility model discloses an integrated EMC (Electro Magnetic Compatibility) suppression structure for a power supply module. The integrated EMC suppression structure comprises a composite shielding layer, a multi-stage filtering assembly and a low-impedance grounding structure, a metal shielding cover in the composite shielding layer is matched with a ferrite wave-absorbing layer, so that interference of different frequencies can be inhibited; the multi-stage filtering assembly is provided with different filtering circuits at the input end, the power device pin and the output end respectively, and broadband conducted interference suppression is achieved. The low-impedance grounding structure utilizes four layers of PCBs and conductive silica gel, reduces grounding impedance and gives consideration to heat dissipation, and through collaborative design of the composite shielding layer, the multi-stage filtering assembly and the low-impedance grounding structure, conduction and radiation interference are reduced, and meanwhile, the heat dissipation performance is taken into consideration.