578 results about "Current electric" patented technology

The invention discloses an accurate zero crossing point control method for a built-in relay of a large-current electric energy meter, which relates to the technical field of power electronics and intelligent metering and comprises the following steps of: receiving a power grid voltage digital signal, determining a voltage zero crossing point by comparing symbol changes of adjacent sampling values, establishing a phase corresponding relation between voltage and current, and calculating a current phase corresponding relation; generating current zero crossing point prediction data; when a relay switching instruction is received, the specific moment of the next current zero crossing point is calculated, and the control signal sending moment is determined; a relay driving control signal is sent, the actual action completion moment of the relay is collected, the deviation from the expected zero crossing moment is calculated, and the mechanical action delay time parameter of the relay is corrected. By predicting the current zero-crossing time and considering the mechanical action delay characteristic of the relay, accurate switching of the built-in relay at the actual current zero-crossing point is achieved, meanwhile, the self-adaptive adjusting capacity is achieved, the arc energy during large-current switching is reduced, the service life of the relay is prolonged, and the reliability of the electric energy meter is improved.

The invention discloses a high-precision charging pile direct-current electric energy metering method based on ripple compensation, and relates to the technical field of charging pile control. Dual-path signal acquisition and processing are executed to obtain a direct-current component metering result and ripple characteristic parameters; averaging the sampling points to obtain a high-frequency direct current component; subtracting the high-frequency direct-current component from the original sampling signal to obtain a pure ripple signal, performing FFT conversion and time domain analysis on the pure ripple signal, and extracting ripple characteristic parameters; according to the charging pile direct-current electric energy high-precision metering method based on ripple compensation, a main metering path and ripple analysis path dual-path architecture is adopted, the main path guarantees the direct-current component metering precision through a low-sampling-rate and high-precision ADC, the ripple path only extracts features rather than reconstructs waveforms, high hardware cost is not needed, and the charging pile direct-current electric energy metering precision is improved. Metering errors caused by ripples can be reduced to meet and be superior to national standard requirements. The transient scene is defined through the ripple mutation coefficient Ktrans and the ripple decay time tau, and the problem that the transient precision of a traditional method is out of control is solved.

The invention provides an air-ground integrated reconfigurable intelligent surface energy transmission system, and belongs to the technical field of wireless power supply systems, and the system comprises a visual perception module which is used for obtaining image information of a monitoring area, carrying out the recognition and positioning of an energy receiving target based on the image information, and outputting a target coordinate; the control calculation module calculates phase regulation and control parameter coordinates required for driving the reconfigurable intelligent surface based on the received target; the energy transmission module dynamically adjusts the wavefront phase of the electromagnetic wave based on the phase regulation and control parameter coordinates to form an energy focus point at the position of the energy receiving target; the energy receiving module is arranged on an energy receiving target and used for receiving the electromagnetic energy at the energy focus point and converting the electromagnetic energy into direct-current electric energy. According to the invention, the three technical fields of high-precision real-time sensing, intelligent signal processing and advanced electromagnetic beam control are deeply integrated, and remote, high-efficiency and automatic charging for a plurality of freely moving devices is realized.

The invention relates to the technical field of electrical parameter measurement, in particular to an SOC prediction method and system applied to a lithium battery. The method comprises the following steps: collecting an electrical variable parameter set of the lithium battery in a current operation period, and determining an electric quantity change value and a change trend of terminal voltage; dividing a voltage response state of the lithium battery in each operation stage to determine an operation state mapping relation; predicting the state of charge of the lithium battery in the current operation period by using the operation state mapping relation; in response to the first change of the operation condition of the lithium battery, collecting a current electrical variable parameter set of the lithium battery to correct the operation state mapping relation; and predicting the state of charge of the lithium battery after the first change of the operation condition according to the corrected operation state mapping relation. The method is beneficial for dynamically adapting to unsteady state behaviors of the lithium battery in different working states, SOC prediction lag and fluctuation caused by working condition changes are effectively reduced, and the dynamic response capability and reliability of prediction are improved.

The invention provides a bus voltage adjusting method of a compressor, the compressor and electronic equipment. The bus voltage adjusting method of the compressor comprises the steps that the current current of the quadrature axis of a motor corresponding to the compressor and the current rotating speed corresponding to the compressor are collected; determining whether the current meets a first preset condition or not, and determining whether the current rotating speed meets a second preset condition or not; and when one of the first preset condition and the second preset condition is met, increasing the bus voltage of the compressor. According to the bus voltage adjusting method of the compressor, one of the current current of the quadrature axis of the electrode corresponding to the compressor and the current rotating speed of the compressor serves as a reference, so that the bus voltage is increased, the rotating speed of the compressor can be guaranteed, and the overall efficiency and performance are improved.

The invention discloses a dynamic electromagnetic shielding method for a complex electromagnetic environment and a shielding device thereof, and the method comprises the steps: obtaining real-time voltage data in the complex electromagnetic environment, carrying out the voltage feature analysis, outputting a feature vector of a real-time voltage signal, and analyzing the type of an interference source of a current electric field according to the feature vector, performing interference trend time sequence prediction processing on the feature vector through a pre-trained LSTM model according to the interference source type to obtain a time domain voltage value and a phase deviation value, and performing composite loss coefficient calculation on the time domain voltage value and the phase deviation value to obtain a composite loss coefficient; and performing reverse offset signal synthesis processing on the voltage interference signal according to the calculated composite loss coefficient, performing coil dynamic activation processing on a preset multi-coil array according to the synthesized reverse offset signal, generating a directional offset magnetic field corresponding to the real-time electromagnetic interference, and performing electromagnetic offset shielding on the current electromagnetic interference. According to the invention, transient interference can be responded in time, and the electromagnetic shielding effectiveness can be improved.

The invention discloses a low-voltage distribution box temperature rise abnormity identification method based on an improved fuzzy clustering algorithm. The method comprises the following steps: S1, generating a temperature-current synchronous acquisition data set according to a time sequence; s2, constructing a load-temperature difference weight matrix in combination with the current current amplitude; s3, obtaining a current membership matrix and a cluster center set; s4, calculating the membership slip amount of each measuring point according to the current membership matrix and the membership matrix at the previous moment, and generating a temperature rise trend state sequence; s5, judging whether the temperature rise trend state sequence has a measuring point which continuously slides from the normal cluster to the risk cluster or not; if yes, corresponding cluster centers in the corresponding cluster center sets are extracted and mapped to the physical coordinates according to the measuring point index table, and positioning information containing the measuring point numbers, the types of the electrical parts and the risk levels is generated. According to the invention, the fault positioning accuracy and the operation and maintenance efficiency are greatly improved.

The invention discloses an electric spark nondestructive testing evaluation method for the integrity of a waterproof layer of a cable trench, and belongs to the technical field of nondestructive testing, and the method comprises the following steps: applying a multi-frequency electric signal through a preset moving electrode; the initial contact pressure of the moving electrode and the surface of the waterproof layer is obtained in real time, the pressure of the contact position of the moving electrode is adjusted, an electric spark signal generated at the defect position of the cable trench waterproof layer by a multi-frequency electric signal applied by the moving electrode is captured, and characteristic parameters of the electric spark signal are extracted to generate current electric spark characteristic data; utilizing the current electric spark characteristic data to distinguish defect types so as to generate a defect evaluation result; and outputting defect distribution information and triggering an acousto-optic alarm according to a defect evaluation result. According to the method, a detection mode of combining multi-frequency electric signal excitation and electric spark signal feature extraction and analysis is adopted, waterproof layer defect types can be distinguished, the severity of the waterproof layer defects can be evaluated, and the detection accuracy is improved.

The invention discloses an NFC trigger control method integrating wireless charging and automatic data backup, and relates to the field of data backup. The method comprises the following steps: realizing equipment identity authentication and electric quantity information acquisition through an NFC trigger mechanism, dynamically calculating target charging power based on the current electric quantity, and monitoring the equipment temperature in real time in a wireless charging process. By calculating the difference value between the working upper limit temperature and the real-time temperature of the storage chip, a pre-trained reading frequency determiner is used for intelligently generating a real-time reading frequency parameter, and the working state of the storage chip in the data backup process is dynamically regulated and controlled. A cloud collaborative optimization mechanism is further introduced, the confidence coefficient weight of each determination unit is dynamically adjusted according to historical accuracy data, and self-adaptive optimization of the reading frequency determiner is achieved. According to the method and the device, the problem of equipment overheating during concurrent execution of wireless charging and data backup is effectively solved, the balance of charging efficiency, backup safety and equipment thermal management is realized, and the user experience is remarkably improved.

The invention discloses a heavy-load freight direct-current electric locomotive on-board platform and a train operation curve calculation method. Step-by-step iterative optimization is carried out through a dynamic programming algorithm. Presetting operation steps and step lengths, and defining a selectable action set in each step length; and with the current state of the train as a starting point, evaluating each action in the action set in each iteration step, and calculating the next train state which may be transferred to. And evaluating all possible train state changes by adopting a target cost function, sorting according to the cost values from small to large, and preferentially selecting the action with the minimum cost value for subsequent calculation. And if all the action cost values of the current step exceed the limit, backtracking to the previous iteration step for reselection. And after iteration to the maximum step number, storing all train state changes, and finally obtaining an optimal train operation curve under the constraint of the target function. The method optimizes a control strategy through a dynamic programming algorithm, improves prediction precision, optimizes action selection, accelerates convergence, reduces redundancy, and improves operation stability, safety and algorithm efficiency.

The invention relates to the technical field of energy storage assemblies, in particular to an energy storage converter and an energy storage system. The energy storage converter comprises a first shell, and the first shell is provided with an accommodating cavity; the energy storage converter further comprises a high-voltage box which is accommodated in the accommodating cavity. Wherein the high-voltage box is provided with a bearing assembly, and the bearing assembly is used for bearing electric devices in the high-voltage box, so that the electric devices in the high-voltage box are separated from other electric devices in the energy storage converter. Through the design mode, electric parts in the high-voltage box can be accommodated in the bearing assembly, direct-current electric parts in the high-voltage box and alternating-current electric parts in the energy storage converter are prevented from interfering with each other in the use process, and normal use of the energy storage converter and the high-voltage box is guaranteed. Through the arrangement of the bearing assembly, the integrated design of the high-voltage box and the energy storage converter is achieved, meanwhile, direct-current electric devices in the high-voltage box can be separated from alternating-current electric devices in the energy storage converter, and normal use of the energy storage converter and the high-voltage box is guaranteed.

The invention discloses a wireless low-power-consumption meter reading method and system for an electric energy meter, and relates to the technical field of intelligent management, the basic standby energy consumption of the electric energy meter in a standby state is analyzed, the standby power of the electric energy meter is determined, a standard handshake request packet is continuously sent according to a set initial wake-up period, and in combination with the intensity level of a successful feedback signal, the standby power of the electric energy meter is determined. Analyzing the communication reliability level of the area where the current electric energy meter is located, and determining a communication reliability coefficient; analyzing the power consumption condition of the electric energy meter in the initialization stage, obtaining a total power consumption value, and determining the residual operation cycle duration by combining the residual operation cycle condition of a battery in the electric energy meter; analyzing the sustainable operation level of the electric energy meter in the remaining operation cycle, and determining a sustainable operation index; and judging whether the electric energy meter is in a low-power-consumption sustainable operation state or not in the remaining operation cycle, outputting a wake-up control instruction of a corresponding level, and executing a wireless low-power meter reading task according to a corresponding wake-up cycle.

The invention discloses a self-adaptive suspension type outer wall cleaning unmanned aerial vehicle system and method based on constant tension control, and relates to the technical field of outer wall cleaning unmanned aerial vehicles. The system comprises a cleaning unmanned aerial vehicle subsystem, a water and electricity supply guarantee subsystem and an intelligent suspension retraction subsystem which are connected through a photoelectric liquid composite mooring rope; the intelligent suspension take-up and pay-off subsystem comprises a constant-tension take-up and pay-off device which monitors and adjusts the tension of a mooring rope in real time so as to maintain a constant micro-tension state, and it is ensured that the unmanned aerial vehicle flies stably. The water and electricity supply guarantee subsystem provides high-voltage direct-current electric energy and high-voltage fluid; the cleaning unmanned aerial vehicle subsystem comprises a self-adaptive telescopic spraying rod, and the position of a nozzle is dynamically adjusted according to the building facade structure so as to execute cleaning operation. By integrating constant tension control, high-voltage power supply and a self-adaptive cleaning mechanism, high efficiency, flight stability and operation safety of outer wall cleaning operation are achieved.

The invention relates to the technical field of electric pole burial depth measurement, in particular to an electric pole burial depth nondestructive measurement method, system, equipment and medium, and the method comprises the steps: coaxially installing a first sensor and a second sensor on the side wall of an electric pole at a preset interval along the axial direction of the electric pole; impact excitation is applied to the side wall of the electric pole, vibration signals of the first sensor and the second sensor are synchronously collected, and a dual-channel time domain signal is obtained; calculating the wave velocity of the elastic wave in the current electric pole according to the arrival time difference of the head wave in the dual-channel time domain signal and a preset interval; based on the calculated wave velocity and the dual-channel time domain signal, performing signal processing and statistical analysis on a plurality of samples obtained by multiple times of measurement so as to identify the arrival time difference corresponding to the stable uplink reflected wave; and calculating the burial depth of the electric pole according to the identified arrival time difference and wave velocity of the uplink reflected wave. The method has the beneficial effects that the risk of high-altitude operation is thoroughly avoided through double-sensor side wall installation and intelligent algorithm decoupling.

The invention relates to the technical field of barium chloride production and preparation, in particular to a purification method of electronic-grade barium chloride, which comprises the following steps: S1, washing witherite tailing barium slag with hydrochloric acid to obtain barium-containing filter residue; s2, mixing the barium-containing filter residues with hydrochloric acid, and performing leaching treatment to obtain a crude barium chloride product; s3, dispersing the barium chloride crude product in water, adjusting the pH value of the solution, adding an impurity removal agent, carrying out ultrasonic-assisted segmented temperature control treatment, and filtering to obtain a barium chloride solution; and S4, adding a crystal form control agent into the barium chloride solution, and performing programmed cooling crystallization under the action of a low-intensity direct-current electric field to obtain the electronic-grade barium chloride. According to the technical scheme, efficient conversion and precise impurity separation of the barium slag difficult to treat are achieved, the technical problems that in a traditional method, the barium recovery rate is low, impurity removal is difficult, and the product purity is unstable are solved, and the resource utilization rate of barium is remarkably increased.

The invention discloses a lubricating oil system of an aviation turboprop engine. The lubricating oil system comprises a lubricating oil supercharging device, an oil-gas separation device, a lubricating oil return device, a lubricating oil filtering device, a lubricating oil monitoring device and a connecting guide pipe communicating all the devices. The lubricating oil supercharging device comprises a main lubricating oil pump, an auxiliary lubricating oil pump and a torque measuring pump; the oil-gas separation device comprises a ventilation oil tank, an air separator and an oil mist separator; the lubricating oil return device comprises a lubricating oil tank, a lubricating oil radiator, a middle and rear bearing oil well pump, a transmission box oil well pump and a direct-current electric lubricating oil pump; the lubricating oil filtering device comprises a lubricating oil filter and a middle-rear bearing oil return filter; the lubricating oil monitoring device comprises a temperature metal chip annunciator and a magnetic chip detection annunciator. Appropriate lubricating oil pressure and oil quantity are provided, lubrication and heat dissipation of friction surfaces of parts in an engine are improved, and the use reliability of the engine is improved.

The invention discloses an electric power construction behavior safety detection method and system, and relates to electric power safety. The method comprises the following steps: collecting historical electric power work ticket data, and constructing a work ticket risk feature library; according to the work ticket risk feature library, training a risk identification model based on multi-task learning; collecting text data of the current electric power work ticket, extracting work content and security measure fields, and generating a text feature vector; searching optimal parameter configuration in a parameter space of the risk identification model by using a discretization doliolaria optimization algorithm; the method comprises the following steps: collecting real-time image data of a working site, carrying out target detection and feature extraction on the image data, identifying position coordinates of working personnel and types and wearing state marks of safety protection appliances, encoding a detection result into structured data, and generating an image feature vector; aiming at the lack of a dynamic association verification mechanism between an electric power work ticket text specification and an actual behavior of a work site in the prior art, the static requirement of a work ticket is converted into a dynamic behavior supervision standard.

The invention provides a photovoltaic direct-current micro-grid lighting system in a tunnel scene, and the system comprises a photovoltaic power generation unit which comprises a distributed photovoltaic module and is used for converting light energy into direct-current electric energy; the direct-current micro-grid unit comprises a direct-current bus, an energy storage device and a micro-grid control cabinet, and efficient and direct utilization of clean energy is achieved by constructing a photovoltaic direct-current micro-grid; through intelligent sensing and linkage control of traffic flow and ambient light, the lamp can move along with the vehicle and illuminate according to needs, and energy is remarkably saved; the direct-current illumination three-level protection unit comprises a data protection unit, a direct-current measurement and control module and a lamp cap protection chip, and the data protection unit learns line characteristics on line and dynamically compensates voltage drop; the three are integrated to effectively solve the problem of voltage stabilization of the distributed direct current lighting system, the reliability and lighting quality of the system are improved, and an efficient, stable and intelligent tunnel green lighting solution is formed.

The invention discloses an intelligent operation and maintenance method and system for a battery replacement cabinet, relates to the field of intelligent battery replacement, and solves the technical problems that adaptive matching of an electric vehicle and a battery is difficult to perform according to characteristics of an electric vehicle user, and dynamic demand setting of data of the battery replacement cabinet is neglected. According to the invention, the data is acquired based on the dynamic acquisition frequency by acquiring the dynamic acquisition frequency of the acquired data of each power conversion cabinet; based on the residual electric quantity of the external battery, recommending a target battery replacement cabinet for the current electric vehicle to perform battery replacement and a corresponding priority factor; determining a to-be-fetched factor of each storage battery based on the priority factor and the residual electric quantity and the battery charging frequency of each storage battery in the target battery replacement cabinet; determining an available factor of the current electric vehicle based on the number of illegal battery replacement times, and matching the to-be-fetched factor with the available factor to determine a battery replacement battery; reminding and guiding the electric vehicle to perform battery replacement based on the battery replacement battery; according to the invention, the matching degree of the battery replacement battery and the electric vehicle can be improved, and the service life of the new battery is prolonged.

The invention belongs to the technical field of resource recycling of waste photovoltaic panels, and discloses a green metallurgical method for recycling high-purity silicon, silver and copper from waste photovoltaic panels, which comprises the following steps: (1) disassembling the photovoltaic panels to obtain laminated components, and crushing and screening to obtain light silicon powder and metal-enriched fine powder; (2) leaching the metal-enriched fine powder by using a citric acid-hydrogen peroxide mixed solution; (3) silver ingots are recycled through precipitation and electrolysis; (4) electrolyzing to obtain electrolytic copper; and (5) performing magnetic separation, alkali washing, acid washing, spark plasma sintering and direct-current electric field solidification purification on the silicon powder to obtain the high-purity silicon ingot. A leaching system composed of citric acid and hydrogen peroxide is adopted, so that the method has the advantages of no toxic gas emission, easiness in waste liquid treatment and low cost, and unification of efficient resource recovery and environmental protection is realized.

The application relates to the technical field of lightning protection equipment manufacturing, and discloses a composition for preparing a high-stability direct-current resistance sheet, the high-stability direct-current resistance sheet, a preparation method and application thereof. The composition contains the following components: ZnO, Bi2O3, Sb2O3, Co2O3, MnO2, Cr2O3, SiO2, NiO, SnO2, BN, Al(NO3)3.H2O and silver glass powder. The resistance sheet prepared by using the composition has high stability. In addition, the method can avoid resistance sheet grain coarsening, increase the non-uniformity of the internal microstructure and increase the number of pores; the excellent basic electrical performance of the direct-current resistance sheet can be ensured. Meanwhile, the method can make the electrical performance change of the resistance sheet under current impact and the continuous direct-current electric field smaller, and the performance is more stable.

At present, in the prior art, a mechanical type cannot accurately control temperature, but a semiconductor type needs to dissipate heat, the service life of a semiconductor power tube is influenced by long-time overheating, and a temperature adjusting mode of an existing electric food warmer is fixed increment and decrement each time, so that contradiction is generated between rapid adjustment and accurate adjustment. According to the electric food warmer, the temperature controller in a mechanical mode and the thermal power execution device are connected in series to play a role in double-insurance overheating protection, meanwhile, semiconductor and relay dual-mode control is added, the maximum current with the maximum power is distributed to the relay, the power burden of a semiconductor power tube is reduced, and the service life of the electric food warmer is prolonged. And the multi-level automatic increment change of the knob and the temperature increase and decrease amount switching of the knob are realized.

The present application provides a liquid ejecting apparatus capable of improving safety against abnormality. An alternating-current electric field generating section has a first electrode and a second electrode which are arranged adjacent to each other, a high-frequency voltage generating section which generates a high-frequency voltage to the first electrode and the second electrode, and a conductor which electrically connects the first electrode and the second electrode to the high-frequency voltage generating section. A control section stops generation of the high-frequency voltage from the high-frequency voltage generating section to the first electrode and the second electrode based on a result detected by a detection section which detects a change in the alternating-current electric field generated from the alternating-current electric field generating section.

The application discloses a vehicle control method and device. The method comprises the following steps: determining a speed interval in which an actual speed of a motor is located according to a current gear of a vehicle; determining a current electric torque of the motor according to an electric torque boundary value and a speed boundary value corresponding to the speed interval in which the actual speed is located, and determining a current braking torque of the motor according to a braking torque boundary value and a speed boundary value corresponding to the speed interval in which the actual speed is located; when a brake pedal of the vehicle is released, determining a current acceleration of the motor according to an acceleration boundary value and a speed boundary value corresponding to the speed interval in which the actual speed is located, and determining a current deceleration of the motor according to a deceleration boundary value and a speed boundary value corresponding to the speed interval in which the actual speed is located; and controlling the motor to operate according to the current electric torque and the current acceleration or according to the current braking torque and the current deceleration, so as to control the vehicle to operate. The technical scheme of the application improves the accuracy of vehicle control.

The embodiment of the invention provides a power equipment health monitoring method and system fusing spatial-temporal characteristics and semantic information, and belongs to the technical field of power equipment health monitoring. The power equipment health monitoring method comprises the steps that historical multi-source data of power equipment are acquired, the historical multi-source data are preprocessed, and the historical multi-source data comprise time sequence data, spatial data and semantic data; extracting time sequence features, spatial features and semantic features of the preprocessed historical multi-source data; carrying out feature fusion on the time sequence features, the spatial features and the semantic features; constructing and training a health state evaluation model according to the fusion features; therefore, the health state of the current power equipment can be rapidly and accurately evaluated based on the real-time data of the current power equipment, and the reliability and safety of the operation of the power equipment are effectively improved.

The utility model provides a kind of medical head lamp control system, belong to medical head lamp technical field, involve control box, remote controller and LED load component.Control box contains time length calculation module, encoder module, displacement module, limit module and in-position detection module.Time length calculation module can monitor the power condition of system in real time, and according to current LED current gear, calculate the remaining available time of system;Displacement module is used to drive encoder module to move up and down, and limit module is designed to limit its position, so that users can operate the keys and knobs of encoder module, realize the switch control and dimming control of system;Special LED power plug is used, combined with in-position detection module inside control box, the connection condition of load light source can be detected in real time, the system saves power and gives an alarm when abnormally connected, and load LED can be protected to avoid damage.The scheme can improve the operation convenience and safety of head lamp system.

Current surge is managed by estimating the current demand based on the actual instructions being executed and then adjusting the clock for the static schedule. For statically scheduled instructions, the compute elements synchronously execute the instructions according to the static schedule. The synchronization is provided by a common clock that is used to clock the instruction execution by the compute elements. As instructions are being executed, their current consumption may be estimated based on the type of instruction. The current consumptions for the instructions executed by the compute elements may be aggregated, providing an estimate of the aggregate current demand. This can then be used to adjust the clock accordingly.

[Problem] To provide a charge control system for efficiently charging each of a plurality of electric vehicles while minimizing surplus power of usable electric power and without exceeding an upper limit value of a set current when the plurality of electric vehicles are charged. [Solution] When periodic connection is received from individual chargers 200, a charge control device 300 compares the value of already used current with an upper limit value indicated by set current information to identify the remaining power value of usable current. The charge control device 300 increases the value of the charging current of the chargers 200 in cases where the identified remaining power value is equal to or greater than a prescribed threshold value, and determines the value of the charging current of the chargers 200 so as to reduce the value of the charging current of the chargers 200 in cases where the remaining power value is less than the threshold value. The charge control device 300 transmits the determined value of the charging current to the chargers 200, and controls charging of electric vehicles by the chargers 200.

The present application relates to a kind of offshore wind power dc collection system single-end protection method based on transient current rate of change, the transient fault current of each collection line of dc collection system is calculated, the transient fault current is the difference between current value and steady-state current value before fault;The transient current rate of change of each line positive and negative is calculated;If the inter-pole unbalance voltage is greater than the first voltage threshold, then start monopolar ground fault protection process, according to the polarity and amplitude relationship of the transient current rate of change of each line positive and negative, determine fault line and fault pole;If the inter-pole measurement voltage is less than the second voltage threshold, then start bipolar short-circuit fault protection process, according to the polarity and amplitude relationship of the transient current rate of change of each line positive and negative, determine fault line and fault pole.Compared with prior art, the present application has the advantages of high accuracy, high adaptability and strong reliability.

This application relates to a control method, system, and related equipment for compressor demagnetization current protection. The method includes: acquiring the current value of the compressor during operation; converting the current value to obtain the stator resistance value of the compressor; acquiring the compressor temperature corresponding to the stator resistance value; determining the demagnetization current value corresponding to the temperature range where the compressor temperature is located as the demagnetization current protection setpoint according to a pre-established correspondence between demagnetization current values ​​and temperature ranges; and performing protection control on the compressor based on the demagnetization current protection setpoint. This application solves the technical problems in the prior art where compressor demagnetization current protection uses a fixed current protection value and an adjustment method based on ambient temperature, resulting in inaccurate protection and untimely response. It achieves more accurate and timely protection, while optimizing the compressor's performance at different temperatures, improving safety and the range of motor applications.