122 results about "Line resistance" patented technology

The invention discloses an electric energy quality loss test method, system and device and a medium. The method comprises the following steps: acquiring three-phase voltage data and three-phase current data; calculating the equivalent total loss power in the power distribution network line through the apparent power value, the voltage and the resistance based on the collected voltage and current data; and based on the equivalent total loss power, in combination with the power factors of different line losses, carrying out line loss subentry decoupling to obtain additional line losses caused by different electric energy quality problems. According to the invention, extra loss of the line caused by electric energy quality can be accurately measured, and line resistance does not need to be measured.

The invention relates to an electric drive system efficiency test compensation method, a storage medium and a program product, and relates to the technical field of new energy automobiles. The method is executed by a rack control system, and comprises the following steps: acquiring mechanical friction torque and friction mechanical power when a dynamometer idles; collecting the line resistance of a direct current bus between a power battery of the vehicle and a motor controller and the line resistance of a three-phase end line between a motor of the vehicle and the motor controller before the efficiency test; relevant parameters in the efficiency testing process are collected, wherein the relevant parameters comprise direct-current bus current, direct-current bus power, U-phase current, V-phase current, W-phase current, three-phase electric power, dynamometer rotating speed, dynamometer actual measurement torque and dynamometer mechanical power; according to the friction mechanical power, the line resistance of the direct current bus, the line resistance of the three-phase end line and related parameters, the efficiency compensation of the electric driving system is calculated, so that the accuracy of the efficiency test compensation calculation of the electric driving system is improved.

The invention provides a test structure and a test method thereof, which are applied to the technical field of semiconductors. In the invention, a first tested element and a second tested element are arranged in a mutually separated manner along a first direction, each pad group comprises a first sub-pad and a second sub-pad which are arranged in a mutually separated manner, electric connecting wires comprise a first electric connecting wire and a second electric connecting wire, and the sizes of the first sub-pad and the second sub-pad are set to be the same. The resistance values of the first electric connecting wire and the second electric connecting wire are the same, so that when the same probe is used for testing the first tested element and the second tested element, the contact resistances between the first sub-bonding pad and the second sub-bonding pad which are the same in size and the probe are the same; the resistance values of the first electric connecting line and the second electric connecting line with the same resistance value can be offset during difference operation, so that the influence of the contact resistance and the resistance of the electric connecting lines in the transistor element on the measurement accuracy of the on-resistance of the transistor element is avoided, namely, the purpose of reducing the measurement error is achieved.

The invention discloses a semiconductor structure, a manufacturing method thereof and electronic equipment. The semiconductor structure includes: an active pillar extending in a vertical direction; the word line extends along a first horizontal direction and is coupled with the active column to form a transistor; bit lines extending along a second horizontal direction and coupled to the active pillars, where the second horizontal direction intersects the first horizontal direction; wherein the word line comprises a first conductive pattern and a second conductive pattern, the first conductive pattern is provided with first openings and second openings, the first openings and the second openings are alternately arranged in the first horizontal direction, the active columns are located in the first openings, and the second conductive pattern is located in the second openings. The resistivity of the second conductive pattern is smaller than the resistivity of the first conductive pattern. The semiconductor structure is beneficial to reducing word line resistance and improving device performance.

The application provides an Ethernet-based linear series monitoring system and related equipment, the linear series monitoring system comprising a host device and a plurality of slave devices, a main power supply tap being led out from a secondary coil of each first coupling transformer, and an output end of a first power supply unit being connected with each main power supply tap; a primary tap being led out from a primary coil of each second coupling transformer, and a secondary tap being led out from a secondary coil of each third coupling transformer, a primary tap of an nth second coupling transformer in the same slave device being connected with a secondary tap of an nth third coupling transformer; and the primary taps of the N second coupling transformers in the same slave device all being connected with an input end of a rectifier unit. After the first power supply unit starts to supply power, parallel power supply is performed through 2N wires, so that the equivalent comprehensive line resistance is reduced, the voltage drop and loss are reduced, and the stability of line power supply is improved.

The utility model discloses a flexible circuit board of a battery module, and the flexible circuit board comprises a plugging terminal which is located at one end of the flexible circuit board in the length direction; the number of the nickel sheets is multiple, and the multiple nickel sheets are arranged at intervals in the length direction; the lead and the nickel sheet are respectively and independently connected with the plugging terminal through the lead; wherein the length of the wire and the width of the wire meet the following conditions: the length of the wire is less than or equal to 0.5 m, and the width of the wire is 0.444-0.500 mm; the length of the wire is greater than 0.5 m and less than or equal to 1m, and the width of the wire is 0.889-1.000 mm; the length of the wire is larger than 1m and smaller than or equal to 1.5 m, and the width of the wire is 1.333 mm to 1.500 mm. The utility model further discloses a battery pack. The flexible circuit board provided by the utility model effectively reduces the line resistance difference of the acquisition line of the whole battery module, thereby effectively reducing the voltage drop of the acquisition line and improving the acquisition accuracy.

The utility model relates to the technical field of electronic equipment, in particular to a camera module capable of preventing signal interference, which comprises a PCB (printed circuit board) and a fixed base, and is characterized in that the fixed base is positioned above the PCB and is fixedly connected with the PCB, a lens component is arranged on the fixed base, a sensing component is arranged on the surface of the PCB, and the lens component is positioned above the PCB. The lens assembly comprises a lens body, a wide angle and a protective cover, through cooperative use of the above structures, signal attenuation is reduced, a USB interface is close to the edge, connection with external equipment is facilitated, the integrity of USB signals is ensured through reasonable wiring layout, and for high-speed signals such as a camera image data transmission line, the data transmission efficiency is improved. A differential wiring mode is adopted, and the wiring length and spacing are strictly controlled so as to match impedance, reduce signal reflection, thicken power supply wiring, reduce line resistance, ensure the stability of power supply and reduce the power consumption of the camera.

An ammeter relates to the low-voltage electrical technology field. The invention provides an electric meter. The electric meter comprises a shell, a load switch and a wiring port, the load switch is arranged in the shell, the wiring port is arranged on one side of the shell, a magnetic system and a contact mechanism are arranged in the load switch, and the movement direction of a movable iron core of the magnetic system is perpendicular to the direction of the arrangement side of the wiring port on the shell; the contact mechanism is arranged between the magnetic system and the wiring port and is connected with the magnetic system and the wiring port. According to the ammeter obtained by the above design, the strong magnetic interference resistance of the load switch can be improved through the exquisite layout, the wiring of the load switch and the ammeter is simpler and more reasonable, the conductive loop is shorter, and the line resistance is reduced.

The invention discloses a maximum reactive voltage regulation method at the tail end of a rural power grid in an interference environment. According to the method, if it is monitored that the voltage of the load side of the tail end of the rural power grid is smaller than a first preset threshold value, reactive power increased according to a first preset rate is injected into the tail end of the rural power grid, and the ratio of line resistance to reactance of the rural power grid is larger than 1; in the process of injecting the reactive power to the tail end of the rural power grid, obtaining the voltage of the load side of the tail end of the rural power grid according to a preset time interval, and if the first difference value is smaller than a second preset threshold value and larger than a second difference value and the second difference value is larger than 0, controlling the magnitude of the injected reactive power to be unchanged, the first difference value is the difference value between the voltage obtained for the (i + 1) th time and the voltage obtained for the ith time, and the second difference value is the difference value between the voltage obtained for the (i + 2) th time and the voltage obtained for the (i + 1) th time, so that the voltage of the load side at the tail end of the rural power grid is always kept in a target state; and the dynamic balance between the power supply capability and the power demand is realized.

This disclosure provides a distributed control method and system for DC microgrids based on optimal power generation cost, relating to the field of distributed control technology for DC microgrids. Distributed control is achieved through controllers installed in each converter. Specifically, the method involves: acquiring operating data from adjacent converters to estimate global information of the DC microgrid; estimating the optimal current value based on the global information, and calculating the adaptive droop gain in real time using the optimal current value; compensating for voltage deviation based on the calculated adaptive droop gain and the line resistance of each converter to obtain the compensated bus voltage; and performing droop control and secondary voltage regulation control on the DC microgrid based on the adaptive droop gain and the compensated bus voltage to ensure that the output current of each converter tracks the optimal current value in real time, ensuring that the bus voltage remains stable at its rated value. Even under resistive load variations, this invention can still guarantee the optimal output current of each distributed converter, ensuring minimum power generation cost and achieving voltage stability.

The present application relates to the technical field of automatic guided vehicle power supply control and intelligent power distribution, and particularly relates to a mobile robot intelligent multi-channel controllable power distribution system and a short circuit protection method thereof, the system comprising: a sensing module, which collects environmental temperature and humidity, circuit board surface temperature, power supply channel input voltage and power supply channel output current, and receives target demand current to generate a set of operating parameters; a dew point calculation module, which calculates air dew point temperature based on the set of operating parameters. In the present application, by correlating multi-dimensional parameters such as environmental temperature and humidity, line resistance change, transient voltage drop and mechanical transmission resistance, the system can dynamically adjust the protection boundary by comprehensively considering the physical environment state and electrical operation data, reducing the difficulty in distinguishing between environmental interference and real electrical fault due to the use of fixed protection threshold, and improving the overall power supply stability of the automatic guided vehicle in complex scenarios such as temperature difference alternation and load mutation.

The utility model relates to the field of detection equipment, in particular to a detection device and current detection equipment. The detection device comprises a substrate, a sampling resistor and a plurality of reserved bonding pads. The plurality of reserved bonding pads are arranged on the substrate, the plurality of reserved bonding pads are connected in parallel, and at least one reserved bonding pad is welded with a sampling resistor; the reserved bonding pad comprises bonding pad assemblies which are oppositely arranged; the bonding pad assembly comprises a first bonding pad and a second bonding pad which are arranged at an interval; the first bonding pads of the bonding pad assemblies on the same side are connected with each other and are used for connecting a circuit to be detected; the second bonding pads of the bonding pad assemblies on the same side are connected with each other and used for being connected with a voltage detection line. One end of the sampling resistor is connected with the first bonding pad and the second bonding pad of the bonding pad assembly on one side of the reserved bonding pad, and the other end of the sampling resistor is connected with the first bonding pad and the second bonding pad of the bonding pad assembly on the other side of the reserved bonding pad. According to the detection device provided by the invention, the influence of the line resistance of the reserved bonding pad which is not welded with the sampling resistor on voltage detection can be avoided, so that the detection precision is improved.

The present invention discloses a sensor that integrates strain and temperature measurement. The sensor comprises a strain sensing unit, connecting leads, a flexible substrate, and a covering layer. The strain sensing unit and connecting leads are attached to the flexible substrate, and the covering layer seals the strain sensing unit and connecting leads. The connecting leads are connected to the strain sensing unit and include a first lead, a second lead, and a third lead. The second lead and the third lead are connected to the same output pin of the strain sensing unit. The sensor's first, second, and third leads form a three-wire measurement system, eliminating errors caused by line resistance and line strain due to excessively long leads. This allows for both temperature measurement and, using the measured temperature, compensation for temperature errors during strain measurement, further improving the sensor's measurement accuracy.

The utility model belongs to the technical field of low-voltage electric appliance detection, and particularly discloses a time constant suppression device of a direct-current short-circuit power supply, which comprises the direct-current short-circuit power supply, a compensation circuit and a test output circuit are electrically connected between the output end of the direct-current short-circuit power supply and a GND (ground), and the compensation circuit is connected with the test output circuit in parallel; the compensation circuit comprises a compensation circuit inductor, a compensation circuit resistor and a compensation capacitor which are connected in series; and the test output circuit comprises a line control switch and a test product access terminal which are connected in series. On the basis of the direct-current short-circuit power supply, the compensation circuit is connected in parallel, so that the time constant of the traditional direct-current short-circuit power supply can be suppressed, the inductance of the direct-current short-circuit power supply is equivalently reduced, the rise rate of the current in the initial stage is improved, and short-circuit current with smaller time constant is provided for the tested vehicle-mounted relay and fuse; and the short-circuit working condition test of the relay and the fuse for the electric vehicle is satisfied.

The invention provides a load balancing and voltage compensation method and device based on an electromagnetic element, and the method comprises the steps: controlling a zero-sequence current filter connected in parallel with a low-voltage power distribution network line, blocking the zero-sequence fundamental current and zero-sequence higher harmonic current of a load from flowing into a zero line, transferring the preset part of the maximum phase current in the three-phase load to the other two phases, reducing the maximum phase current and the line resistance voltage drop; controlling the three-phase multi-stage split-phase switched capacitor bank, compensating the reactive power of the line and reducing the negative sequence component of the current of the line, so that the current of the three-phase line reaches a preset balance degree value; reducing the overvoltage of the other two phases, increasing the voltage corresponding to the maximum phase current, and preventing the bidirectional out-of-limit of the voltage of the three-phase unbalanced load; and controlling a remote communication module to remotely monitor the running states of the zero-sequence current filter and the three-phase multi-stage split-phase switched capacitor bank. The stability and the electric energy quality of the power distribution network can be effectively improved.

The application belongs to the technical field of electric power, and provides a DC micro-grid system and a secondary control method of the DC micro-grid. The voltage compensation module, the droop control module, the steady-state current distribution compensation module, the dynamic current distribution compensation module and the voltage and current loop control module of the DC micro-grid system work cooperatively to ensure the accurate distribution of load current among different distributed power generation units, and improve the power quality and robustness of the DC micro-grid. The DC micro-grid system introduces compensation voltage to be used for bus voltage recovery and offsetting the influence of line resistance on the steady-state current distribution accuracy. The voltage and current loop control module adopts a cascaded voltage and current loop control mode to ensure that the output voltage of the distributed power generation unit converter closely tracks the reference output voltage, so as to realize the accurate distribution of load current among the distributed power generation units and improve the power quality of the DC micro-grid.

The invention discloses a low-voltage online resistance tester, which relates to the technical field of power equipment detection and comprises a high-precision sampling module, a power supply module, a temperature detection module, an LCD display module, a control and data processing module, a system clock module and a communication module. The low-voltage on-line resistance tester is a measuring instrument specially designed for electric power of a molded case circuit breaker, a relay, a contactor and the like, solves the problem that in the prior art, off-line measurement cannot meet the requirement for non-power-cut operation of a distribution network, and can perform high-precision wide-range resistance measurement between contacts when tested equipment is in an electrified state; therefore, the operation is convenient and fast.

The utility model provides a gun head line detection device, relates to the technical field of detection devices, and aims to solve the technical problem that a gun head line needs to be detected in the production process of a charging gun in the prior art. A gun head line detection device comprises a rack, a first connecting base, a micro-resistance tester, a safety tester and a control system, the first connecting base is connected to the rack and connected with at least two first sockets used for being connected with a gun head, the micro-resistance tester is connected to the rack, the safety tester is connected to the rack, and the control system is connected with the micro-resistance tester. The control system is electrically connected with all the first sockets, the micro-resistance tester and the safety tester; the control system selects the micro-resistance tester to carry out micro-resistance testing on each line, and if the resistance value of the line resistor is smaller than a set value, wiring is correct; and then the control system selects the safety tester to test the insulation resistance of each line, and if the insulation resistance is greater than a set value, the line is not damaged.

The invention discloses a line resistance compensation method for long-line transmission of a magnetic flux cable force sensor, and the method comprises the steps: installing the magnetic flux cable force sensor at a working measurement point for detection, adjusting a magnetic induction voltage signal outputted by the magnetic flux cable force sensor through a signal conditioner, and transmitting the magnetic induction voltage signal to a data processing system for processing through a high-speed analog-to-digital converter; the data processing system adopts a least square polynomial to fit the signal, and obtains a quantization integral value of a working measurement point; and taking the obtained quantized integral value of the working measurement point as an interpolation point, realizing optimization of the quantized integral of the working point by using a bilinear interpolation algorithm, and solving the relative permeability and the stress value of the working measurement point according to the optimized quantized integral value of the working point. According to the invention, the problem that the accuracy of cable stress measurement is influenced by factors such as sensor signal noise and cable impedance is solved, and the measurement precision of magnetoelastic effect stress detection of the magnetic flux cable force sensor is improved.

The invention relates to the technical field of electric signal processing, in particular to an impedance model construction method and system of a new energy flexible low-frequency sending-out system. The method comprises the following steps: recording real-time timing sequences of voltage and current of a converter bridge arm under different working conditions; extracting a time interval between the voltage peak value and the current peak value, a voltage waveform slope change rate and a current waveform oscillation period, and labeling corresponding working condition labels to form a bridge arm dynamic feature library; and identifying the voltage waveform and the current waveform of the converter bridge arm, and synchronously recording the line resistance and the line reactance between the converter stations. According to the invention, through integration of the bridge arm dynamic features, construction of the bridge arm dynamic feature library and high-frequency correction cooperation, adaptive optimization of bridge arm parameters and construction of the impedance model of high and low frequency bands are realized, so that the matching efficiency of the impedance model is improved.

A semiconductor structure includes a plurality of vertical transport field effect transistors, and an interconnect structure connected to one of respective source / drain regions of at least two vertical transport field effect transistors of the plurality of vertical transport field effect transistors and respective gate regions of the at least two vertical transport field effect transistors. The interconnect structure comprises a damascene portion, and a subtractive portion disposed on the damascene portion.

The application belongs to the field of inverter network type control, and discloses a schedulable virtual oscillator control method based on a consistent algorithm adaptive virtual resistance. a 、 β Two-phase output voltage, coordinate transformation is carried out on the output voltage to obtain u d3 、 q3 ; reactive power Q1 on the inverter side and reactive power Q2 on the load side are input into reactive power distribution control to obtain distribution error uQ1, and then virtual impedance correction term deltaQ1 is obtained, deltaQ1 is input into adaptive virtual impedance to obtain dynamic impedance L V1 and R V1 , i d , i q are multiplied by L V1 and R V1 to obtain virtual voltage u d2 and u q2 ; u d2 is subtracted from u d3 to obtain u d4 , u q2 is subtracted from u q3 to obtain u q4 , u d4 and u q4 are input into voltage and current double closed loop to obtain a pwm signal. The application can solve the problem that the dynamic stability of the existing virtual oscillator is strictly required for line parameter ratio, can guarantee power quality when the line resistance and inductance ratio changes, reduces the design difficulty, and increases the dynamic stability of the system.

The air conditioner comprises the steps that the environment temperature of an electric heating device is detected, and the resistance R1 of the electric heating device is obtained through calculation; the first switch is controlled to be switched on, the electric heating device works, the voltage detection circuit collects power grid voltage data, and the collected voltage data is processed in a first processing mode to obtain first power grid voltage V1; the first switch is controlled to be switched off, the electric heating device stops working, the voltage detection circuit collects power grid voltage data, and the collected voltage data is processed in a first processing mode to obtain second power grid voltage V2; the second power grid voltage V2, the first power grid voltage V1 and the electric heating device resistor R1 are subjected to first logical operation to obtain a power grid line resistor R2; when the power grid line resistance R2 is larger than the resistance threshold RY, power grid line fault early warning is triggered; whether the power grid where the air conditioner is located has abnormal conditions such as poor wiring or line aging loss increase can be judged through the power grid line resistance, and fault early warning is achieved.

The present invention belongs to the technical field of line resistance network analysis, and discloses a fast line resistance network analysis method for a non-volatile memory array, comprising: establishing KCL equations for electrodes in all rows and columns of the line resistance network of the non-volatile memory array; transforming and decomposing the voltage lines and coefficient matrices in the KCL equations, introducing a fixed-point iteration algorithm, and iteratively calculating the voltage distribution of the top and bottom nodes of the array. The originally complex large-scale linear equations problem is converted into two smaller-scale sub-problems. The two sub-problems are solved by mutual iteration, thereby reducing the computational complexity and computational memory. The method of the present invention can predict and evaluate the impact of IR-drop on the acceleration of neural network calculations during the design phase. Advantages include: high accuracy, capable of simulating the impact of IR-drop with an accuracy of more than 95%; low computational complexity, reducing the computational complexity from O((2mn) 2 ) is reduced to O(mn); the memory load is small, minimizing memory usage while maintaining high accuracy.

The application relates to the field of new energy grid connection technology, and discloses a parameter identification method, device and equipment based on a park energy system and a medium, the method comprising: acquiring a plurality of to-be-identified parameters of the park energy system, the plurality of to-be-identified parameters comprising line resistance, line inductance, line capacitance, capacity of a wind power converter, capacity of a photovoltaic inverter, transformer short-circuit impedance, proportional gain coefficient of the photovoltaic inverter, integral gain coefficient of the photovoltaic inverter, control parameter of the wind power converter and harmonic attenuation coefficient; generating a comprehensive deviation corresponding to each parameter combination according to a comprehensive deviation function, selecting a parameter combination with the minimum comprehensive deviation as a target parameter combination of the park energy system, and completing grid connection of the park energy system and a public power grid according to the target parameter combination. The application can improve the identification efficiency of the target parameter combination of the park energy system, and the target parameter combination can provide strong guarantee for safe grid connection of the park energy system.

The invention provides a novel single-stage current source type direct current power flow controller, and aims to solve the problem of power flow regulation and control between distributed renewable energy sources and a direct current power grid. The controller reduces the loss of the transformer through a partial power flow mode, has the ZCS soft switching capability, and reduces the power conversion loss. The topological structure is composed of a transformer primary side half-bridge, a transformer and a secondary side half-bridge, and power flow regulation and control are achieved by adjusting output voltage. The controller can effectively work during bidirectional tidal current flow, and is suitable for occasions with large line resistance change. Simulation verification shows that the controller has excellent adjusting capability and efficiency in a Plecs environment, and powerful support is provided for flexible control of a direct current power grid.

The invention belongs to the technical field of power electronic equipment, and particularly provides an active damping constant-power control method for a common-high-frequency-link direct-current transformer and a medium, and the method comprises the steps: firstly obtaining a port direct-current side current i2 at a constant-power operation mode port of the common-high-frequency-link direct-current transformer; in the active damping constant-power controller, port direct-current side current i2 at a constant-power operation mode port is used as input, and an output value yc is obtained after the port direct-current side current i2 passes through an active damping unit; after the port current error ei2 passes through a PI regulator, an output value yc of the active damping unit is superposed to obtain an intermediate quantity yd; and finally, amplifying the intermediate quantity yd through a gain amplification unit to generate a phase shift ratio d2 of the constant-power operation mode port, and outputting the phase shift ratio d2 to the constant-power operation mode port to control the constant-power operation mode port to operate. According to the scheme, on the premise that the actual line resistance is not additionally changed and the loss is not increased, the operation stability of the common-high-frequency-link direct-current transformer can be effectively improved, and low-frequency oscillation is restrained.

The utility model relates to the technical field, and discloses a virtual battery voltage and current calibration device, which comprises a PC end, a main control board, a channel switching board, a 485 expansion board, a 6019 reference source and a virtual battery cell PACK board, the main control board, the 485 expansion board and the 6019 reference source are all connected to the output end of the PC end, the output end of the 485 expansion board is connected to the input end of the virtual battery cell PACK board, and the output end of the channel switching board is connected to the input end of the virtual battery cell PACK board. The virtual cells can be calibrated at the same time at a time through a PC, real-time calibration in a working environment can be achieved by starting the calibration device when the whole BMS test system runs, compared with traditional single-board calibration, precision errors caused by contact resistance and line resistance generated when a single board is connected into the system are reduced, and the accuracy of the whole BMS test system is improved. The difficulty that the test system needs to be disassembled for secondary calibration when the precision of the single board is abnormal is avoided, the time cost and the labor cost are reduced through one-key calibration, and high-precision calibration and disassembly-free calibration are realized through calibration in the system.

The utility model provides an on-line resistance detection device, which is used for detecting the resistance of a sample to be detected and comprises a support table body, conductive wheels arranged on the support table body at intervals, two conductive shafts electrically connected with the conductive wheels respectively, and a resistance tester arranged on the support table body, the resistance tester is electrically connected with the two conductive shafts, and the conductive wheel is used for being electrically connected with the sample to be tested. According to the on-line resistance detection device, the conductive wheel is electrically connected with the sample to be detected, so that on-line resistance detection of the sample to be detected can be realized without stopping production, the sample to be detected does not need to be damaged, the production does not need to be stopped, waste is greatly reduced, production cost is reduced, and production efficiency is improved. The time is fully utilized, and whether the production process needs to be adjusted or not is fed back to production in real time.

The invention discloses a multi-loop current balancing method, and belongs to the technical field of current control. According to the method, a line resistance calculation model is established based on the number of lap joint bolts, cable length, cable sectional area, cable resistivity, copper bar length, copper bar sectional area, copper bar resistivity and lap joint bolt contact resistance; establishing a target function based on the cable material cost and the copper bar lap joint cost by taking the lowest reference cost as a target; based on the objective function and the line resistance calculation model, adjusting the cable length and the number of lap joint bolts of each loop until the current deviation rate of each loop is less than 5%, and obtaining the optimal cable length and the optimal number of lap joint bolts of each loop; and S3, calculating the actual current deviation ratio of each loop based on the actual current of each loop under the condition, and if the actual current deviation ratio is not less than 5%, returning to execute the step S3 until the actual current deviation ratio is less than 5%. According to the invention, the realization cost can be greatly reduced while multi-loop current equalization is realized.