170 results about "Current transformer" patented technology

The invention discloses a direct-current transformer control method, which relates to the technical field of power electronic control and comprises the following steps of: acquiring operating parameters of a direct-current transformer in real time; the operation parameters at least comprise input side voltage, output side voltage and load current; inputting the operation parameters into a model prediction controller; in the model prediction controller, on the basis of the operation parameters and a preset system model, calculating to obtain a switching device control signal which enables a control target in a future preset time domain to be optimal; a switching device control signal is applied to a switching device of the DC transformer to regulate its output voltage or power. The method has the advantages that the dynamic response speed is increased, the system robustness is enhanced, and multi-target optimization control is realized.

The utility model relates to the technical field of equipment disassembly, and discloses a disassembly tool which comprises a fixed seat, a mounting structure is arranged on the fixed seat, and the mounting structure is suitable for clamping at least part of the fixed seat to the top of an integrated cabinet; a sliding assembly; the hoisting assembly comprises a pulley assembly and a traction piece. According to the disassembling tool, in the field environment, even if a foundation is a stone muddy road surface and the carrying space is limited, transportation and stable installation can be guaranteed, the position of the hoisting assembly can be flexibly adjusted, a converter can be conveniently hoisted at different positions, and the disassembling tool is suitable for various complex field layouts; according to the utility model, the traction piece can be operated manually, so that the problem that an electric tool cannot be used due to inconvenience in on-site electricity taking is avoided, the cost of the tool is greatly reduced, and the tool is convenient to carry and operate.

The invention relates to a transformer area group optimization method and device, computer equipment and a readable storage medium. The method comprises the following steps: obtaining voltage, current and frequency of each edge node in a to-be-optimized transformer area group, photovoltaic output data of the transformer area group, energy storage charge and discharge state data and electric vehicle charging power data, and presetting various operation constraints set for the transformer area group; and inputting the voltage, the current, the frequency, the photovoltaic output data, the energy storage charge and discharge state data, the electric vehicle charging power data and the various operation constraints into a pre-constructed multi-target optimization model, obtaining optimization strategies meeting the various operation constraints, and performing optimization guidance on the operation of the transformer area group according to the optimization strategies. The transformer area group level multi-objective optimization task is calculated through the cloud high-performance computing cluster, so that an optimization strategy which is more adaptive to the current transformer area group is obtained, edge setting is controlled according to the optimization strategy to execute optimization output, and the load balance and operation robustness of the transformer area group are ensured.

The invention discloses an overvoltage suppression method of a resonant direct-current transformer and the resonant direct-current transformer, and relates to the technical field of power electronics. The overvoltage suppression method of the resonant direct-current transformer comprises the following steps: detecting a direct-current output voltage provided by a direct-current output port, and comparing the direct-current output voltage with an output voltage target value of the resonant direct-current transformer; and under the condition that the direct current output voltage is greater than the output voltage target value, dynamically adjusting the internal phase shift delay between the control signals of the first half bridge and the second half bridge so as to adjust the direct current output voltage to be less than or equal to the output voltage target value. According to the embodiment of the invention, the suppression cost of the light-load overvoltage of the resonant direct-current transformer can be reduced, and the reliability of the resonant direct-current transformer is improved.

This invention discloses a winding device for transformer production with tension adjustment function, relating to the field of transformer production technology. The winding device includes a wire feeding frame, a positioning seat, and a power seat. The wire feeding frame is equipped with several fixed shafts. Compared with current transformer production winding devices, this invention achieves dynamic adjustment of wire tension, significantly improving winding accuracy. Through the cooperation of the brake disc and brake at the end of the fixed shaft on the wire feeding frame, the friction force can be adjusted in real time according to the wire feeding speed, ensuring stable wire tension during winding and effectively avoiding problems such as loose coils, excessive tightness, or coil stacking. This invention also includes a positioning mechanism with an eccentricity correction function. During the winding process, if the transformer skeleton axis deviates, the correction component can apply a fine-tuning force to the end of the transformer skeleton to automatically compensate for the eccentricity, making the transformer skeleton axis coincide with the top rod axis again.

A modular multi-level direct-current transformer topology applicable to a multi-voltage-class direct-current power grid, and a control method therefor. The topology comprises a bridge arm inductor, an upper bridge arm, a lower bridge arm and a filter inductor, wherein one end of the bridge arm inductor is connected to a positive electrode of a high-voltage side, and the other end thereof is connected to one end of the upper bridge arm; the other end of the upper bridge arm is connected to one end of the lower bridge arm and one end of the filter inductor; the other end of the lower bridge arm is separately connected to a negative electrode of the high-voltage side and a negative electrode of a low-voltage side; the other end of the filter inductor is connected to a positive electrode of the low-voltage side; and the upper bridge arm and the lower bridge arm each comprise a sub-module string, the sub-module string comprising several sub-modules, which are sequentially connected in series, and the upper bridge arm and the lower bridge arm regulate respective bridge arm voltages by means of controlling the number of inserted sub-modules, so as to realize direct-current voltage conversion between different voltage classes. In the present application, the use of upper and lower sets of chained sub-modules reduces the use of complex assemblies, thereby reducing the cost and the control difficulty, and also improving the safety, reliability and efficiency of a system.

The invention discloses a high-voltage high-power cascade converter which comprises rectifier diodes, a direct-current input bar, an IGBT device, a low-inductance busbar, a cascade output bar, a radiator, a cover plate, a shell assembly and a control assembly. The fuse and the supporting capacitor are detachably connected with the converter through the low-inductance busbar. The radiator is located at the bottom of the shell assembly, a cooling medium connector is arranged on the side portion of the radiator, and the cover plate is used for sealing the top of the shell assembly. The plurality of rectifier diodes and the plurality of IGBT devices are installed on the radiator, and the low-inductance busbar is used for connecting terminals of corresponding polarities of the rectifier diodes and the IGBT devices; the direct current input bar and the cascade output bar are both located above the IGBT device and are arranged in a staggered manner; the DC input bar is connected with the support capacitor through the low-inductance busbar. The cascade output bar adopts a copper bar mode; the control assembly is located above the cascade output row. The invention has the advantages of compact structure, convenience in maintenance, high power and the like.

The invention discloses an alternating-current dynamic power source, which belongs to the field of power sources, and comprises the following steps: a main controller controls a JAWS quantum voltage generator unit to emit a first alternating-current voltage and a second alternating-current voltage according to an output parameter and a time-frequency reference source; the voltage adjusting device carries out voltage conversion processing on the first AC voltage to obtain a first test AC voltage; the current converter performs current conversion processing on the second AC voltage to obtain a second test AC voltage; the voltage acquisition unit calculates a first differential voltage value according to the first AC voltage and the first test AC voltage, and calculates a second differential voltage value according to the second AC voltage and the second test AC voltage; and the main controller calculates the compensation active electric energy according to the first differential voltage value and the second differential voltage value, and compensates the theoretical active electric energy according to the compensation active electric energy to obtain the actual active electric energy. Therefore, by implementing the method, the problem that the electric energy traceability requirement of any wave dynamic load cannot be met in the prior art can be solved.

The invention relates to a power transformer on-line monitoring method, system and device and a medium. An existing power transformer on-line monitoring method cannot carry out self-adaptive adjustment on an operation environment. The method comprises the following steps: acquiring operation data and environment data of a transformer in real time; according to the operation data and the environment data, a corresponding early warning threshold is matched according to a preset threshold adjustment rule; obtaining one or more of the current transformer temperature, the current sudden change rate or the current vibration parameter as a target parameter; calculating the real-time deviation degree of the target parameter relative to the early warning threshold value, and monitoring the change rate of the target parameter; and when the deviation degree and the change rate of the target parameter meet a preset condition, generating a risk early warning signal of a corresponding level. The operation data and the environment data of the transformer are collected in real time, the early warning threshold value is dynamically adjusted according to the preset threshold value adjusting rule and the operation data and the environment data, and the early warning threshold value can adapt to different operation environments and load conditions.

The invention relates to a thermal control method and device, and relates to the technical field of flow battery energy storage, and the method comprises the steps: obtaining the working mode information of a flow battery and the temperature information of a plurality of preset positions, the preset positions at least comprise a galvanic pile liquid inlet pipeline, a galvanic pile liquid outlet pipeline, a prefabricated cabin, a storage tank, a magnetic drive pump and a converter; determining an application scene of the flow battery according to the working mode information and the temperature information; and controlling a cooling liquid shunting module to adjust a distribution path of cooling liquid in a cooling liquid loop so as to adjust the flow battery to a thermal control working condition corresponding to the application scene, the heat control working condition comprises a heating working condition started when the external environment temperature of the prefabricated cabin is lower than a first environment temperature threshold value, a refrigeration working condition started when the external environment temperature of the prefabricated cabin is higher than or equal to a second environment temperature threshold value, and a heat recovery working condition started when the working mode is switched.

The invention discloses a flexible direct-current transformer valve side partition plate system supporting strip fixing structure, and relates to the technical field of flexible direct-current transformer equipment, the flexible direct-current transformer valve side partition plate system supporting strip fixing structure comprises a partition plate system main body, the partition plate system main body is arranged in an ascending flanged base, and the partition plate system main body comprises an abutting part; the fixing assembly comprises a supporting strip and a locking assembly, the supporting strip is arranged between the partition plate system body and the ascending flanged base, the supporting strip is fixedly connected with the ascending flanged base through the locking assembly, the supporting strip comprises a wedge part, and the wedge part is matched with the abutting part in a friction abutting mode; according to the flexible direct current transformer valve side partition plate system supporting strip fixing structure, the supporting strip is arranged between the partition plate system body and the ascending flanged base, and the wedge part of the supporting strip abuts against the abutting part of the partition plate system body, so that tight supporting installation of the partition plate system body relative to the ascending flanged base is achieved, and the vibration influence generated in the transportation process is overcome.

The invention discloses a trapezoidal wave control method of a double-active-bridge direct-current transformer and related equipment, and relates to the technical field of direct-current transformers. In the double-active-bridge direct-current transformer, the first side of a first active bridge is electrically connected with a first direct-current port, the first end of the second side of the first active bridge is electrically connected with the first end of an auxiliary inductor, and the second end of the auxiliary inductor is electrically connected with the first end of a primary winding of an isolation transformer. The second side of the first active bridge is electrically connected with the second end of the primary winding of the isolation transformer; a secondary winding of the isolation transformer is electrically connected with a first side of a second active bridge, and a second side of the second active bridge is electrically connected with a second direct current port; the method comprises the following steps: controlling an inner phase shift angle of a first active bridge to be a first main phase shift angle, and controlling an inner phase shift angle of a second active bridge to be a second main phase shift angle; the difference value between the second main phase shift angle and the first main phase shift angle is a preset auxiliary phase shift angle. According to the embodiment of the invention, the operation reliability and efficiency of the double-active-bridge direct-current transformer can be improved.

The invention discloses a full-direct-current offshore wind power system zero-voltage ride-through method, equipment and a medium, and relates to the field of full-direct-current offshore wind power. The objective of the invention is to solve the problem that a receiving-end converter station cannot transmit power when a land AC power grid breaks down. When the high-voltage direct-current voltage of the offshore direct-current transformer exceeds the first preset threshold value, the medium-voltage direct-current voltage control of the offshore direct-current transformer is switched to the high-voltage direct-current voltage control, so that the offshore direct-current transformer absorbs power from a high-voltage direct-current link; when the medium-voltage direct-current voltage of the fan direct-current transformer exceeds a second preset threshold value, the fan direct-current transformer is switched from low-voltage direct-current voltage control to medium-voltage direct-current voltage control, so that the fan direct-current transformer can absorb power from the low-voltage direct-current voltage side through a fan grid-side direct-current transformer; and when the low-voltage direct-current voltage of the offshore direct-current transformer exceeds a third preset threshold value, the brake resistor is activated to dissipate surplus power until the low-voltage direct-current voltage is lower than a fourth preset threshold value.

The utility model belongs to the technical field of lightning protection current transformers, and particularly relates to an energy storage current transformer with a lightning protection module, which comprises a current transformer shell, a connecting seat connected to the outer side of the current transformer shell, a lightning protection assembly connected to the current transformer shell, and a lightning protection device connected to the inner side of the current transformer shell, the surge protector and the lightning protection device are arranged on the inner side of the converter shell, the surge protector and the lightning protection device are connected with an external grounding system through a grounding wire, the movable ventilation part assists in air exhaust and heat dissipation of the interior of the converter shell, the lightning protection device is matched with the grounding wire, and when lightning stroke occurs, lightning impulse energy is absorbed and discharged by the grounding wire through the external grounding system. And meanwhile, the surge protector works, so that the possibility that other devices in the box body are damaged when the lightning protection device generates an arc spraying phenomenon is reduced.

The invention relates to the technical field of wireless power transmission systems, and provides a method and equipment for estimating a coupling coefficient in a wireless power transmission system, and a transmitting end of the system comprises a converter used for converting direct current into alternating current with target power; the resonance circuit is used for converting the alternating current into magnetic energy; the processor is used for applying current disturbance to the converter, acquiring the damping frequency of the current at the input end of the converter after the current disturbance is introduced, and taking the damping frequency as the natural frequency of the wireless power transmission system; and calculating the ratio of the natural frequency to the resonant frequency of the wireless power transmission system, and determining the set multiple of the ratio as the coupling coefficient of the wireless power transmission system. According to the embodiment of the invention, the coupling coefficient of the wireless power transmission system can be quickly estimated at low cost.

The utility model provides photovoltaic energy storage bidirectional converter equipment, which relates to the technical field of converters, and comprises a fixed base and a converter body, the side surface of the converter body is provided with heat dissipation holes, the lower surface of the converter body is fixedly provided with convex blocks, the side surface of the fixed base is provided with convex grooves, and the convex grooves are fixedly arranged on the lower surface of the converter body. And a mounting plate is slidably connected into the fixed base. According to the utility model, the crank is rotated to drive the bidirectional screw rod to rotate, so that the moving block slides along the sliding rod, the mounting plate is pushed to move, the pin rod on the side surface of the mounting plate is inserted into the pin hole on the side surface of the convex block, and the magnet A and the magnet B are matched to attract each other, thereby realizing stable fixation of the converter body and the fixed base and facilitating installation and disassembly of the converter body; and the filter screen is arranged in the mounting frame on the side surface of the converter body, so that dust and sundries can be effectively prevented from entering the converter body through the heat dissipation holes, and internal electronic components are protected.

The application provides a kind of air conditioning unit rapid test method, device and medium based on current transformer.The method comprises: obtaining standard current value and detector type of current transformer group;Based on the standard current value, the current transformer group is calibrated before test;Respectively when vehicle is powered off and powered on, control current transformer group to collect three-phase current information of each electrical element in air conditioning unit at the same time, obtain first receiving voltage, first detection current, second receiving voltage and second detection current, and then obtain the target conversion formula corresponding to the detector type;Control current transformer group to collect real-time test data in the process of vehicle operation, and obtain target test result according to target conversion formula and real-time test data.The application can optimize the measurement process of three-phase current by combining the parameters of vehicle in the process of power off, power on and actual operation, improve the accuracy of test result, and is simple to operate and easy to implement.

The utility model discloses a compact direct-current transformer container, which belongs to the technical field of direct-current transformers and is characterized in that a low-voltage cabinet is arranged on the left side in the container, a high-voltage cabinet is arranged on the right side in the container, a direct-current transformer valve group I is arranged on one side close to the low-voltage cabinet in the container, and a direct-current transformer valve group III is arranged on one side close to the high-voltage cabinet in the container; a direct-current transformer valve group II is arranged between the direct-current transformer valve group I and the direct-current transformer valve group III; a first cabinet door is arranged at the left end of the outer surface of one side of the container, a third cabinet door is arranged at the right end of the outer surface of one side of the container, the first cabinet door corresponds to a low-voltage cabinet in the container, the third cabinet door corresponds to a high-voltage cabinet in the container, and a plurality of second cabinet doors are arranged between the first cabinet door and the third cabinet door at intervals and correspond to direct-current transformer valve groups respectively. According to the utility model, the cabinet doors correspond to the positions of the devices, the devices are convenient to disassemble and assemble, the devices are convenient to maintain by personnel, the high-voltage cabinet and the direct-current transformer valve group are arranged in the container to realize integral assembly and disassembly, and the occupied space is reduced.

The invention relates to the technical field of converters, in particular to a power dispatching system based on a multi-level direct current chopping technology, which comprises a flux linkage trend analysis module, a duty ratio constraint module, a standby unit evaluation module and a path synchronization coordination module. According to the method, the power integral curve is constructed in real time, the flux linkage increment trend is analyzed, the relevance between the flux linkage direction and the current change is dynamically judged, the duty ratio amplitude limiting range is adjusted in combination with the exponential smoothing prediction model, and phase compensation correction is executed, so that the dynamic response capability of the system is remarkably improved; a sliding standard deviation algorithm is adopted to screen a standby unit group and analyze a current fluctuation coefficient, linear regression is combined to process a temperature change trend, the anti-interference capability of the system is enhanced, a dynamic time warping algorithm is adopted to calculate a phase offset and construct a voltage difference vector, accurate synchronous control of a multi-level architecture is realized, and the stability of the system is improved. Harmonic content and energy loss are effectively reduced, electric energy conversion efficiency and equipment operation stability are improved, and the service life of a power device is prolonged.

The invention discloses a direct current transformer soft start method and related equipment, and relates to the technical field of direct current transformers. The direct-current transformer comprises a full-bridge inverter circuit composed of a first half-bridge and a second half-bridge. The soft start method of the direct-current transformer comprises the following steps: in a soft start stage of the direct-current transformer, in response to a full-bridge inverter circuit in a target switching period, controlling a sign symbol of an inner phase shift angle between a first half bridge and a second half bridge as a first symbol; in response to the full-bridge inverter circuit being in the next switching period of the target switching period, adjusting the sign symbol of the internal phase shift angle between the first half-bridge and the second half-bridge as a second symbol; wherein the positive and negative of the first symbol and the positive and negative of the second symbol are opposite, and the target switching period is any switching period in the soft start stage. According to the embodiment of the invention, the turn-off stress of the device can be effectively balanced, and the improvement of the reliability of the device of the direct-current transformer and the improvement of the starting speed of the system are facilitated.

The application relates to a direct-current transformer valve hall arrangement structure which adopts the technical scheme that: a direct-current transformer valve hall arrangement structure is characterized in that the valve hall is internally arranged with positive and negative electrode valves of a direct-current transformer; one side of the valve hall is a low-voltage direct-current incoming line end; the other side is a high-voltage direct-current incoming line end and a common incoming line end; and each incoming line end is connected with an external device through a wall or floor sleeve at different positions of the valve hall. The positive and negative electrode valves of the direct-current transformer are arranged in the valve hall, the arrangement is reasonable and compact, the space utilization rate is high, and the valve hall space is saved.

The invention relates to a circuit arrangement (2) for emergency shutdown of a standard insulation monitoring of an ungrounded power supply system (4) upon detection of a ground fault, having a standard insulation monitoring device (10) coupled to an active conductor (L1, L2, L3) of the power supply system (4) via each coupling branch (12) on the network side or to a neutral point (S) of the power supply system (4) via a coupling branch (12) and connected to a ground (PE) on the ground side via a ground branch (14). The circuit arrangement (2) comprises an AC / DC-sensitive measuring current transformer (20) for detecting a fault current at the active conductor (L1, L2, L3) in the coupling branch (12) or at the neutral point (S) in the coupling branch (12) on the network side or in the ground branch (14) of the insulation monitoring device (10) on the ground side, an evaluator (30) for evaluating whether the fault current exceeds a fault current threshold value, and a tripping device (40) for switching off the power supply system (4).

The application discloses a kind of calibration devices, it is related to test technical field, calibration device includes voltage source, current source, switching circuit module and detection circuit, voltage source is used to output calibration voltage;Current source is used to output calibration current;Switching circuit module one end is electrically connected with voltage source, current source, the other end of switching circuit module is used to be electrically connected with the equipment to be measured;Switching circuit module is used to switch the connection of voltage source and the equipment to be measured on, or switching current source and the connection of the equipment to be measured on;Detection circuit is electrically connected with the equipment to be measured, for detecting the actual voltage of equipment to be measured when voltage source and the equipment to be measured connection on, to carry out voltage calibration to equipment to be measured according to calibration voltage and actual voltage;Actual current of equipment to be measured is detected when current source and the equipment to be measured connection on, to carry out current calibration to equipment to be measured according to calibration current and actual current.The output current voltage of calibration current transformer and other equipment to be measured.

The invention discloses a control method, system and device for misoperation locking of a high-voltage direct-current power transmission system, and relates to the technical field of high-voltage direct-current power transmission, and the control method comprises the steps: reading a direct-current voltage value, measured by a control protection device, of the high-voltage direct-current power transmission system; if the direct-current voltage value is smaller than the starting voltage value of the low-voltage current-limiting protection, whether starting of the low-voltage current-limiting protection is caused by abnormal measurement after short-time voltage loss of a low-voltage arm of the direct-current transformer is judged; if the judgment result is that the starting of the low-voltage current-limiting protection is caused by the abnormal measurement after the short-time voltage loss of the low-voltage arm of the direct-current transformer, executing the regulation control of the low-voltage current-limiting protection; or if the judgment result is that the starting of the low-voltage current-limiting protection is not caused by the abnormal measurement after the short-time voltage loss of the low-voltage arm of the direct-current transformer, shielding the regulation control of the low-voltage current-limiting protection. The problem that short-time voltage loss of a low-voltage arm of a direct-current voltage divider of the high-voltage direct-current power transmission system is caused by lightning stroke disturbance, and then direct-current misoperation locking of the high-voltage direct-current power transmission system is caused is solved.

The invention provides a network construction converter cluster overload capacity improving method and system based on cooperative regulation and control, and belongs to the technical field of network construction converters, and the method comprises the steps: solving a PWM optimal phase by taking a total grid-connected current harmonic current as a rigid constraint and taking a minimum converter single-machine current harmonic current as a target at a pre-overload operation stage; in an overload transient operation stage, a reference value of a current inner ring in a dq coordinate system is generated based on a voltage ring, and then an effective value of a reference current is calculated; calculating an adjustment amount of the switching frequency based on a change in the effective value of the reference current; and in the overload steady-state stage, clustering all the adjustment amounts of the switching frequencies of the obtained network construction converter cluster, optimizing the PWM phase of each group after clustering to obtain the optimal phase of each group, calculating the phase additional value of each group based on the optimal phase, and adding the calculated phase additional value and the optimal phase in each group to obtain the overload steady-state current transformer. And finally obtaining the phase value of each converter, and sending the phase value to each converter.

The application discloses a photovoltaic direct-current step-up transformer topology structure and a control method thereof in the field of direct-current transformers, and the topology structure is composed of three-level half-bridge modules, two-level half-bridges, transformer leakage inductance L, a transformer T and full-bridge rectifier modules; the three-level half-bridge modules are connected in parallel to form a low-voltage direct-current end, and the full-bridge rectifier modules are connected in series to form a high-voltage direct-current port. The application can effectively reduce the voltage stress and the current stress of the switching device by inputting the multiple three-level half-bridge modules in parallel; the control mode adopted can realize ZCS turn-on and turn-off of the two-level bridge arms and also can reduce the current stress of the device, improve the reliability of the direct-current transformer and reduce the cost and the loss of the direct-current transformer.

The invention provides a direct-current transformer starting and stopping control method, system and device and a medium, and the method comprises the steps: carrying out the safe pre-charging of a capacitor through a hierarchical control strategy, and completing the starting of a high-voltage side and a low-voltage side; and quickly and safely discharging the voltage of the energy storage capacitor in a shutdown stage based on a distributed energy release scheme of an internal resistor, and completing shutdown control. Through a hierarchical control strategy and multi-stage self-adaptive charging of a high-voltage side, capacitor voltage balance and current limiting requirements can be considered in a starting stage; based on a distributed energy release scheme of an internal resistor, rapid and safe release of the voltage of an energy storage capacitor in an outage stage is realized, and the problems that single-stage charging is mostly adopted for high-voltage side starting, capacitor voltage balance and current limiting requirements are not considered, and an outage discharge scheme lacks adaptation to alternating-current and direct-current coupling characteristics, resulting in an energy feedback risk are solved.

The present disclosure provides a converter, a high-voltage direct current transformer, and a control method. The converter includes a series valve group and a switched capacitor valve group connected in parallel. The series valve group includes multiple valve string bridge arms connected in parallel, and each valve string bridge arm includes one or more first power switch modules connected in series. The switched capacitor valve group includes one or more second power switch modules connected in series. The switched capacitor valve group provided by the present disclosure reduces switching loss in the series valve group, and has high efficiency.

An attention mechanism adjustment method based on attention scores, applicable to Transformer models, is provided. The method includes: for the current Transformer block of the Transformer model, obtaining query matrix, key matrix, and value matrix based on the input sequence; using the self-attention module to generate multiple attention score matrices corresponding to multiple attention heads; before executing the softmax function, performing cross-head column-wise aggregation operation on the attention score matrices to obtain a token importance vector; comparing importance scores with the trained importance score threshold to determine if pruning is needed; executing pruning operations on target tokens that need pruning to obtain pruned attention score matrices; performing softmax function operations on the pruned attention score matrices to obtain a pruned attention probability matrix, where the probability values of the pruned tokens are zero.

The application provides a variable current transformer variable disturbance impedance measurement method. A variable-amplitude disturbance signal is injected into the variable current transformer during impedance measurement, and the impedance and phase characteristics of the variable current transformer are determined based on current responses and voltage responses under different amplitude disturbances. The difference between the current impedance and phase characteristics and the previous impedance and phase characteristics is taken as an iteration end condition, so that the influence of the nonlinear behavior of the variable current transformer can be basically overcome, the impedance detection accuracy can be effectively ensured, and accurate data reference for subsequent operation and maintenance of the variable current transformer is provided.