453 results about "Current range" patented technology

The invention discloses a method for evaluating the bearing time of an internal fault of large oil-filled main equipment, and belongs to the technical field of relay protection of oil-filled main equipment of a power system. Obtaining a plurality of fault currents in the internal fault current range of the oil-filled main equipment; establishing a three-dimensional geometric simulation model and a grid model of the oil charge main equipment; calling a transient pressure-based solver, simulating a turbulence phenomenon and an oil pressure rise phenomenon of the oil-filled main equipment under a fault current condition, judging whether the oil-filled main equipment is broken or not, and obtaining allowable fault bearing time of the oil-filled main equipment under different fault currents; and establishing a neural network model for mapping the fault current and the allowable fault withstanding time through a convolutional layer, a pooling layer and a full connection layer in the convolutional neural network, so as to evaluate the allowable fault withstanding time of the oil-filled main equipment. And the fracture and failure phenomena of the oil-filled main equipment in a high-stress state are accurately captured, so that a quantitative method which is more accurate than a traditional empirical method is provided for evaluating the fault bearing time of the oil-filled main equipment.

The invention relates to a negative-wear super-wear-resistant current-carrying friction pair material which is a conductive lubricating film which is constructed in situ and stably exists under a current-carrying friction condition, and the current-carrying friction pair material is composed of Ga-based liquid metal, a Mo coating and an Al alloy bolt. Through cooperation of friction pair materials, a friction interface reaction is adjusted to generate a conductive lubricating film, and excellent lubricating and wear-resisting properties are achieved; in a large voltage and current range, the average friction coefficient is always maintained to be 0.25 or below, the existence of the lubricating film enables the surface to present negative wear, and the average negative wear rate is 1.28 * 10 <-6 > mm < 3 > / Nm or above. The obtained material is suitable for application in the field of electric contact industry and provides lubrication and wear protection for the surfaces of mechanical parts.

The invention provides a current measuring circuit which comprises a micro-control unit and at least two measuring range circuits, and each measuring range circuit comprises a resistor, an MOS tube and an operational amplifier. The resistor of the previous measuring range circuit is connected in series with the resistor of the next measuring range circuit, the resistor of the first measuring range circuit is connected with power supply equipment, and the resistor of the last measuring range circuit is connected with a load to be measured; the micro-control unit is used for traversing the output voltage of the operational amplifier of each range circuit in sequence; if it is determined that target voltages on the two sides of a resistor of the measuring range circuit are smaller than a preset threshold value based on the output voltage, target current of a to-be-measured load is determined based on the output voltage and the resistance value of the resistor; and if the target voltage is not less than the preset threshold value, continuing to traverse the output voltage of the operational amplifier of the next range circuit. According to the technical scheme of the invention, the current measurement circuit meets the measurement requirements of a plurality of current ranges, the current ranges can be automatically switched, and the current output is not interrupted.

The invention relates to a measuring range dynamic adjusting method based on amplitude parallel estimation, which comprises the following steps of: (1) acquiring N current signal sampling points at a sampling rate fs, and calculating the amplitudes of the maximum N / 4 sampling points in the N sampling points in parallel; (2) storing N / 4 sampling points and the corresponding measuring range interval A; (3) continuously carrying out k times of signal sampling to obtain k groups of range interval sets {A1, A2,..., Ak}, and selecting the latest four groups of range intervals to carry out combined judgment; (4) if the four groups of measuring range intervals are consistent, keeping the current measuring range; if a wide-range interval occurs in the last two groups, switching to a wide range; and (5) carrying out trend estimation based on nearly five actual measuring range intervals. According to the invention, the key problem of the intelligent monitoring system in a high dynamic range signal monitoring scene is solved, the intelligent monitoring system can accurately judge the signal range and quickly adjust the range, and the loss of effective signals is reduced.

The invention discloses a V / I source system with a wide voltage and current range. The V / I source system comprises a power amplifier U1, a parameter measuring unit, a compensating circuit, a current sampling circuit, a voltage sampling circuit, a positive power supply module, a clamping circuit and a mode selector, the positive power supply module is connected with the positive power supply end of the power amplifier U1; the parameter measuring unit is provided with a plurality of channels for respectively setting the output voltage / output current of the power amplifier U1 and the clamping voltage / clamping current of the clamping circuit and adjusting the output voltage of the positive power supply module; the compensation circuit can adapt to different capacitive loads so as to be used for adjusting the establishment time of the output voltage / output current of the power amplifier U1, and the output end of the power amplifier U1 supplies power to the DUT; the method is excellent in performance, the test quality can be improved, and the test cost is reduced.

The invention provides an intelligent wire harness adaptive control method and system, and the method comprises the steps: S2, extracting a corresponding current range and a communication protocol from an output mode library according to an equipment type judgment result, and determining an initial output parameter; s4, executing the adjusted output parameters through a low-power-consumption communication module, obtaining equipment operation state data, and judging whether the real-time operation requirement is met or not; s6, after the pre-adjustment parameters are executed, equipment response data and energy consumption data are obtained, and whether system overload or power consumption exceeding exists or not is judged; s8, updating the equipment feature database and the output mode library according to the adjusted operation configuration, and obtaining updated collaborative performance indexes and energy consumption indexes; and S9, if the collaborative performance index and the energy consumption index do not reach the performance threshold, repeatedly executing the combined optimization process of the dynamic adjustment algorithm and the feature analysis algorithm. According to the invention, high-efficiency cooperation and energy consumption optimization of the wire harness and the intelligent equipment are realized.

The invention discloses a self-adaptive quick charging protection method and system for mobile equipment, which are used for adaptively adjusting charging current and a charging stage so as to prolong the service life of a battery. The method comprises the following steps: acquiring electrochemical impedance spectroscopy data of the battery, wherein the electrochemical impedance spectroscopy data is used for being combined with the cycle index and the capacity attenuation factor of the battery to evaluate the aging degree of the battery; determining a charging current in a pre-charging stage according to an aging degree evaluation result of the battery; when the real-time voltage of the battery reaches a constant-current charging voltage threshold value, the charging current is adjusted according to the real-time temperature of the battery so as to be switched to a constant-current charging stage; when the real-time voltage of the battery reaches a constant-voltage charging voltage threshold value, the charging current is secondarily adjusted through current pulse optimization so as to be switched to a constant-voltage charging stage, and the constant-voltage charging voltage threshold value is larger than a constant-current charging voltage threshold value; and when the battery capacity of the battery reaches a preset full-load threshold value, adjusting the charging current to be within a trickle charging current range so as to switch to a trickle charging stage.

The invention discloses a parameter identification and table look-up optimization-based PMSM current loop PI parameter adaptive control method. The method comprises the steps of 1, constructing a current controller PI parameter adaptive control system; 2, the data acquisition module acquires data of the permanent magnet synchronous motor in real time; 3, dynamically updating full-speed-domain inductance parameters of the permanent magnet synchronous motor by a motor parameter identification module to obtain a motor inductance curve; 4, a motor parameter identification module divides a motor operation interval into at least six working conditions, and determines a current range and an inductance parameter value of each working condition; 5, a model-based PI parameter setting unit performs setting according to the inductance parameter value to obtain an initial PI parameter; a rule-based PI parameter optimization unit performs optimization according to the initial PI parameter to obtain an optimal PI parameter, and generates a global PI control table; and 6, the current loop controller queries the optimal PI parameter according to the real-time current value matching working condition, and quickly updates the controller parameter to realize self-adaptive control. The method has the advantages that the current loop PI parameters in the full-speed domain can be rapidly and accurately adjusted.

The invention relates to the technical field of lasers, and discloses a laser temperature adjusting method and device, and the method comprises the steps: determining a second thermistor temperature based on a predetermined temperature compensation coefficient, a first environment temperature, a second environment temperature and a first thermistor temperature, the temperature of the thermistor at the second environment temperature is adjusted to be the second thermistor temperature; wherein the process of predetermining the temperature compensation coefficient comprises the following steps: carrying out a wavelength change test on the laser chip at a first preset temperature and within a preset current range, and determining wavelength change data corresponding to the laser chip; and calculating according to the first relation of the laser chip wavelength along with the change of the environment temperature, the wavelength change data, the temperature tuning coefficient and the test environment temperature change data to obtain a temperature compensation coefficient. Therefore, a temperature compensation coefficient is introduced to counteract the influence of ambient temperature fluctuation on the actual temperature of the laser chip, and the output wavelength stability of the laser is effectively improved.

The invention relates to power semiconductor device on-line monitoring and power electronic system control, in particular to a SiC MOSFET conduction current extraction circuit and method, high-frequency oscillation interference is effectively suppressed through a second-order passive RC filter circuit, a measurement error less than or equal to 1.5% is realized within a current range of 50A-300A in combination with an accurate mathematical model established by a depth symbol optimization algorithm, and the measurement accuracy is improved. The requirement of the intelligent gate driver on high-precision current feedback is met, and the measurement precision is remarkably improved; the pulse width direct analysis technology is adopted, a traditional active integrator and a digital decoding link are omitted, the system response delay is smaller than or equal to 500 ns, microsecond-level over-current protection can be supported, the response speed and the real-time performance are optimized, and the system safety in a high-frequency application scene is remarkably improved.

A control method for suppressing an overvoltage of the receiving end hybrid modular multilevel converter with full-bridge submodules and half-bridge submodules (F / HMMC) under the fault at the receiving-end alternating-current (AC) system of the hybrid high-voltage direct-current (HVDC) transmission system. After a short-circuit fault occurs in a receiving-end AC) system of the hybrid HVDC transmission system, an AC voltage drop is generated, and the effective voltage of the receiving-end AC bus at the current time is measured. Because the hybrid modular multilevel converter (MMC) is capable of actively decreasing the DC voltage for operation, on a premise of ensuring that its output current is always within a rated current range, a control manner of setting the reference DC voltage and making the reference DC voltage not greater than the effective voltage of the AC bus enables receiving end power to be sent out, thereby suppressing an overvoltage of the receiving-end F / HMMC.

A communication method includes: sending a first poll frame, where the first poll frame is for triggering ranging measurement in a first range-measurement cycle, the first poll frame further indicates a first parameter set that takes effect in the first range-measurement cycle, and the first parameter set includes one or more of the following parameters: a first narrowband physical layer (PHY) parameter, a first narrowband channel allow list, a first ranging block structure parameter, or a first ultra-wideband (UWB) multi-millisecond (MMS) ranging configuration parameter; and receiving a response frame of the first poll frame. According to the present disclosure, an initiator uses a poll frame to indicate a parameter set that takes effect in a current range-measurement cycle.

The invention provides a fault detection processing method and device for an uninterruptible power supply, and a controller, and the method comprises the steps: sampling the current of at least one to-be-detected sampling point in at least one to-be-detected fault loop in the uninterruptible power supply, and comparing the current with a corresponding fault current range; according to the method and the device, the fault circuit to be checked is detected to determine that a fault device causing current abnormity exists in the fault circuit to be checked, and the operation state of the rectifying and discharging multiplexing circuit is adjusted based on the fault switching device, so that the fault circuit where the fault switching device is located is cut off, the influence of fault current on the uninterruptible power supply is terminated in time, and the reliability of a power supply system is guaranteed.

The invention discloses a Si / SiC hybrid device switch control method based on load current range interval division. The method comprises the steps that the maximum bearable pulse current of a SiC MOSFET and the load current range of a hybrid device are acquired; dividing the load current range of the hybrid device into intervals E, F, G and H; wherein 0 < = E < the first current value; the first current value < = F < = the second current value; g is larger than the second current value and smaller than the maximum bearable pulse current of the SiC MOSFET; the maximum bearable pulse current H of the SiC MOSFET is greater than or equal to the maximum value of the load current range and less than the maximum value of the load current range; and when the load current of the hybrid device is in the intervals E, F, G and H, making the hybrid device work in a preset mode. The invention also discloses a Si / SiC hybrid device switch control system based on load current range interval division.

The invention relates to a sensor regulation and control method and a contact device, and belongs to the technical field of detection control, and the sensor regulation and control method comprises the steps: responding to a first trigger instruction of a user, and carrying out a self-adaptive range determination program; acquiring detection data of the sensor when a user uses the contact type equipment; wherein a sensor is loaded in the contact equipment; acquiring a data maximum value in the detection data within a preset time; determining a data maximum value in the detection data as a current range maximum value of the sensor; wherein the current range maximum value of the sensor is not greater than the actual range maximum value of the sensor; and regulating and controlling the contact type equipment based on the maximum value of the current measuring range of the sensor. In this way, the method can adapt to user requirements, so that the response interval of the sensor fits the use state (non-curing) of a user. Even different products of the same type can meet the requirement for consistency of the user through the regulation and control.

The embodiment of the invention provides a battery state detection method and device, and the method comprises the steps: obtaining historical charging data of a vehicle battery in a historical time period; data analysis is conducted on the historical charging data, multiple charging data fragments are intercepted from the historical charging data, and the multiple charging data fragments are used for representing data fragments for continuous charging of the vehicle battery within a preset charging current range; feature extraction is conducted on the multiple charging data fragments, charging feature data of the vehicle battery are obtained, and the charging feature data are used for reflecting the electric quantity change condition and the temperature change condition of the vehicle battery when charging is conducted on the target vehicle within the historical time period; the battery state detection model is used for processing the charging characteristic data, the battery state of the vehicle battery is obtained, and the battery state is used for representing whether the vehicle battery has the power shortage risk or not. The technical problem of low precision of predicting the health state of the vehicle battery in the prior art is solved.

A method of programming non-volatile memory cells comprising determining a target read current for respective ones of the memory cells based upon incoming data, associating respective ones of the memory cells with a respective one of a plurality of cell groups based upon the determined target read current for the respective memory cell being within a target read current range associated with the respective cell group, fast programming respective ones of the memory cells to a coarse target read current associated with the cell group to which the respective memory cell is associated, wherein the coarse target read current for respective ones of the cell groups is greater than the target read current range for the respective cell group, and then slow programming respective ones of the memory cells until the target read current determined for the respective memory cell is achieved.

The invention discloses a method and a device for rapidly detecting an optimal efficiency point of a variable frequency motor system, and belongs to the technical field of motor system detection. Selecting an initial test point, and obtaining a rough search range based on the initial test point; efficiency testing is carried out on each test point in the rough search range, the optimal efficiency of the current range is obtained, and whether the global optimal efficiency is updated or not is judged; if the global optimal efficiency is updated, obtaining a high-efficiency area based on the updated global optimal efficiency; carrying out fine mesh division on the high-efficiency region, and then testing each fine mesh test point; and if the variable quantity of the efficiency value meets the preset requirement, outputting the global optimal efficiency and the corresponding torque value and rotating speed value. According to the method, the torque and rotating speed range, the step length and the test point duration can be adaptively adjusted, and the search range and the convergence condition are allowed to be customized; the testing probability of a non-efficient working condition area is reduced, meanwhile, the testing precision of an efficient working condition area is remarkably improved, and the detection efficiency and precision are effectively optimized.

The invention provides a single-mode semiconductor laser failure assessment method and device and electronic equipment, and relates to the technical field of semiconductor lasers. The method comprises the following steps: acquiring an optical power current characteristic test curve of the failed single-mode semiconductor laser; determining an optical power parameter change trend of the failed single-mode semiconductor laser according to a preset optical power current characteristic standard curve and the optical power current characteristic test curve of the failed single-mode semiconductor laser; if the optical power parameter variation trend indicates that the optical power parameter in the working current range is zero, determining that the failure type is optical cavity surface catastrophe damage; and if the optical power parameter variation trend indicates that the optical power parameter in the working current range is non-linearly decreased, determining that the failure type is optical body material catastrophe damage, so that the failure type of the single-mode semiconductor laser can be judged through the optical power current characteristic test curve. The evaluation cost can be reduced, the evaluation efficiency is improved, and the accuracy of evaluation results is ensured.

A computer system determines a compensation current adapted to counteract at least parts of a charge equalization current expected to be generated by an activation of an additional battery pack in parallel connection with one or more currently activated battery packs. The compensation current is determined as a current range between a lower and upper compensation current limits. The lower limit is based on a voltage of the additional battery pack, and a voltage and impedance of the currently activated battery packs. The upper limit is based on a maximum discharge ability of a system powered by the currently activated battery packs, a maximum discharge ability of the currently activated battery packs, a voltage and impedance of the additional battery pack, and a voltage and impedance of the one or more currently activated battery packs.

A current measurement system, comprising a plurality of parallel sensing circuits, each sensing circuit configured to measure a respective range of voltage corresponding to a current through a load, wherein each sensing circuit is triggered to initiate measurement of a voltage across the load in response to a buffer current through a common buffer reaching a respective threshold, a buffer circuit for inputting a virtual ground voltage or a virtual ground current to the load and to the plurality of parallel sensing circuits, the virtual ground voltage corresponding to the voltage across the load or the current through the load, and a processor coupled to the plurality of parallel sensing circuits, wherein the processor is configured to combine data representing voltage measurements from the plurality of parallel sensing circuits to determine the current through the load.

The invention relates to the technical field of smart home, and discloses a range hood parameter synchronization control method and device applied to multiple associated scenarios, and the method comprises the steps: judging whether there is an associated family scene in a scene when a user uses a range hood in a new family scene; if yes, the scene difference degree of the family scene and the associated family scene is compared to obtain scene difference degree information; according to the scene difference degree information, adjusting a range hood parameter control model corresponding to the associated family scene to obtain a range hood parameter control model corresponding to the family scene; and based on the range hood parameter control model, generating a current range hood control parameter corresponding to the range hood in the family scene. It can be seen that when the user uses the range hood in the new environment, the generation efficiency of the range hood parameter control model can be improved, the obtaining efficiency and timeliness of the range hood control parameters matched with the new environment can be improved based on the rapidly generated model, and therefore the range hood control efficiency and the range hood control reliability can be improved.

The invention belongs to the field of electric energy meters, particularly relates to an automatic compensation calibration method for electric energy metering errors of an electric energy meter, and aims to solve the technical problems that a CORDIC algorithm is difficult to give consideration to efficiency and precision and an existing compensation method is difficult to correct multi-dimensional nonlinear errors under wide temperature and wide flow. Outputting an uncorrected x-axis component and a final accumulated phase angle, wherein the improved CORDIC iterative operation comprises M times of coarse rotation iteration and P times of fine rotation iteration; s2, performing amplitude correction on the uncorrected x-axis component to obtain a corrected instantaneous current amplitude; and S3, performing reconstruction by using the corrected instantaneous current amplitude and the final accumulated phase angle to obtain a corrected instantaneous current value, multiplying the corrected instantaneous current value by the instantaneous voltage value to obtain instantaneous active power, and performing accumulated integration on the instantaneous active power to obtain a compensated and calibrated electric energy value. According to the invention, high-precision metering performance of the electric energy meter in a wide current range and a wide temperature change range can be ensured.

The invention discloses a construction site distribution current wide-range measurement circuit and a measurement method thereof. The circuit comprises a current-to-voltage circuit (1), a voltage amplification circuit (2) and a current range control module (3). A first resistance switching module (5) is arranged in the current-to-voltage circuit (1), and the first resistance switching module (5) adjusts multiple conversion between an input current and an output voltage by switching resistance values; the voltage amplification circuit (2) is provided with a second resistance switching module (6), and the second resistance switching module (6) adjusts the amplification factor of the output voltage by switching resistance values; according to the invention, the current signal is amplified according to the required proportion through the multiple-adjustable current-to-voltage circuit and the voltage amplification circuit, so that the accurate measurement of the current is realized.

The invention provides an audio power amplifier device and a loudspeaker, and relates to the technical field of power amplifiers, the audio power amplifier device comprises an audio power amplifier, and a current detection circuit is used for detecting a power tube current of the audio power amplifier and outputting a corresponding current detection signal; the temperature detection circuit is used for detecting the temperature of a power tube of the audio power amplifier and outputting a corresponding temperature detection signal; the control circuit is connected with the controlled end of the audio power amplifier; the control circuit is used for determining a current threshold value according to the temperature detection signal; the control circuit is also used for controlling the working state of the audio power amplifier according to the current threshold and the current detection signal; the change trend of the temperature and the current threshold of the power tube is that the lower the temperature of the power tube is, the larger the current threshold is. According to the invention, the output current range of the power amplifier can be dynamically adjusted, so that better tone quality experience is realized.

The present disclosure provides a control circuit and a control method of a bistable permanent magnet mechanism. The control circuit includes five switches, a diode and a control unit for controlling the five switches to be turned on and turned off. The control circuit enables the positive and the negative of the current passing through the coil to be adjustable at any time and avoids load breaking, without a complicated design of a driving circuit, thereby reducing the cost. It can also realize PWM control, adapt to a larger current range and different bistable permanent magnet mechanisms, and has a wide range of application scenarios.

The invention discloses a cable-beam combined structure 1 / 2 subharmonic resonance vibration reduction method. The method comprises the following steps that S1, the optimal damping force needed by a cable in the current motion state is obtained according to a time-lag vibration reduction rule; s2, calculating a target current required by the MR damper according to the obtained optimal damping force; s3, mapping the target current to a current interval which can be actually applied by the MR damper by using a mapping algorithm to obtain a mapping current; s4, adjusting individual overlarge mapping current to obtain applied current; and S5, current is applied to the MR damper so as to control the cable-beam combined structure. According to the method, the optimal damping force and the target current are accurately calculated, and the time-delay selection rule is combined, so that 1 / 2 subharmonic resonance can be accurately inhibited, the vibration amplitude of the cable-beam composite structure under the specific frequency is effectively reduced, the fatigue damage risk of the structure is reduced, and the service life of the bridge is prolonged.

This utility model relates to the field of electrical energy detection technology, and proposes a high-current electrical energy detection device with closed-loop control function. The device includes: a programmable power source module, including an output drive unit for outputting current, voltage signals, and waveforms within a large current range; a standard measurement module connected to the output drive unit for detecting the current, voltage signals, and waveform parameters output by the output drive unit; a waveform sampling module connected to the output drive unit for sampling the waveform output by the output drive unit; a closed-loop control module bidirectionally connected to the programmable power source module and the waveform sampling module for adjusting the current, voltage signals, and waveforms; and an external device detection interface connected to the output terminal of the output drive unit for connecting different types of high-current metering devices. This utility model solves the problems of measurement error superposition, unstable output, and insufficient measurement range in traditional detection devices.

The invention discloses a fan moving blade adjusting and calibrating method and a fan. The method comprises the following steps: firstly, determining a target area of a fan blade corresponding to a performance curve of a target fan; a first current signal is sent to a proportional valve, and a hydraulic cylinder drives fan blades to rotate in the first direction; when the fan blade rotates to a first limit, a first target value of the displacement sensor is obtained; a second current signal is sent to the proportional valve, and the hydraulic cylinder drives the fan blades to rotate in the second direction; when the fan blade rotates to a second limit, a second target value of the displacement sensor is obtained; and determining a calibration current range of the fan blade according to the first target value and the second target value. According to the application, the adjusted fan objects are wide, and different from the debugging mode of an electric actuating mechanism, the application can meet the extreme condition of fan operation adjustment, when the oil station and the fan moving blade adjustment calibration device are completely powered off, the hydraulic cylinder cannot move, the blade keeps the adjustment opening degree, and the rapid change of the flow and the pressure of the fan is prevented.

A power supply that extracts power from the electromagnetic field surrounding an electrical cable of an electrical grid over a wide current range through the electrical cable. The power supply includes multiple power supply modules connected in parallel across the same input ferromagnetic core and across the same output capacitor. The power supply modules have different numbers of windings across the ferromagnetic core, and when the output voltage exceeds an allowable value for a particular power supply module, a short circuit is applied across the winding of each power supply module.