429 results about "Differential amplification" patented technology

The invention relates to the field of biomedical engineering, and discloses an embedded electroencephalogram signal collecting device and system.The device comprises a power management module, a plurality of electrode assemblies, a control module and a storage and communication module; through a control module designed by a system on chip SoC and a multi-electrode assembly in contact with intracranial nerves, the embedded electroencephalogram signal acquisition device which is in multi-level cooperation, supports user-defined sampling parameters and self-adaptive strategies and meets individual requirements of different focus monitoring scenes is constructed. High-precision distributed acquisition and self-adaptive processing of intracranial electroencephalogram signals are realized; a multi-electrode assembly is adopted, each assembly is provided with a plurality of contacts, the limitation of traditional single-point collection is broken through, different nerve areas are covered through the spatially distributed contact layout, and the focus positioning capacity is improved; the acquisition module effectively eliminates power supply ground wire interference and electromagnetic noise by using a differential amplification and common-mode rejection technology, and eliminates power frequency interference by combining band-pass and notch filtering to ensure the quality of an original signal.

This invention relates to a method and system for adaptive reclosing of single-phase AC transmission lines in wind power systems. The invention utilizes single-ended electrical quantity to determine the type of fault. After a fault occurs, a signal acquisition device is used to sample the voltage of the fault phase. The obtained voltage is subjected to short-time Fourier transform to extract the amplitude of the fundamental frequency voltage component, and then processed with differential amplification to construct a fault nature identification criterion. Combined with a sliding time window for fault identification, if it is identified as a permanent fault, the reclosing device is locked out; if it is identified as a transient fault, the fault disappearance time is calculated to determine the reclosing time and output the closing signal. This invention is designed for adaptive reclosing after a circuit breaker trips in wind power AC transmission lines.

The present application relates to the field of solution measurement, in particular to an electrode conductivity sensor conductivity measurement circuit and method, first, the AC excitation generation module generates an amplitude and frequency adjustable AC sine excitation signal under the control of the single-chip microcomputer; then the AC sine excitation signal passes through the precision resistor R0 and the conductivity cell of the electrode sensor to the system ground in turn; then the differential amplification circuit differentially amplifies the voltage between the precision resistor R0 and the electrode sheet of the conductivity cell; the amplified voltage signal is collected by the ADC, and then the voltage data is transmitted to the single-chip microcomputer; finally, the single-chip microcomputer can obtain the conductivity of the solution after the collected voltage data is operated. The present application directly collects the peak and valley voltage values of the AC signal, subtracts to obtain the amplitude of the AC signal, and does not need a rectification filter circuit to detect the amplitude of the AC signal, which can quickly respond to the change of the solution conductivity, eliminates the influence of common-mode interference factors, and simplifies the circuit design.

The invention relates to a micro-current detection system, which comprises a clamping current sampling unit, a current amplification conditioning unit, an analog-to-digital conversion unit and a controller, and is characterized in that the clamping current sampling unit comprises a plurality of clamping sampling circuits which are sequentially connected in series, and the first clamping sampling circuit and the last clamping sampling circuit are both used for being connected to a detected sensor; the current amplification conditioning unit comprises differential amplification conditioning circuits, the number of the differential amplification conditioning circuits is associated with the number of the clamping sampling circuits, and the differential amplification conditioning circuits are electrically connected to the clamping sampling circuits in a one-to-one correspondence manner; the analog-to-digital conversion unit comprises an analog-to-digital converter, and the analog-to-digital converter is electrically connected to all the differential amplification conditioning circuits; the controller is electrically connected to the analog-to-digital converter. According to the invention, real-time, precise, continuous and dynamic self-adaptive sampling can be carried out on the micro-current through the clamping current sampling unit, and the current amplification gain does not need to be adjusted by frequently switching a sampling resistor. Moreover, the collection noise can be effectively suppressed, and the signal-to-noise ratio is improved.

The invention discloses a gas concentration detection circuit and method based on differential measurement and reference compensation, and the circuit comprises at least one active gas sensitive element, the electrical parameters of which change along with the concentration of a target gas; the sensitivity of the reference gas sensitive element to the target gas is at least lower than that of the active gas sensitive element by a preset percentage threshold value; the active gas sensitive element and the reference gas sensitive element are connected in a differential pair form to form a differential signal generation unit; the differential amplification circuit is used for amplifying the differential signal output by the differential signal generation unit; the output signal of the differential amplification circuit is used for representing the concentration information of the target gas. According to the invention, environmental interference and baseline drift are directly and effectively suppressed from the hardware level, the stability and selectivity of gas concentration measurement are improved, and meanwhile, the holding circuit is simple in structure, low in cost and convenient for large-scale application.

The invention discloses a signal transmission circuit and system of an electronic mutual inductor and a working method, and belongs to the field of electric power protection and measurement and control. A voltage signal in the same proportion as the primary current signal is output to the voltage-current conversion circuit, and the voltage-current conversion circuit converts the voltage signal into a current signal I1 and outputs the current signal I1 to the constant-current voltage stabilizing circuit; the constant-current voltage stabilizing circuit generates a current signal I2, the current signal I2 supplies power to a pre-stage circuit after voltage stabilization, the current signal I2 and a current signal I1 are superposed to output a current signal I3 to the power supply and signal separation circuit, and the protection measurement and control device extracts the current signal I1 in the current signal I3 and converts the current signal I1 into a voltage signal to be collected. A voltage signal suitable for being collected by an AD chip is output through an active differential amplifier, and power is supplied to a constant-current voltage stabilizing circuit. The problems that signal attenuation is obvious and independent power supply is needed during long-distance transmission of the electronic transformer can be solved.

The invention provides a constant-power driving method of a light source, a light source driver and an air conditioning system, and the constant-power driving method comprises the steps: determining an equivalent voltage corresponding to the power of the current light source based on the working current and working voltage of the current light source obtained in real time; performing differential amplification processing on the equivalent voltage and the expected voltage to generate a constant power modulation instruction of the light source; the expected voltage is a constant voltage simulated according to the rated power of the light source; driving power of the light source is generated based on a constant power modulation instruction of the light source and a feedback adjustment instruction, the driving power is amplified by using a preset power amplification coefficient, the amplified driving power is used for driving the light source to emit light, and the feedback adjustment instruction is generated based on sampling feedback of the driving power of the amplified light source. The constant-power driving of the light source is adopted, so that the service life, the precision and the response speed of the light source are ensured.

The utility model discloses a background suppression photoelectric sensor realized based on double PD. The background suppression photoelectric sensor comprises an MCU control circuit, an LED drive circuit, an acquisition module, a target object, a differential amplification circuit, a voltage comparison circuit and a self-adaptive output circuit. The acquisition module is used for receiving reflected light signals of a target object and converting the reflected light signals, then the differential amplification circuit amplifies and converts PD signals received by the acquired signals, and then analog quantity signals are converted into pulse signals through the voltage comparison circuit, so that the MCU control circuit can be used for processing logic signals and modulating PWM signals. The LED driving circuit is arranged to drive the LED diode D6 to work; the background suppression photoelectric sensor realized by a photodiode PD1, a photodiode PD2, a differential amplification circuit, a voltage comparison circuit and an MCU control circuit adopts an automatic frequency conversion technology to solve the problem of optical crosstalk among multiple sensors, and is suitable for background suppression photoelectric sensing.

The invention discloses an automatic temperature compensation circuit and method based on a thermal flowmeter, and relates to the technical field of temperature compensation, and the compensation circuit comprises a constant current source module used for driving the thermal flowmeter; the Wheatstone virtual bridge arm is used for acquiring a changed digital-to-analog converter output voltage value output by the controller, and performing voltage conversion on a first voltage and a second voltage which are output on the thermal flowmeter due to the change of the external temperature according to the output voltage value to obtain a third voltage; the digital-to-analog converter is used for performing correction compensation on the third voltage according to the correction compensation value calculated by the controller; and the differential amplification module adopts a differential amplifier to amplify the third voltage and the fourth voltage output by the thermal flowmeter, and outputs a compensated flow signal. The compensating circuit is simple in structure and higher in reliability and precision, and compared with a digital potentiometer, the output value of the Wheatstone virtual bridge arm is changed by using the output value of the digital-to-analog converter, so that the adjusting resolution is higher.

The invention relates to the technical field of battery self-discharge testing, in particular to a zero-impedance-based battery self-discharge testing device and a zero-impedance-based battery self-discharge testing method. The battery self-discharge testing device comprises a connector module; the current detection unit comprises a sampling resistor Rsense and a differential amplification circuit, and the sampling resistor Rsense is connected in series in a current input loop; the differential amplification circuit is in bridge connection with the two ends of the Rsense of the sampling resistor and outputs a voltage signal proportional to the self-discharge current Idischarge current; the input end of the voltage detection unit is connected with the four-wire system voltage test terminal, and the open-circuit voltage VOCV of the battery to be tested is sampled in real time; the controllable voltage source module is used for outputting a dynamic compensation voltage Vapplied which is equal to the sum of VOCV and Idischarg * Rcircit, wherein the Vapplied is equal to VOCV + Idischarg * Rcircit; the controller module is used for calculating the real-time voltage drop of the total impedance Rcircuit of the circuit based on the VOCV and the Idischarge, and dynamically adjusting the output of the controllable voltage source, so that the terminal voltage of the battery to be detected is locked as the VOCV; and when the terminal voltage of the to-be-detected battery is stabilized within the range of VOCV + / -0.0001%, determining that the to-be-detected battery enters a constant potential mode, and continuously recording the current value until the current value is stable.

The invention discloses a seesaw type optical fiber end face weak force sensor which comprises a seven-core optical fiber, a seesaw type additive structure and an interference light beam. The seven-core optical fiber is composed of a central main fiber core and six symmetrically-distributed auxiliary fiber cores. The seesaw-type additive structure is composed of a short vertical beam, a vertical beam on a central main fiber core of the seven-core optical fiber and a cross beam connected to the vertical beam, and the whole structure is prepared through the two-photon polymerization technology of a femtosecond laser processing platform; the interference light beam is composed of two light beams in an interference cavity, wherein the lower surfaces of the left side and the right side of the seesaw-type additive structure are aligned with the end faces of two auxiliary fiber cores on the left side and the right side of the seven-core optical fiber. According to the invention, a two-photon polymerization technology is used to build an additive structure on the end face of the seven-core optical fiber, so that the sensing structure is small in overall size and is suitable for application in a limited space; the Fabry-Perot interferometers on the two sides of the sensing structure are connected in parallel to form an optical dynamic vernier structure, the sensitivity is improved through differential amplification of weak mechanical disturbance, and the anti-interference capability is enhanced through common-mode denoising.

A high-speed, low-noise laser signal detection apparatus, comprising a low-noise linear regulated power supply and a laser detection processing module. The low-noise linear regulated power supply (01-03) comprises an isolation unit (01), a voltage regulation and filtering unit (02), and a reference unit (03). The laser detection processing module (04-09) comprises a laser light signal detection input unit (05), a bias unit (04), a differential amplification unit (07), an active filtering unit (08), and an output interface unit (09). An output end of the voltage regulation and filtering unit (02) is connected to the reference unit (03) and the laser detection processing module (04-09). The reference unit (03) is connected to the bias unit (04) and is configured to provide a reference voltage to the bias unit (04). The bias unit (04) is configured to provide a bias voltage to the differential amplification unit (07). The differential amplification unit (07) comprises a multi-stage in-phase proportional differential amplification circuit, and the active filtering unit (08) comprises a multi-order active low-pass filter. According to the high-speed, low-noise laser signal detection apparatus, the detection bandwidth of a laser signal can be expanded, the signal-to-noise ratio of high-frequency pulse measurement can be reduced, and the anti-interference characteristics of a power supply can be improved.

The invention discloses a detection device and a detection system for harmonic oscillator capacitors of a hemispherical resonator gyroscope, and relates to the technical field of capacitor detection, the detection device comprises a signal detection circuit, a modulation compensation circuit, a differential amplification circuit and a control circuit, the signal detection circuit is connected with the output ends of the two harmonic oscillator capacitors; the modulation compensation circuit is correspondingly connected with two input ends of the signal detection circuit; the differential amplification circuit is correspondingly connected with two output ends of the signal detection circuit; the control circuit is configured to output modulation voltage to the two input ends of the modulation compensation circuit according to a voltage signal of the output end of the differential amplification circuit, and zero setting is carried out on voltage at the connecting positions of the two output ends of the modulation compensation circuit and the two input ends of the signal detection circuit. According to the invention, the modulation compensation circuit is adopted to enable the output ends of the two harmonic oscillator capacitors to work near zero voltage, the circuit has the characteristics of ultrahigh linearity, extremely low temperature drift, rapidness and stability, errors caused by power supply drift can be eliminated, and the detection precision is improved.

The invention relates to the technical field of analog integrated circuits, and discloses an LDO (Low Dropout Regulator) frequency compensation circuit based on a voltage-controlled current source, which comprises an input differential amplification module, a power regulation module, a frequency compensation module and a feedback voltage division module, and is characterized in that the output end of the input differential amplification module is electrically connected with the input end of the frequency compensation module; the frequency compensation module comprises a voltage-controlled current source and a compensation capacitor C1, the compensation capacitor C1 is matched with the voltage-controlled current source to adjust the loop frequency response, through a multi-stage current mirror and a Miller compensation network, pole distribution is optimized in a targeted mode, the Miller effect of the compensation capacitor C1 is matched, the dominant pole frequency can be actively lowered, a dominant pole is made to be away from a high-frequency area, and the loop phase margin is guaranteed; the self-excited oscillation is fundamentally suppressed, and the output voltage is stable and free of fluctuation.

Provided is a differential amplifier comprising: a first differential amplification circuit that has a first input terminal, a second input terminal, a first output terminal and a second output terminal which respectively output a first output signal and a second output signal; an RC filter that filters the first output signal and the second output signal and outputs them; a second differential amplification circuit that has a third input terminal and a fourth input terminal to which the first output signal and the second output signal filtered by the RC filter are respectively input and a third output terminal which outputs a third output signal; and a third amplification circuit that has a fifth input terminal to which the third output signal is input and a fourth output terminal which outputs a fourth output signal according to the third output signal.

The invention relates to a high-precision accelerometer signal pseudo-differential digital conversion circuit and a working method. The circuit comprises an I-V conversion circuit, a pseudo-differential amplification circuit and an AD conversion circuit. The I-V conversion circuit is used for converting a current signal output by an accelerometer into a voltage signal, filtering high-frequency interference and realizing impedance matching with the pseudo-differential amplification circuit so as to reduce signal distortion; the pseudo-differential amplification circuit is used for differentiating the ground and an input signal so as to reduce the influence of common-mode interference on the detection precision of the circuit, and adjusting the amplitude of an input voltage signal at the same time; and the AD conversion circuit is used for performing high-precision digital conversion on the input pseudo-differential voltage signal. According to the invention, I-V conversion with high common-mode noise suppression is realized, and high-precision voltage signal digital conversion is also realized.

The utility model belongs to the technical field of human body pulse detection, and discloses a pulse amplifying circuit based on a pressure sensor and a pulse signal acquisition system, and the circuit comprises the pressure sensor, a first-stage amplifying circuit, a second-stage amplifying circuit, a third-stage amplifying circuit, a fourth-stage amplifying circuit and a reference circuit, the signal input end of the first-stage amplification circuit receives an original pulse signal output by a pressure sensor and then outputs a differential amplification signal, the signal input end of the second-stage amplification circuit receives the differential amplification signal and then suppresses a common-mode signal and outputs a second amplification signal, and the signal input end of the third-stage amplification circuit receives the second amplification signal and then outputs the third amplification signal. The isolated direct current passes through a signal and outputs an alternating current signal in a following mode, a fourth-stage amplifying circuit receives the alternating current signal and then amplifies and filters the alternating current signal, and an amplified pulse signal is obtained and output. According to the utility model, the cost of the product is reduced, the circuit is simplified, the practicability is enhanced, and the pulse signal can be accurately measured.

The invention discloses a silicon carbide MOSFET parallel current sharing system and method for a pulse power supply, and belongs to the technical field of SiC MOSFET parallel current sharing, the system comprises a main power circuit connected with a plurality of SiC MOSFETs in parallel and an active driving circuit, when the SiC MOSFETs are turned on, a source inductor generates an induced voltage in direct proportion to the current rising rate, and when the SiC MOSFETs are turned on, the active driving circuit drives the main power circuit to rotate; current sharing when a plurality of SiC MOSFETs are connected in parallel is realized through an in-phase amplification circuit used for detecting and amplifying an induced voltage, a differential amplification circuit used for detecting and comparing an induced voltage value, and a proportional current source circuit is controlled to extract a SiC MOSFET gate drive current. By adopting the method, the unbalanced current can be suppressed, the balance of the current flowing through each branch of the parallel SiC MOSFETs is ensured, the SiC MOSFET device in the high-voltage pulse power supply is effectively protected, and the working reliability of the circuit is improved.

The invention discloses an electric leakage detection method based on wavelet transform harmonic suppression, and the method comprises the steps: synchronously collecting a current signal through a dual-channel differential sampling circuit, and obtaining two paths of differential voltages; after common-mode interference is eliminated through differential amplification and impedance matching, low-pass filtering and digital conversion are carried out; extracting signal multi-scale energy characteristics by using wavelet decomposition, and setting a threshold value to separate leakage low-frequency components from high-frequency noise; a pure electric leakage signal is obtained through inverse wavelet reconstruction, and a high-speed switching circuit compares a preset threshold value to trigger a protection action. According to the scheme, differential sampling, impedance matching and wavelet analysis technologies are combined, the signal-to-noise ratio and the detection precision are effectively improved, the problems that in the prior art, electric leakage signals are prone to interference and slow in response speed are solved, and the reliability and the real-time performance of electric leakage protection are remarkably improved.

The invention relates to the technical field of motor testing, in particular to an electromechanical equipment fault diagnosis system and method based on machine learning, and the system comprises a high-frequency signal injection module which injects a high-frequency signal in the range of 10 kHz to 50 kHz into a motor through a power supply line, analyzes the electromagnetic response of the signal, and obtains electromagnetic parameter monitoring data; and based on the electromagnetic parameter monitoring data, statistical characteristics are extracted and pattern recognition is carried out, and an early fault characteristic signal is generated. According to the invention, through high-frequency signal injection and differential signal amplification, early recognition and accurate positioning of motor faults are realized. By injecting high-frequency signals, changes in electromagnetic parameters can be captured, which often occur prior to physical fault performance. Differential amplification further enhances the ability to extract useful signals from these small changes, which can be identified and responded before the fault develops to a more serious stage.

The invention relates to the technical field of electronic circuits, in particular to a common-mode rejection circuit which is applied to a differential amplification circuit and comprises a common-mode disturbance rejection circuit and an output common-mode detection circuit. A first input end and a second input end of the output common-mode detection circuit are respectively connected with a first common-mode output end and a second common-mode output end of the differential amplification circuit; the output end of the output common-mode detection circuit is connected with the input end of the common-mode disturbance suppression circuit; a first output end and a second output end of the common-mode disturbance suppression circuit are respectively connected with a first common-mode input end and a second common-mode input end of the differential amplification circuit; the output common-mode detection circuit generates control information according to respective voltages of the first common-mode output end and the second common-mode output end; and the common-mode disturbance suppression circuit adjusts the common-mode voltage of the differential amplification circuit based on the control information, so that common-mode currents flowing in and out of the same common-mode input end are the same, or the common-mode voltage is one half of the voltage of the power supply. Therefore, the voltage disturbance of the common-mode input end is effectively inhibited.

The invention provides an anti-interference pressure sensor signal conditioning circuit based on a differential amplification structure, and the circuit comprises a differential input module which is used for receiving a differential signal outputted by a pressure sensor, and carrying out the amplification and filtering of the outputted differential signal, and obtaining a first differential signal; the common-mode suppression module is electrically connected with the differential input module and is used for suppressing a common-mode signal in the first differential signal to obtain a second differential signal; the programmable gain amplification module is electrically connected with the common-mode suppression module and is used for performing programmable gain amplification on the second differential signal to obtain a third differential signal; the low-pass filtering module is electrically connected with the programmable gain amplification module and is used for filtering high-frequency noise in the third differential signal to obtain a fourth differential signal; and the output buffer module is electrically connected with the low-pass filtering module and is used for converting the fourth differential signal into a single-ended signal and outputting the single-ended signal. According to the invention, external electromagnetic interference and common-mode noise can be effectively suppressed, and the stability and accuracy of signal transmission are improved.

The invention provides a laboratory digital management method and system, electronic equipment and a storage medium, and relates to the technical field of laboratory automation and spectral analysis. The method comprises the following steps: acquiring a multi-wavelength spectral image sequence in an experimental reaction container in a non-contact manner, associating the multi-wavelength spectral image sequence with a final performance index, and performing differential enhancement to generate a spectral change feature map; performing differential amplification on the spectral electric signal to suppress noise and enhance an effective signal, dividing a region of interest according to a container structure, calculating average spectral intensity, and generating a spectral response curve; the method comprises the following steps: extracting first-order and second-order derivative curves, identifying an intensity change inflection point and a slope abrupt change interval, screening out a key optical change mode in combination with a final performance index, finally establishing a mapping relation between the key optical change mode and the performance index, and constructing a digital model for monitoring a reaction state and predicting final performance. The reaction process can be monitored and the experiment result can be predicted through the spectrum change characteristics, so that the intelligence and accuracy of laboratory management are improved.

The invention provides a temperature drift compensation method, device and equipment for a Hall current sensor, and relates to the technical field of Hall sensors. The method is applied to a temperature excursion compensation system, the temperature excursion compensation system comprises a temperature sensor, a microprocessor, a temperature excursion prediction model, a compensation signal generation module and a differential amplification circuit, and the temperature excursion compensation method comprises the following steps: acquiring environment temperature data of a Hall current sensor by using the temperature sensor; the microprocessor calculates a temperature drift error parameter corresponding to the current environment temperature data based on the environment temperature data and a temperature drift prediction model; the compensation signal generation module generates a corresponding compensation signal based on the temperature drift error parameter, and the compensation signal and the temperature drift error represented by the temperature drift error parameter are equal in size and opposite in direction; and superposing the compensation signal and an original sampling signal of the Hall current sensor through a differential amplification circuit to obtain a final current signal. The measurement accuracy of the Hall current sensor can be improved.

The invention discloses a single-power-supply ultra-wideband temperature compensation low-noise amplifier circuit, and belongs to the technical field of radio frequency microwaves. The circuit is mainly composed of a pre-stage low-noise amplifier module, an inter-stage temperature compensation equalization module and a post-stage driving amplifier module. The temperature compensation equalizer module generates differential voltage related to temperature through a three-stage gallium arsenide diode temperature sensing unit, outputs a control signal through an enhanced FET differential amplification circuit, drives a voltage-controlled attenuation equalizer to dynamically adjust the attenuation amount of a radio frequency signal, and achieves gain stability in a frequency band. Through the collaborative design of a blocking capacitor and a divider resistor, the grid bias of an FET switch is strictly limited in a transconductance linear adjustment interval, and the interval covers 80% of the effective range of the threshold voltage of a gallium arsenide FET tube. The circuit is powered by a single power supply + 5V, stable work of each module is ensured through active bias and a power supply filter network, and the circuit is suitable for extreme temperature environments such as high-frequency communication and radar.

The utility model discloses a wide-temperature-range high-precision detection circuit for measuring the temperature of a heating device based on an NTC (Negative Temperature Coefficient), and belongs to the technical field of dehumidifiers. A measurement temperature range of the detection circuit is divided into two measurement sub-temperature ranges which correspond to two gears of the detection circuit; the circuit comprises a bridge unit, a low-pass filtering unit, a buffer amplification unit and a differential amplification unit which are electrically connected in sequence, the four resistors of the bridge unit are respectively a first bridge circuit, a second bridge circuit, a third bridge circuit and a fourth bridge circuit; according to the fourth bridge circuit, an NTC unit is connected with a fourth resistor R4 in series and then connected with a fifth resistor R5 in parallel through a first analog switch U1. The fourth bridge circuit is controlled by the first analog switch U1 to switch two resistance modes, and the two resistance modes correspond to the two measurement sub-temperature ranges respectively.

Low noise amplifiers (LNAs) are disclosed herein. In certain embodiments, an LNA includes an input balun configured to convert a single-ended radio frequency (RF) receive signal to a differential RF receive signal, an amplifier chain configured to amplify the differential RF receive signal to generate a differential amplified RF receive signal, and an output balun configured to convert the differential amplified RF receive signal into a single-ended amplified RF receive signal. The LNA's amplifier chain is operable in multiple gain modes, and includes a first differential amplification stage, a second differential amplification stage, and a third differential amplification stage.

The invention discloses an arc fault detection method, system and device. The method comprises the following steps: inputting a reference analog current time-domain signal and an actual analog current time-domain signal which are matched with an actual analog current time-domain signal of a DC bus to be measured into a time-domain waveform differential amplification module to obtain time-domain signal difference data; inputting actual simulation current frequency domain data corresponding to the actual simulation current time domain signal and reference simulation current frequency domain data into a frequency domain waveform differential amplification module to obtain frequency domain signal difference value data; and inputting the time domain signal difference value data and the frequency domain signal difference value data into a pre-constructed target arc fault detection model for feature recognition to obtain an arc fault detection result. According to the method, the accuracy and rapidity of arcing fault judgment of the whole system are effectively improved, and the false alarm rate during non-arcing is effectively reduced, so that a more reliable guarantee is provided for safe and stable operation of an electrical system.

The invention relates to the technical field of semiconductor lasers, in particular to an integrated double-closed-loop control surface emitting laser detection module and a control method.The detection module comprises an optical feedback unit which comprises photoelectric detectors integrated behind a gas chamber and beside a laser respectively and is used for detecting transmission light intensity and reflection light intensity; carrying out differential amplification according to the projection light intensity and the reflection light intensity so as to generate a wavelength locking feedback signal; the double temperature control unit comprises a temperature detection module and a heating module which are arranged at the air chamber and the laser, and is used for monitoring temperature signals at the air chamber and the laser and controlling the temperature of the laser and the air chamber through the heating module; and the cooperative control unit is connected with the optical feedback unit and the double temperature control unit and is used for adjusting the current and the temperature of the laser according to the wavelength locking feedback signal. According to the scheme of the invention, accurate wavelength-absorption peak matching is still maintained in a high-temperature environment, and the wavelength locking precision and the spectrum detection signal-to-noise ratio are effectively improved.

The invention discloses a battery total voltage acquisition precision calibration method for a BMS (Battery Management System). Comprising the following steps: calibrating a hardware circuit, and calibrating software. The hardware circuit is composed of a resistance voltage divider, a relay A, a differential amplification circuit, a relay B, an ADC chip, a voltage reference and an MCU, the resistance voltage divider is connected with the relay A, the relay A is connected with the differential amplification circuit, the differential amplification circuit is connected with the relay B, the relay B is connected with the ADC chip, the voltage reference and the MCU, the ADC chip is connected with the MCU, and the MCU is connected with the relay A. Vos and a voltage reference error are calculated through switching of the front-stage relay set and the rear-stage relay set, the voltage acquisition precision can be rapidly and efficiently calibrated, and then the voltage acquisition precision is further improved through software calibration.