381 results about "Common-mode interference" patented technology

The invention discloses an online multi-channel rapid gas chromatographic analysis system and method, particularly relates to the technical field of gas chromatographic analysis, and is used for solving the problems of baseline noise rise and trace component detection precision reduction caused by physical coupling and signal interference when multiple detectors work in parallel in the prior art. Interference signal features of adjacent detection channels are extracted, a chaotic or linear compensation signal is dynamically generated in combination with harmonic primary and secondary sorting and recursive quantization factor analysis, and common-mode interference of a target channel is suppressed. Electromagnetic isolation parameters of a shielding structure are adjusted in real time based on the baseline signal after noise suppression, and accurate matching of impedance and interference spectrum is achieved; further separating time domain overlapped signals and analyzing asymmetric distortion characteristics, and eliminating system errors through normalization calibration; dynamic interference suppression, electromagnetic shielding optimization and signal distortion traceability are combined, the anti-interference capability and analysis precision of multi-channel detection are remarkably improved, and the method is suitable for high-throughput rapid detection scenes of complex samples.

The invention discloses a high-voltage circuit for an electric flame stove. The high-voltage circuit comprises a PFC circuit, a high-frequency conversion circuit, a boosting transformer, an energy coupling circuit and a voltage doubling circuit which are electrically connected in sequence. According to the EMI filter circuit, common-mode interference and differential-mode interference are filtered out, and pure alternating current input is provided for a back-end PFC circuit; two chips are adopted in the PFC circuit, so that the PFC circuit 300 finally realizes the consistency of the current waveform and the voltage phase; in the other embodiment of the invention, double chips are adopted, so that'fault linkage protection 'is realized; stable discharging of multiple groups of positive and negative electrodes is achieved through multiple groups of single energy coupling capacitors and independent voltage doubling rectifier bridges which are connected in parallel.

The invention provides a method for testing the stability of an electronic product, and the method comprises the steps: obtaining the propagation characteristic data of a transient current in a grounding network, building a multi-point grounding network model in combination with the potential distribution data of each node, inputting the potential of the nodes and the transient current data, and predicting the fluctuation trend of the ground potential through the multi-point grounding network model; according to the predicted ground potential fluctuation trend, extracting a coupling path of an interference signal in the grounding network when common-mode interference exists, and determining a main node and a propagation direction of interference signal propagation to obtain a sensitive circuit; calculating node potential distribution data of the grounding network after node layout, judging whether the potential difference between key nodes is within a preset range or not, and if the potential difference exceeds the preset range, refining network division, increasing equipotential connection or locally reducing grounding resistance; and determining a matching design scheme of the grounding network and the sensitive circuit according to the anti-interference capability, building a test platform, and testing stability data of the grounding system in different electromagnetic environments.

The invention relates to the technical field of optical fiber sensing, and discloses an optical fiber sensing signal adaptive demodulation analysis method for inhibiting common-mode interference, which comprises the following steps of: synchronously acquiring an original signal of a main sensing optical fiber channel and a common-mode interference signal of a reference optical fiber channel, and performing time-frequency conjoint analysis on the signal of the reference optical fiber channel to obtain a common-mode interference signal; s2, extracting an interference spectrum component containing temperature drift and light source fluctuation characteristics, constructing a hybrid adaptive filter bank which comprises a recursive least square (RLS) filter and a variable step size least mean square (LMS) filter which are connected in parallel, and dynamically adjusting a forgetting factor of the RLS filter and a step size factor of the LMS filter based on the interference spectrum component extracted in the step S2, according to the optical fiber sensing signal adaptive demodulation analysis method for suppressing common-mode interference, a parameter adjustment strategy is continuously optimized, a pure vibration signal with an output signal-to-noise ratio is improved, and the effect of accurately suppressing common-mode interference in real time is achieved.

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 provides an automobile wire harness short circuit fault detection method, system and device and a medium, and the method comprises the steps: extracting the transient characteristic quantity of a current signal of each monitoring node, and obtaining the amplitude attenuation characteristics of the current signal of each monitoring node in a wire harness propagation process based on the mutual information intensity inversion of the transient characteristic quantity between adjacent monitoring nodes; further identifying an abnormal wire harness path which is obviously influenced by common-mode interference based on the fluctuation difference degree of the amplitude of the common-mode current between adjacent monitoring nodes in spatial distribution, and constructing a common-mode interference topological graph which represents the abnormal state of the wire harness in combination with the response intensity of the common-mode current; and performing fuzzy reasoning on the short-circuit fault probability of each monitoring node according to the amplitude attenuation characteristics corresponding to each monitoring node and the common-mode interference topological map to obtain the fault membership degree of each monitoring node, and performing short-circuit fault correlation positioning on the target automobile wire harness through all the fault membership degrees. By adopting the scheme of the invention, the associated positioning of the short-circuit fault of the automobile wire harness under the common-mode interference condition can be realized.

The embodiment of the invention provides a power transmission system and a power generation system. The power transmission system comprises: a power conversion circuit for performing power conversion on an input electric signal; the filter circuit comprises a first filter circuit and a second filter circuit, and the first filter circuit is coupled between the input end of the power transmission system and the input end of the power conversion circuit; the second filter circuit is coupled between the output end of the power conversion circuit and the output end of the power transmission system; one end of the bridging capacitor bank is coupled with the input end of the power transmission system, and the other end of the bridging capacitor bank is coupled with the output end of the power transmission system, so that a loop is formed, and interference signals in the electric signals output by the output end of the power conversion circuit can flow back to the input end of the power conversion circuit. According to the embodiment of the invention, the interference signal can flow back, the common-mode interference current at the input end and / or the output end is reduced, a safety Y capacitor does not need to be adopted, the size of the filter inductor can be reduced, and the cost is reduced.

The invention discloses a differential closed-loop negative feedback amplification circuit based on JFET geminate transistors, a low-noise amplifier is used for measuring weak voltage signals, discrete JFET field-effect transistors are used for forming an input stage of the low-noise amplifier, noise interference is reduced, meanwhile, extremely high input impedance can be provided by using the characteristic that the grid current of the JFET field-effect transistors is basically zero, and the differential closed-loop negative feedback amplification circuit based on the JFET geminate transistors is obtained. Mirror current is provided for a pair of JFET field effect transistors in the low-noise amplifier module through a current mirror of the low-noise amplifier, a closed-loop feedback structure of the low-noise amplifier can save one path of input for the JFET field effect transistors, so that the amplifying circuit can realize dual-channel input, and a dual-channel input structure can enable an accessed signal to be a differential signal, so that common-mode interference is effectively inhibited, and the reliability of the amplifying circuit is improved. Overall closed-loop negative feedback can achieve high gain stability, reduce nonlinear distortion, increase input impedance, reduce output impedance and improve the performance of the amplifier, and solves the problem of precise amplification and measurement of weak voltage signals in the aviation electromagnetic field.

The invention provides a silicon carbide MOS drive control chip overcurrent protection method and device, and the method comprises the steps: setting a forward sampling channel and a reverse sampling channel at a source sampling resistor, setting different sampling time windows for different sampling channels, carrying out the peak shifting setting of the time windows of the double sampling channels, and carrying out the peak shifting setting of the time windows of the double sampling channels, thereby achieving the overcurrent protection of a silicon carbide MOS drive control chip. The time period with the strongest common-mode interference can be avoided; meanwhile, the switching speed of the silicon carbide MOS device is mapped into a theoretical common-mode interference waveform, and the waveform and a bidirectional sampling signal are synthesized, so that a common-mode interference component in the sampling signal can be accurately separated, and the synthesized current signal is more accurate; on the basis, current signals are compensated by combining on-resistance change caused by junction temperature change, and overcurrent protection is carried out by adopting a graded protection strategy. According to the method, the influence of common-mode interference on current sampling is effectively overcome through peak shifting design on sampling channel time and common-mode interference separation based on switching speed.

The invention discloses an active pen and touch screen interaction system resistant to common-mode interference and a signal demodulation method. The system comprises a signal receiving terminal and a signal transmitting terminal. The signal transmitting terminal modulates data to be transmitted by adopting a differential binary phase shift keying modulation method, and transmits a generated modulation signal to the signal receiving terminal; the analog front-end receiving module is coupled with the signal transmitting terminal, receives the modulation signal and outputs a digital square wave signal after fidelity extraction processing; and the digital demodulation processing module performs differential coherent digital demodulation on the digital square wave signal based on the prior characteristics of the modulation signal, inhibits residual noise and recovers data to be sent. The analog front end focuses strong common-mode noise suppression and analog filtering, the digital demodulation algorithm performs secondary digital purification by using signal time sequence characteristics, and the two constructs an efficient anti-interference pipeline. Meanwhile, the regular square wave signals can be directly processed through differential coherent demodulation, and the requirements for performance and power consumption of a rear-end processor are lowered.

The invention discloses an anti-interference system for a slip ring communication technology, and belongs to the technical field of communication. Aiming at the problems of electromagnetic interference, mechanical vibration and unstable contact of monocrystalline silicon furnace equipment, a collaborative solution is provided. The system comprises a conductive slip ring assembly, a dynamic shielding module, an asymmetric differential transmission module, an intelligent filtering module, an environment sensing module and a contact impedance compensation module, and real-time cooperative control is realized through a bus controller. The dynamic shielding module adopts a liquid metal micro-channel layer and a piezoelectric driving layer, the shielding density is dynamically reconstructed according to the electromagnetic interference frequency band and the vibration intensity, and broadband noise is suppressed; the asymmetric differential transmission eliminates common-mode interference through dynamic phase compensation; the intelligent filtering module adaptively adjusts parameters of a band elimination filter based on a deep learning model, and accurately suppresses time-varying interference; the carbon nanotube composite electric brush stabilizes contact impedance through a pressure feedback mechanism. The system is obviously superior to a traditional static shielding and fixed filtering scheme, and reliable communication requirements are guaranteed.

The invention provides a novel broadband simulation multiple correlation type microwave radiometer, and relates to the technical field of passive remote sensing detection. The system comprises a double-path correlation radio frequency front-end unit, an intermediate-frequency filtering and amplifying unit and an analog multiple correlation unit, wherein the analog multiple correlation unit comprises two analog multiple correlation channels, each analog multiple correlation channel comprises a broadband multiplication unit and an active differential filtering unit, and the broadband multiplication units are used for carrying out differential conversion on input same signals and orthogonal signals and carrying out correlation operation; and performing active differential filtering processing on the signal after the correlation operation through an active differential filtering unit, and outputting two paths of orthogonal differential parameters. The analog multiple correlation unit designed by the invention adopts a full-link differential design, including differential passive / active filtering, amplification and transmission, the design can provide amplitude twice as large as that of a single-ended signal and better linearity under the same power supply voltage, and meanwhile, the problems of direct-current drift and common-mode interference suppression are solved.

The invention relates to a current-to-voltage acquisition circuit for suppressing common-mode interference. The current-to-voltage acquisition circuit comprises a current amplification module, a current transformer, a high-pass filter, an interference acquisition module, an interference analysis module and a suppression execution module, by means of the design, the common-mode interference suppression effect is better than that of a traditional sampling circuit, errors caused by sampling signal deviation generated by interference are avoided to the maximum degree, the common-mode interference suppression circuit is particularly suitable for interference scenes or occasions where interference sources change, the changed interference sources can be calculated in a sampling statistics mode, and the interference source suppression effect is improved. Therefore, the suppression ratio of common-mode suppression is adjusted, and the environment condition is dynamically tracked to obtain an accurate sampling effect.

The invention relates to the technical field of power management, in particular to a buck-boost bidirectional DCDC converter control method and system and a storage medium, and the method comprises the steps: obtaining a DC bus voltage and a battery voltage of a converter; the switching frequency, the dead time and the bus voltage of the converter are obtained, and hysteresis parameters are calculated based on the switching frequency, the dead time and the bus voltage; the correlation between the direct current bus voltage and the battery voltage is obtained based on the hysteresis parameter, the working modes needing to be operated of the converter are judged based on the correlation between the direct current bus voltage and the battery voltage, and the working modes comprise the BUCK mode, the BOOST mode and the upper tube direct connection mode; and adjusting the PWM waveform of the driving switch tube so as to control the operation of a corresponding working mode. The defects that a traditional control mode is large in switching loss, high in common-mode noise and low in specific working condition efficiency are effectively overcome, the conversion efficiency of the converter is remarkably improved, common-mode interference is reduced, and the electric energy conversion stability and reliability are enhanced.

The invention discloses a broadband electromagnetic radiation interference characteristic modeling method for a shielding cable network. The method comprises the following steps: 1) obtaining a scattering parameter matrix of a shielding connector and a transmission parameter matrix of a bent shielding cable; 2) constructing an equivalent N port model of the shielding connector by using the scattering parameter matrix, and deducing a transmission parameter matrix of the shielding connector; 3) establishing a multi-conductor transmission line equation reflecting the distribution of interference current on the shielding cable by using the shielding cable transfer impedance; 4) cascading the transmission parameter matrixes of all the bent shielding cables and the shielding connectors to obtain an overall transmission parameter matrix of the shielding cable network; and 5) solving the multi-conductor transmission line equation in combination with the boundary constraint condition to obtain the common-mode interference current of the shielding layer of the shielding cable, and calculating the electric field radiation of the shielding cable network through the dipole array theory. The method is suitable for uniform and non-uniform shielding cables and shielding cable networks of single-core and multi-core wire harness shielding wire types, and has good universality.

The invention provides a silicon micro gyroscope, which belongs to the technical field of inertial angular velocity detection, and comprises a substrate, a mass unit, a driving unit and a detection unit, the mass unit comprises two mass modules, the two mass modules are connected through a first elastic coupling beam, and the mass modules are connected to the substrate through the first elastic coupling beam; the driving unit comprises a plurality of driving modules arranged on the periphery of the mass unit in a surrounding mode, the driving modules are fixed to the base plate through the second elastic modules, the driving modules are used for receiving electric signals input from the outside, the driving modules move along the X axis and drive the mass module to do torsion simple harmonic motion along the Y axis, and when the inertia angular rate around the X axis is input from the outside, the mass module does torsion simple harmonic motion along the Y axis. The mass module rotates by taking the Y axis as a rotating shaft; the detection unit is arranged between the quality unit and the substrate. The silicon micro-gyroscope provided by the invention aims to solve the problem that the silicon micro-gyroscope in the prior art is poor in common-mode interference signal suppression capability and low in detection sensitivity and signal-to-noise ratio, so that the overall detection precision is low.

The invention relates to the field of power electronic devices, in particular to an all-fiber isolation SiC MOSFET grid driver suitable for ultrahigh voltage and application, the all-fiber isolation SiC MOSFET grid driver comprises a transmitting side, a fiber group and a receiving side which are connected in sequence, the transmitting side comprises a constant-current laser driver, a semiconductor fiber coupling laser, a fiber coupler of an FC connector, a high-speed light emitter driver and a light emitter, and the receiving side comprises a high-speed light emitter driver and a high-speed light emitter. The optical fiber group comprises a quartz power optical fiber and a plastic signal optical fiber of an FC (Fiber Channel) joint, and the receiving side comprises a beam expander, a laser battery, a 5V boost IC (Integrated Circuit), a 25V boost IC, an optical receiver, a non-isolated driving IC and a push-pull current expanding circuit. And common-mode interference caused by a coupling capacitor is eliminated. Meanwhile, the efficiency of a device is reasonably calculated, and a high-efficiency boost IC is matched, so that the driving power of 0.8 W is realized, and a 6.5 kV 25A high-voltage SiC MOSFET module can be driven to work at the switching frequency of more than 100kHz.

The invention discloses a CAN bus activity detection and wake-up circuit and method, and belongs to the technical field of CAN bus communication, the CAN bus activity detection and wake-up circuit comprises a CAN bus interface circuit, a signal detection and processing circuit and a controller, the input end of the CAN bus interface circuit is connected with a CAN bus; the signal detecting and processing circuit comprises a voltage comparator, the non-inverting input end and the inverting input end of the voltage comparator respectively receive a CANH signal and a CANL signal which are electrically isolated by the CAN bus interface circuit, and the output end of the voltage comparator is connected to a wake-up pin of the controller; the controller is used for monitoring the level state of the wake-up pin, and when the level of the wake-up pin is in an effective state, the electronic equipment is controlled to be switched from the sleep mode to the normal working mode. By introducing an electrical isolation and voltage difference detection mechanism, the problem of false wake-up caused by common-mode interference or bus noise in the prior art is solved, and reliable wake-up under low power consumption is realized.

The invention provides an intelligent current sensor and method, and the method comprises the steps: carrying out the state offset estimation of the current monitored by sensor nodes according to the time-space relation between sensor nodes, and obtaining the state offset of the current of the sensor nodes; extracting the electromagnetic interference quantity of each sensor node from the electromagnetic interference information, and determining an electromagnetic coupling coefficient of common-mode interference between the sensor node and other sensor nodes according to the array relationship between the sensor nodes and all the electromagnetic interference quantities; determining the interference compensation amount of each sensor node current through the state offset of the sensor node current and all the electromagnetic coupling coefficients; and when the state offset of the current of the sensor node is greater than a preset offset threshold value, adaptive compensation is carried out on the monitored current according to the interference compensation amount to obtain a compensation current. By adopting the scheme of the application, adaptive compensation of the intelligent current sensor to the monitored current data can be realized, so that the measurement reliability of the multi-phase power system is improved.

The invention relates to the technical field of sensors, and discloses a continuous glucose sensing device based on a microneedle array and a preparation method, the device comprises a base and a metal microneedle array, the base is a printed circuit board, conductive contacts are attached to the back surface of the base, and a metal through hole array is arranged on the base; the metal microneedle array is fixed in the metal through hole array from the front surface of the base; the adjacent metal microneedles are electrically connected, and the metal microneedles and the conductive contacts are electrically connected. The metal microneedle array is divided into a glucose sensing area and a differential sensing area, metal microneedles in the glucose sensing area and the differential sensing area are modified to comprise counter electrodes, working electrodes and reference electrodes, the working electrodes of the glucose sensing area are modified with glucose oxidase layers, and the reference electrodes of the glucose sensing area are modified with reference electrodes. And no glucose oxidase layer is arranged on the working electrode in the differential sensing area. By introducing the differential sensing electrode, common-mode interference signals caused by other electrochemical active substances can be effectively removed, and an accurate detection result is obtained.

The invention discloses a diagnosis and measurement system for an electromagnetic compatibility experiment and a matched rectification system. The diagnosis and measurement system comprises a broadband LISN, a difference and common mode interference separation module, a radiation emission interference positioning module, ultra-wideband current calipers, a system power supply line rectification assembly and a system internal interconnection cable rectification assembly. The system provides stable impedance through a broadband LISN, samples high-frequency and low-frequency interference signals by using a difference and common mode interference separation module and a current caliper, and separates a difference mode component from a common mode component. And the radiated emission interference positioning module detects equipment radiation leakage points and generates a shielding effectiveness report. The rectification assembly quickly solves the electromagnetic compatibility problem of the equipment, and ensures that the test standard is met. The system realizes efficient and accurate electromagnetic interference detection and rectification.

The invention provides a common-mode interference suppression method and device for current sampling of a permanent magnet synchronous motor, and relates to the technical field of power electronic electromagnetic interference, and the method comprises the steps: collecting the three-phase current of the permanent magnet synchronous motor based on a preset sampling frequency, and calculating the common-mode current of the three-phase current; determining a corresponding common-mode current amplitude based on the common-mode current of the three-phase current, and comparing the common-mode current amplitude with a preset threshold to obtain a comparison result; and under the condition that the comparison result indicates that the amplitude of the common-mode current accords with the preset threshold value, calculating and adjusting direct-axis current and quadrature-axis current at the next moment based on a prediction compensation algorithm so as to realize suppression of common-mode interference. Through the method provided by the invention, the suppression of the common-mode interference is realized, additional hardware filtering is not needed, the economic cost is low, and meanwhile, the reliability of system operation 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 discloses a signal high-frequency interference resisting device and method for electrical resistance tomography. A high-frequency filtering unit in the device comprises a magnetic ring, a coaxial shielding line, a first resistor and a second resistor; the coaxial shielding lines are connected between the corresponding detection electrodes and the signal sampling ends, and the first resistors are connected between the first ends of the signal lines in the corresponding coaxial shielding lines and the first ends of the signal lines in the next coaxial shielding lines. The second resistor is connected between the second end of the signal line in the corresponding coaxial shielding line and the second end of the signal line in the next coaxial shielding line; the first end of the signal line in the coaxial shielding line is also connected with the first end of the shielding layer in the next coaxial shielding line; the magnetic rings sleeve the outer layers of all the coaxial shielding wires and are tightly attached to the outer layers of the coaxial shielding wires, filtering on a transmission line is achieved, the twisted-pair coaxial shielding wire magnetic rings are combined to serve as transmission wire harnesses, a hardware coupling filter circuit between the wire harnesses is constructed, the suppression effect of common-mode interference is improved, sampling signals are more real, and imaging is clearer.

The invention discloses a linear motor position detection method based on a space Hall element, belongs to the technical field of linear motors, and realizes high-precision position detection through cooperative work of a reference Hall element and a plurality of compensation Hall elements. The compensation Hall elements are distributed on the positive side and the negative side of the reference element in the axial direction in a non-equidistant gradient mode to form differential signal pairs to eliminate common-mode interference, and the sensitivity coefficient is dynamically adjusted by combining the axial distance An and the radial distance Ln. And the anomaly detection mechanism monitors the deviation value in real time, switches the redundant component group when the deviation value exceeds a threshold value and generates a fault diagnosis signal. According to the method, through a multi-dimensional signal fusion and dynamic compensation strategy, the detection precision, the anti-interference capability and the system reliability under complex working conditions are remarkably improved.

The invention belongs to the technical field of visible light wireless laser communication, and particularly relates to a dual-polarization dual-aperture multi-wavelength visible light wireless laser communication system. The system comprises a digital signal processing module, two groups of five-wavelength laser transmitting modules and an in-phase or anti-phase transmitting module based on polarization multiplexing at a transmitting end, and a dual-aperture receiving module, a maximum ratio merging or differential processing module and a receiving end digital signal processing module at a receiving end, according to the invention, complementary dual-polarization in-phase transmission of damages in horizontal and vertical polarization directions and dual-polarization differential transmission of common-mode interference suppression can be realized. For dual-polarization in-phase transmission, the two groups of lasers modulate the same signals, and a receiving end adopts a maximum-ratio merging algorithm to perform merging; for dual-polarization differential transmission, two groups of lasers modulate inverted signals, and receiving of two apertures of a receiving end is differentiated. According to the invention, the reliability and robustness of communication can be greatly improved, and higher-rate and larger-capacity communication can be realized.

The invention provides an electrode impedance test system for physical therapy. The electrode impedance test system comprises a microcontroller, a D / A conversion circuit, a power amplification circuit, a voltage detection circuit, a current detection circuit and a boosting transformer circuit. The microcontroller generates a square wave signal, the square wave signal is converted into a sinusoidal signal through the D / A conversion circuit, and the sinusoidal signal is amplified through the power amplification circuit. The boosting transformer transmits the amplified sinusoidal signal to the electrode slice, and the secondary side of the boosting transformer is connected with the voltage and current sampling circuit and is used for collecting a differential signal. According to the system, the electrode impedance of the electrode plates is detected through voltage and current sampling of the pair of electrode plates, common-mode interference and signal distortion are eliminated through the differential signal amplification circuit and the full-wave precision rectification circuit, and high-precision acquisition and detection of signals are ensured. The detected and rectified signals are converted into digital signals through the A / D conversion circuit, and the digital signals are input into the signal input end of the microcontroller.

The invention relates to the technical field of temperature sensing, and provides a temperature sensor detection circuit and semiconductor temperature control equipment, and the circuit comprises a constant current source module which is used for providing constant current; the thermosensitive module is connected with the constant current source module, and the thermosensitive module is used for obtaining the constant current to form temperature detection voltage corresponding to the temperature; the input end of the multi-stage differential module is connected with the thermosensitive module, the output end of the multi-stage differential module is used for being connected with the analog-to-digital conversion module, and the multi-stage differential module is used for carrying out at least two-stage differential processing on the temperature detection voltage to form a detection output signal. The thermosensitive module outputs temperature detection voltage corresponding to the temperature under the action of constant current, the multi-stage differential module obtains the temperature detection voltage for differential processing, the influence of common-mode interference is reduced, the multi-stage differential module carries out at least two-stage differential processing, the common-mode interference is further removed, and an output detection output signal has the advantage of high precision. And the requirement of semiconductor production on temperature detection is met.

The invention discloses an output current sampling evaluation system for a double-shaft low-voltage motor driver. The output current sampling evaluation system comprises a single-resistance signal acquisition module, a common-mode interference suppression module, a double-shaft current separation module, a current parameter extraction module, a sampling precision evaluation module and an evaluation result integration module. The system collects bus current signals through a single resistor, interference is filtered out through a common-mode interference suppression module based on an equivalent common-mode circuit model, then double-axis current signals are separated out through a double-axis current separation module according to a single-resistor bus current sampling model, after characteristic parameters are extracted, precision data are generated through sampling precision evaluation, and the precision data are analyzed through an analysis module. And finally integrating into a comprehensive evaluation report. According to the system, the problems of insufficient biaxial coupling processing and lack of common-mode interference evaluation systematicness in traditional evaluation are solved, and the accuracy and comprehensiveness of biaxial current sampling evaluation are improved.

The invention discloses a driving power supply fault switching method and system, particularly relates to the technical field of power system relay protection, and is used for solving the problem that an existing relay power supply switching system causes misoperation due to common-mode interference caused by ground fault transient potential gradient. An earth screen potential gradient is collected in real time, a control cable orthogonal electric field component is measured synchronously, an electric field fiber bundle structure is reconstructed based on topology invariant distribution of a cable surface topology sequence substance, and a common-mode interference coupling coefficient is generated according to a space vector relation between an earth screen gradient direction and a reconstructed electric field; the coupling coefficient is converted into electrostrictive strain through the inverse piezoelectric effect, then a dynamic compensation voltage instruction is generated, finally, the compensation instruction is superposed to a power supply control loop to drive a standby power supply to be switched, the coupling influence of earth screen transient interference on a relay is eliminated from the physical mechanism level, the problem of misoperation is fundamentally solved, and the reliability of the relay is improved. And the reliability of power supply switching of the ultrahigh-voltage power transmission and transformation system is