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813 results about "Constant current source" patented technology

Abnormality monitoring system applied to plasma etching machine

The embodiment of the invention discloses an abnormity monitoring system applied to a plasma etching machine. The abnormity monitoring system comprises constant current source equipment, a coil, a coil detection circuit and a controller, and the constant current source equipment is configured to output driving current according to preset etching process parameters; the coil is configured to generate a magnetic field in the etching cavity in response to the input of the driving current to guide the plasma to move towards the direction of the substrate so as to etch the substrate; the coil detection circuit is configured to detect coil state data of the coil; the controller is configured to generate device service information based on the coil state data. According to the embodiment of the invention, the working state of the coil is monitored through the coil state data, and the actual condition of the coil is reflected through the equipment maintenance information, so that a user can quickly know whether the coil is in an abnormal state, the user is helped to quickly position the maintenance direction, the user is prevented from detaching and maintaining the coil from the etching cavity, and the user experience is improved. And various resource investments wasted due to the fact that the coil is abnormal do not exist.
Owner:SHENZHEN HUAXIN SEMICON EQUIP TECH CO LTD

High-precision time interference non-invasive deep brain electrical stimulation method, device and system

The invention relates to the technical field of medical instruments, in particular to a high-precision time interference non-invasive brain deep electrical stimulation method, equipment and system, and solves the problems that two stimulation electrodes are used for each pair of current in traditional time interference-based non-invasive brain deep electrical stimulation, so that the current distribution is relatively dispersed, and the stimulation focusing performance is relatively poor. According to the method, high-precision 4 * 1 electrode configuration is used, two electrodes for applying a stimulation current are changed into a 4 * 1 electrode form, the flowing path of the current is effectively limited, the current is more focused, and the focusing performance of the interference current is further improved. According to the device, high-precision current control is realized through the anti-phase output circuit, the 4 * 1 voltage division circuit, the constant current source module and the impedance detection module; the system supports forward and reverse electrode position optimization, a personalized real finite element head model simulation system based on MRI data is used for guiding practical application, the focusing performance of each pair of current in a target brain region is improved, and therefore the overall stimulation precision in the target brain region is improved.
Owner:XIAN NEURODOME MEDICAL TECHNOLOGY CO LTD

Platinum resistor high-precision temperature measuring device capable of automatically identifying wiring mode and temperature measuring method

The invention discloses a platinum resistor high-precision temperature measuring device capable of automatically identifying a wiring mode. The platinum resistor high-precision temperature measuring device comprises a power supply module, a signal detection module, an isolation module, a signal processing module and a cold end temperature measuring module. The power supply module supplies power to the signal detection and processing module. The signal detection module comprises a sensing probe, a wiring identification circuit, a constant current source, a measuring circuit and an analog-to-digital conversion circuit. The sensing probe measures the measured temperature, the wiring identification circuit automatically judges a two-wire system, a three-wire system or a four-wire system and feeds back a result, the constant current source provides positive and negative constant current excitation, and the measuring circuit collects and processes feedback voltage and then sends the feedback voltage to the analog-to-digital conversion circuit. The analog-to-digital conversion circuit is connected with the signal processing module through the isolation module, and the signal processing module calls a corresponding algorithm according to a wiring identification result and outputs final temperature data. According to the invention, high-precision temperature measurement at the grade of + / -0.02 DEG C can be realized in the range of-200 DEG C to 850 DEG C under the three / four-wire system and low-speed sampling conditions.
Owner:JIASHAN FUDAN RESEARCH INSTITUTE

Sine constant current source excitation method for eddy current displacement sensor

The invention discloses an eddy current displacement sensor sine constant current source excitation method, and belongs to the technical field of sensor measurement and control. The method comprises the following steps: S1, generating positive and negative symmetric reference voltages through a reference voltage source circuit; s2, outputting a square wave control signal with adjustable frequency by the control chip, and driving a switching circuit to generate a square wave taking the positive and negative reference voltage as a level; s3, processing the square wave through a filter circuit to obtain a standard sine wave voltage signal; and S4, converting the sine voltage signal into sine constant current source excitation through a Howland current source circuit, and outputting the sine constant current source excitation to a sensor probe coil. According to the invention, through combination of digital control and analog conversion, the circuit structure is simplified, the cost is significantly reduced, and convenient adjustment of the output frequency and high stability and precision of the output current are realized at the same time.
Owner:HUNAN AEROSPACE ELECTROMECHANICAL EQUIP & SPECIAL MATERIAL INST

PT symmetrical hot-resistance MEMS wind speed and direction sensor

The invention discloses a PT symmetrical hot-pressing resistance MEMS wind speed and wind direction sensor. The sensor comprises four groups of PT symmetrical MEMS resonators which are orthogonally distributed and have hot-pressing resistance feedback; the PT symmetrical MEMS resonator comprises two cantilever beam resonators with completely same structures, a coupling spring beam connected with the two resonators, and a constant current source connected with one resonator, each cantilever resonator comprises two anchor areas, a wide beam connected with the anchor areas, a narrow beam with a piezoresistive effect, a warped thin plate structure and external electrodes located on the two sides of the thin plate structure. Wind speed and wind direction signals are converted into rigidity change of the resonator array through mechanical action by means of a warped thin plate structure, and the rigidity change enables the PT symmetrical MEMS system to deviate from an EP point, so that system frequency splitting is caused. As the frequency splitting quantity of the PT symmetric system is in direct proportion to the square root of the disturbance quantity, the wind speed and direction sensor can detect tiny wind speed signals, and has the advantages of very high sensitivity, simple process, high integration level and the like.
Owner:SOUTHEAST UNIV

Detection circuit based on NTC thermistor and heat conduction meter

The invention relates to the technical field of gas detection, in particular to a detection circuit based on an NTC thermistor and a heat conduction meter. The detection circuit based on the NTC thermistor comprises a main NTC thermistor which is suspended in air flow; the constant current source circuit is used for providing constant working current for the main NTC thermistor; the detection resistor is arranged between the main NTC thermistor and a ground node; the ADC sampling circuit is used for sampling analog voltages at two ends of the detection resistor into digital signals; the constant temperature adjusting circuit is used for controlling the magnitude of the current output by the constant current source circuit according to the voltage of the main NTC thermistor, so that the main NTC thermistor is kept at the target temperature; the temperature compensation circuit is used for detecting the temperature of the environment where the heat conduction measuring meter is located; and the processing unit is used for determining a detection result according to the digital signal and compensating the detection result according to the environment temperature. According to the detection circuit based on the NTC thermistor, the response speed and the measurement precision of measurement are improved.
Owner:JIANGSU JINGCHUANG ELECTRONICS

Overcurrent detection circuits, integrated devices, and battery management systems

The present disclosure provides an overcurrent detection circuit for detecting overcurrent conditions in a battery / battery pack during charging and discharging. The circuit controls the charging and discharging of the battery / battery pack via a charge control transistor and a discharge control transistor connected in series with the battery / battery pack. The drain of the charge control transistor is connected to the drain of the discharge control transistor. The overcurrent detection circuit includes: a first detection transistor and a second detection transistor; a first voltage acquisition circuit and a second voltage acquisition circuit; a constant current source; and a comparison unit. The present disclosure also provides an integrated device and a battery management system.
Owner:ZHUHAI MAIJU MICROELECTRONICS CO LTD

Integrity monitoring device and method for small-size metal sample in high-pressure environment

The invention discloses a device and a method for monitoring the integrity of a small-size metal sample in a high-pressure environment. An environment control system; the loading system comprises an electronic testing machine and a connecting rod, and the electronic testing machine loads a small-size metal sample installed in the high-pressure kettle in an electric insulation mode through the connecting rod to achieve stress or strain controlled loading; the electric signal measurement system comprises a constant current source, a current commutation device and a signal acquisition device. The constant current source applies a constant current to the small-size metal sample, the current reversing equipment switches the direction of the constant current at a preset frequency, and the signal acquisition equipment intermittently monitors voltage values at two ends of the small-size metal sample; and determining the integrity change of the small-size metal sample according to the change of the voltage value in the loading process. According to the invention, on-line monitoring of the integrity of the small-size metal sample is realized in a high-pressure environment.
Owner:INST OF CORROSION SCI & TECH +1

Laser welding control system and regulation and control method

The invention provides a laser welding control system and method.The system comprises a temperature feedback regulation and control module, a PLC control module, a half-bridge driving module and a constant-current source device.According to the system, an instruction is transmitted to the PLC control module on the basis of a temperature signal and a temperature state signal obtained through real-time monitoring of the temperature feedback regulation and control module; the PLC control module controls starting and stopping of a laser and a cooling system in the welding process according to different temperature state signals, when the temperature state signals are in the range lower than a laser PWM regulation starting threshold Tset and higher than a lowest temperature threshold Tmin, PWM regulation and control are conducted on the transmitting power of the laser, meanwhile, a constant current source circuit is started, and the laser is driven to weld through constant current; besides, on the basis of light beam space distribution calculation and high-temperature beam width and low-temperature beam width analysis, the optimal PWM duty ratio and frequency are solved through iterative optimization, stable welding quality is ensured, welding precision is improved, and welding defects are reduced.
Owner:SHANGHAI LONGSHU INFORMATION TECHNOLOGY CO LTD

Delay circuit and system applied to time-interleaved analog-to-digital converter

The invention provides a delay circuit applied to a time-interleaved analog-to-digital converter, the circuit comprises a first delay module, a second delay module and a delay selector, the first delay module is composed of multiple stages of delay units connected in series, each stage comprises a fixed inductor connected in series and a variable capacitor connected in parallel, and is used for providing large-range adjustable delay; the second delay module is connected to the output end of the first delay module and comprises a parallel combination of an adjustable constant current source and a programmable capacitor array, high-precision delay adjustment is achieved, the minimum adjustment step length of the second delay module is smaller than that of the first delay module, and multiple input ends of the delay selector are connected with output nodes of all stages of delay units respectively. The selection module is used for selecting coarse delay signals in different stages; the circuit realizes low-noise coarse delay adjustment through the inductance-capacitance network, completes high-precision fine delay adjustment by using current-capacitance combination, and has the advantages of wide delay range, high adjustment precision, low noise, good stability and the like.
Owner:CHONGQING GIGACHIP TECH CO LTD

Automatic temperature compensation circuit and method based on thermal flowmeter

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.
Owner:CHENGDU RUIBAO ELECTRONIC TECH CO LTD

Surge protector withstand voltage test system and method

The invention relates to a surge protector withstand voltage test system and method, and belongs to the technical field of surge protectors, the system comprises a test tool, the test tool comprises a tool body, a pneumatic execution component and a PCB function board, the tool body is made of bakelite, metal handles are arranged on the two sides of the tool body, and a detachable cover plate is fixed to the bottom of the tool body through hinges and lock catches; a wiring groove is formed in the inner side of the cover plate; the pneumatic execution component comprises a double-piston cylinder, a slide rail, a clamp assembly and an elastic conductive elastic needle; the double-piston cylinder drives the clamp assembly to linearly move along the X direction through the slide rail so as to clamp the surge protector to be tested; the elastic conductive elastic needle is fixed on the clamp assembly, the head of the elastic conductive elastic needle is in elastic contact with an exposed contact of the tested surge protector, and the tail of the elastic conductive elastic needle is connected to the PCB function board through a wire; the PCB function board comprises a high voltage constant current source circuit, a multipath relay switching circuit and an MCU control module.
Owner:BEIJING PINGHE CHUANGYE TECH DEV CO LTD

Lithium battery thermal runaway gas early warning system

The invention belongs to the technical field of new energy automobile lithium battery thermal runaway early warning, and particularly discloses a lithium battery thermal runaway gas early warning system. The method is used for solving the problem that thermal runaway cannot be rapidly and accurately detected and early warning cannot be carried out in advance in the existing monitoring technology. The early warning system comprises a main control unit, a core processing unit, a graphical user interface, a dual-frequency driving signal generation circuit, a spectral signal dual-frequency demodulation circuit, a temperature control circuit, a constant current source and overcurrent protection circuit, a spectral data acquisition circuit, a graphical user interface, an optical system, a gas sampling device and an early warning model. The power supply of the early warning system adopts a three-stage voltage reduction design, and comprises an AC-DC switching power supply, a DC-DC switching power supply and a low dropout regulator. Based on the off-axis integral cavity optical path coupling technology of the double-optical wedge group, the light beam angle is accurately adjusted through the double optical wedges of the stepping motor, a beam combiner does not need to be used, and the light energy utilization rate and the detection sensitivity are improved.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Magnetic field polarity monitoring system applied to plasma etching machine

The invention provides a magnetic field polarity monitoring system applied to a plasma etching machine, and relates to the technical field of magnetic field polarity monitoring, the magnetic field polarity monitoring system is used for monitoring whether the magnetic field polarity is successfully switched, the magnetic field polarity monitoring system comprises a controller, a coil and a constant current source device, the controller is configured to send a magnetic field polarity switching instruction to a power supply output circuit; the power output circuit is configured to output a target driving signal to the coil; the coil is configured to switch magnetic field polarity in the etching cavity in response to a target driving signal; and the polarity monitoring circuit is configured to monitor a target driving signal output by the power supply output circuit and feed back a magnetic field polarity switching result to the controller according to the target driving signal and the magnetic field polarity switching instruction. By adding the polarity monitoring circuit, active monitoring of the polarity of the output magnetic field of the constant-current source equipment can be realized, the output accuracy of the constant-current source equipment is improved, the working efficiency of the coil is improved, and the running safety of the constant-current source equipment and the coil is also improved.
Owner:SHENZHEN HUAXIN SEMICON EQUIP TECH CO LTD

Fault detector of accelerator switch assembly and detection method thereof

The invention discloses a fault detector of an accelerator switch assembly and a detection method thereof. The fault detector comprises at least one detection circuit. Each detection circuit comprises three constant current sources with equal output current, a first resistor and two voltage comparators; the input ends of the three constant current sources are used for inputting reference current; the output end of the first constant current source and the output end of the second constant current source are used for being connected with a normally-closed contact and a normally-open contact of an electric switch to be tested respectively, and the output end of the third constant current source is grounded through a first resistor. The common contact of the to-be-tested switch is grounded. Two input ends of the first voltage comparator are respectively connected with the output end of the first constant current source and the output end of the third constant current source; two input ends of the second voltage comparator are respectively connected with the output end of the second constant current source and the output end of the third constant current source; the output ends of the first voltage comparator and the second voltage comparator are used for outputting detection signals. According to the scheme, the detection efficiency and the detection precision of fault detection of the accelerator switch assembly can be greatly improved.
Owner:CHINA SOUTHERN AIRLINES CO LTD

Corrosion test device and method for fluctuation load stress of grillage spring

The invention discloses a grid spring fluctuation load stress corrosion test device and method. The device comprises a high-pressure kettle; an environment control system; the loading system comprises a loading tester and a loading pair, and the loading pair is used for applying constant deformation and fluctuation load to the grillage spring; the loading tester controls the loading pair to move in the high-pressure kettle until the loading pair is in contact with the grillage spring; the contact point measuring system comprises a constant voltage source and a first signal acquisition device, constant voltage is applied to the grillwork spring and the loading pair through the constant voltage source, and the first signal acquisition device monitors current abrupt change and determines a loading starting point; according to the integrity measuring system, a constant current source provides stable direct current, a current reversing device switches the current direction at a preset frequency, and a second signal collecting device monitors changes of electric signals at the two ends of the grillwork spring in real time and determines the complete state of the grillwork spring. According to the invention, accurate identification of the loading starting point of the grillage spring and real-time monitoring of the integrity state in the high-pressure environment are realized.
Owner:INST OF CORROSION SCI & TECH +1

Constant-current electrical stimulation system with impedance monitoring function and use method of constant-current electrical stimulation system

The invention discloses a constant-current electrical stimulation system with impedance monitoring and a use method thereof. The system comprises a main control unit, a digital isolator, a voltage-controlled constant current source circuit, a current acquisition circuit, an impedance detection circuit, a main power supply circuit, a power supply isolation module, a secondary power supply circuit, a booster circuit, an interaction host and the like which are connected in order. Safe and reliable pulse electrical stimulation output with adjustable parameters is provided, human tissue impedance and real-time current during stimulation are monitored in real time, an interaction host can display related information, and a user is warned when impedance or current is abnormal, so that accurate and safe electrical stimulation is realized.
Owner:XIAMEN BOCHUANG ZHONGYUAN MEDICAL TECH CO LTD

Matrix type plane temperature field monitoring system and method based on temperature-sensitive diodes

The invention discloses a matrix type temperature detection system and method based on temperature-sensitive diodes, the problems of complex wiring and large temperature drift of a traditional multi-node temperature measurement system are solved through M * N matrix layout, row and column time-sharing gating and constant current driving technologies, the system adopts an independent column constant current source to ensure the measurement consistency, and a high-precision ADC and a dynamic calibration algorithm are combined, so that the measurement accuracy is improved. And the precision of + / -0.2 DEG C is realized within the range of 50-150 DEG C. The method is particularly suitable for high-density temperature measurement scenes such as battery thermal management, electronic equipment overheating monitoring and the like.
Owner:SHANXI ZHITEXI NEW ENERGY TECHNOLOGY CO LTD

Interface Module for Charging and Discharging an Electrochemical Energy Store

An interface module for charging and discharging an electrochemical energy store for an electrical consumer, in particular for an electric-motor-powered vehicle, includes a first interface and at least one second interface that is electrically connected to the first interface. The first interface is designed, in particular of proprietary design, such that the interface module is connectable to a corresponding counterpart of the electrochemical energy store. The at least one second interface is of universal design such that the interface module is connectable to a corresponding counterpart interface of an external constant-voltage or constant-current source for the purpose of charging the electrochemical energy store. The at least one second interface is further connectable to a corresponding counterpart interface of a further electrical consumer for the purpose of discharging the electrochemical energy store.
Owner:ROBERT BOSCH GMBH

Air-free atmospheric temperature measuring device and air-free atmospheric temperature measuring method

The invention provides an overhead atmospheric temperature measuring device and method. The measuring device comprises at least one temperature probe and a temperature measuring circuit. The temperature probe adopts a patch type four-wire platinum resistor temperature sensor, spaceflight white paint is coated on the surface of the temperature probe and a nearby cable, and the temperature probe is arranged on the outer surface of the high-altitude balloon; the temperature measurement circuit adopts a four-wire system constant current source temperature measurement circuit and comprises a power conversion circuit, a constant current source circuit, a filter circuit and an instrument amplification circuit.
Owner:AEROSPACE INFORMATION RES INST CAS

Hot-pressing resistance PT symmetrical MEMS pressure sensor

The invention discloses a thermocompression resistance PT symmetrical MEMS pressure sensor, which comprises two resonators with identical structures, and the two resonators are connected through a group of coupling spring beams. Each resonator comprises four anchor areas connected with the thin film substrate, narrow beams which are connected with the four anchor areas and have a piezoresistive effect, and a mass block connected with the four narrow beams, and the four anchor areas are symmetrically distributed on the two sides of the mass block. For one of the resonators, a current path is formed through connection of a constant current source in the anchor section on the same side of the mass block. Under the action of a constant current source, hot resistance pressing feedback is generated at narrow beams of the resonators, so that the two coupled resonators form a PT symmetric system, and the PT symmetric resonators are initially arranged at an Exception Point (EP) point. When pressure acts on the lower surface of the substrate, the substrate generates strain, the position of the anchor area is driven to change, the rigidity of the resonator is changed, a PT symmetric system deviates from an EP point, the system eigenfrequency is split and shows pull-ratio oscillation, and the frequency splitting amount depends on the pressure borne by the substrate. Because the EP point has a large response to tiny disturbance, the thermal pressure resistance PT symmetric MEMS pressure sensor can realize accurate measurement of weak pressure change, and has the advantages of high sensitivity and simple manufacturing process.
Owner:SOUTHEAST UNIV

High-precision analog signal processing circuit based on multistage operational amplification

The invention discloses a high-precision analog signal processing circuit based on multi-stage operational amplification, which comprises a signal input conditioning module, a main amplification channel and a feedback regulation channel, and the core is to realize signal amplification, filtering and closed-loop control by using an operational amplifier. Precise processing and stable output of complex signals are achieved through differential input, multi-stage amplification, filtering shaping and closed-loop feedback. Signal precision, anti-interference performance and adaptability are effectively improved, and the method is suitable for constant current source feedback, precise instrument and industrial sensing signal processing and power equipment performance upgrading.
Owner:HANGYU POWER SYST (SHANGHAI) CO LTD

Adjustable constant current source power control circuit

The embodiment of the invention discloses an adjustable constant current source power control circuit, which is used for controlling the power of an adjustable constant current power supply and comprises a voltage sampling circuit, a divider circuit and a voltage selection circuit, the voltage sampling circuit is connected with the adjustable constant current source and is used for acquiring a first voltage from the adjustable constant current source according to a preset proportionality coefficient; the divider circuit is connected with the voltage sampling circuit and is used for calculating and dividing according to a preset reference voltage and the first voltage to obtain a second voltage; the voltage selection circuit is formed by connecting a first voltage follower and a second voltage follower in parallel, the first voltage follower is connected with the divider circuit and used for following a second voltage, the second voltage follower is used for following a third voltage, and the third voltage is determined according to a preset value; a selective switch is formed between the first voltage follower and the second voltage follower, and the selective switch is used for selecting the output of the first voltage follower or the output of the second voltage follower to be connected to the adjustable constant current source. According to the technical scheme provided by the invention, tedious designs of other circuits such as a PWM pulse width detection circuit and a maximum pulse limiting circuit are omitted, and the circuit has the characteristics of simplicity and high efficiency.
Owner:AUSTEN TECH BEIJING CO LTD

Constant current source generating circuit, row driving circuit, driving chip, display panel and device

The utility model provides a constant current source generation circuit, a row driving circuit, a driving chip, a display panel and a device. The constant current source generation circuit comprises a reference current generation unit used for switching an adjustment mode of a reference current according to a control signal, and generating and outputting the reference current with an adjustable current value according to the determined adjustment mode, the adjustment mode comprising determining the reference current according to a reference voltage and an external resistor or determining the reference current according to a built-in current source; the driving unit comprises a first current mirror group, is connected with the reference current generating unit and is used for outputting driving voltage and bias voltage of the first current mirror group; and the channel current output unit comprises a second current mirror group, the first current mirror group and the second current mirror group are matched to form a current mirror, the driving voltage and the bias voltage are provided for the second current mirror group, and the current mirror is used for carrying out mirror image processing on the reference current so as to output constant current source channel current. According to the invention, the current value adjusting range of the constant current source channel current is improved.
Owner:CHIPONE TECHNOLOGY (BEIJING) CO LTD

Detection circuit method suitable for various electricity utilization information acquisition terminals

The invention relates to the technical field of detection circuits suitable for various electricity utilization information acquisition terminals, and discloses a detection circuit method suitable for various electricity utilization information acquisition terminals. The method comprises the following steps: setting an environment temperature, calibrating a shunt resistor and a thermistor, constructing a three-order resistance-temperature mapping relation, and calculating thermal resistance and thermal response characteristics to realize accurate modeling; a thermistor is attached to a shunt resistor, heat-conducting silicone grease is added to form a thermal coupling structure, voltage is collected through a constant current source and a differential amplifier, a resistance value is converted into temperature in real time, instantaneous current is inversely calculated based on a heat balance equation, then energy integration and grade judgment is completed, and various electrical parameter indexes are output. According to the method, modeling, collection, conversion and inversion processes are integrated, a complete thermal-electric detection link is constructed, a traditional current sensor is not needed, and the method has the advantages of being compact in structure, low in cost, flexible in deployment and the like and is suitable for a low-power-consumption distributed terminal.
Owner:JIANGSU SUGONG ELECTRIC POWER TECHNOLOGY CO LTD

Control circuit for high-voltage switch

The invention relates to a control circuit for a high-voltage switch. The control circuit comprises a double-MOS high-voltage switch circuit and an integrated control circuit, the double-MOS high-voltage switch circuit comprises two stages of cascaded high-voltage MOS switch tubes; the integrated control circuit comprises a cross-voltage domain control circuit, a constant current source drive circuit and an overvoltage protection circuit. The cross-voltage-domain control circuit is used for converting an external control signal into a high-voltage-domain control signal; an output node of the constant current source driving circuit is connected with a grid electrode of the first-stage MOS tube and a grid electrode of the second-stage MOS tube, and the constant current source driving circuit is used for providing stable driving current through a constant current source according to a high-voltage domain control signal so as to control on-resistance of the first-stage MOS tube and on-resistance of the second-stage MOS tube; the overvoltage protection circuit is used for monitoring a high-voltage domain control signal in real time, and when the high-voltage domain control signal exceeds a safety threshold value, the first-stage MOS tube and the second-stage MOS tube are rapidly switched off, so that overvoltage damage is avoided. The high-voltage switching circuit can solve the problems of overlarge signal deviation and poor reliability caused by distortion of the high-voltage switching circuit, thereby ensuring that a chip can stably work in a high-voltage domain.
Owner:NO 24 RES INST OF CETC

Active heat dissipation system and method for LED lamp beads

The invention relates to the technical field of lamp bead active heat dissipation, and discloses an LED lamp bead active heat dissipation system and method, and the method comprises the steps: injecting a micro-current pulse into a PN junction of an LED chip through a constant current source, collecting a forward voltage drop sampling value, and collecting a substrate temperature sampling value; calculating a junction temperature value based on the forward voltage drop sampling value, and calculating a junction-to-case temperature difference value and a substrate temperature rise rate value; setting an early-warning state identifier when the junction-to-case temperature difference value exceeds an early-warning threshold value and the duration meets a preset duration, setting an alarm state identifier when the junction-to-case temperature difference value exceeds an alarm threshold value, and shielding thermal runaway detection when the substrate temperature rise rate value exceeds an environment thermal shock threshold value and the junction-to-case temperature difference value is smaller than an environment exclusion threshold value; when the state identification is the normal state identification, calculating a first compensation current value; and when the state identification is the early warning state identification, a second compensation current value is calculated, and when the state identification is the alarm state identification, an alarm current limiting value is calculated, so that the working stability and long-term reliability of the LED in a wide temperature range are ensured.
Owner:LIPU MEIYAD OPTOELECTONICS CO LTD

Wind turbine generator blade lightning protection intelligent detection system and method based on unmanned aerial vehicle

The invention discloses a wind turbine generator blade lightning protection intelligent detection system and method based on an unmanned aerial vehicle. The system comprises an unmanned aerial vehicle platform, a force and position hybrid control assembly, an electrical measurement unit and a ground data processing unit. The unmanned aerial vehicle carries the detection mechanism to fly to the position of the blade lightning arrester, stable contact is achieved through force sensing feedback, a constant current source applies a test current, the on resistance is measured, and data is returned in real time. And the ground unit filters, compensates and judges the multi-point measurement result to generate a conduction state report. The system can automatically complete lightning protection channel detection under an unattended condition, has the advantages of high detection precision, strong environmental adaptability, good safety, high efficiency and the like, and is suitable for rapid inspection and state evaluation of onshore and offshore wind turbine generators.
Owner:华电(宁夏)能源有限公司新能源分公司

Method and device for detecting insulation resistance of energy storage system, electronic equipment and storage medium

The invention discloses an energy storage system insulation resistance detection method and device, electronic equipment and a storage medium, and the method comprises the steps: employing an adjustable constant current source structure and a capacitance compensation circuit according to a dynamic compensation current unit, and achieving the dynamic compensation of a current in an energy storage system; according to the multi-band signal injection unit, a frequency sweep circuit is adopted to realize frequency sweep; and according to a cooperative control unit, cooperative control of the dynamic compensation current unit and the multi-band signal injection unit is adopted to realize insulation impedance detection. Through cooperative detection of the insulation impedance of the energy storage system based on dynamic direct current injection and capacitance compensation, the frequency sweeping technology is combined with dynamic current compensation, Y capacitance interference is solved, and the problem of signal crosstalk is solved through cooperative control.
Owner:SHANGHAI ZHIGUANG ELECTRIC POWER CO LTD

Dam anti-seepage body integrity detection method based on artificial power supply

The invention discloses a dam anti-seepage body integrity detection method based on an artificial power supply. Comprising the following steps: injecting a broadband excitation current signal into a dam anti-seepage body through a multi-frequency program control constant current source; a modular distributed electrode array is adopted to collect and obtain voltage data of the surface of the dam anti-seepage body in real time; high signal-to-noise ratio voltage data is obtained by adopting filtering processing and a digital phase-locked amplification technology; carrying out three-dimensional inversion calculation by adopting an improved electrical impedance tomography algorithm, and reconstructing an internal conductivity distribution image of the dam anti-seepage body; analyzing, identifying and positioning defects through a deep learning model; and constructing an electro-seepage coupling inversion model, converting the internal conductivity distribution image based on the dam anti-seepage body into permeability coefficient distribution, and generating an integrity evaluation report of the dam anti-seepage body. Compared with a traditional detection method, the method is high in detection precision, wide in application range and high in detection efficiency, and a brand new technical means is provided for evaluating the health state of the dam seepage-proofing body.
Owner:JIANGXI ACAD OF WATER RESOURCES (JIANGXI PROVINCE DAM SAFETY MANAGEMENT CENT JIANGXI PROVINCE WATER RESOURCES MANAGEMENT CENT)