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2604 results about "Current source" patented technology

A current source is an electronic circuit that delivers or absorbs an electric current which is independent of the voltage across it. A current source is the dual of a voltage source. The term current sink is sometimes used for sources fed from a negative voltage supply. Figure 1 shows the schematic symbol for an ideal current source driving a resistive load. There are two types. An independent current source (or sink) delivers a constant current. A dependent current source delivers a current which is proportional to some other voltage or current in the circuit.

Orbitronics device having orbital hall effect or inverse orbital hall effect, and method for enhancing efficiency thereof

The present disclosure provides an orbitronic device having orbital Hall effect or inverse orbital Hall effect, and method for enhancing the efficiency thereof. The orbital torque device comprises: a ferromagnetic / non-magnetic heterojunction formed by compounding a ferromagnetic layer and a non-magnetic layer as an orbital current source, wherein the ferromagnetic layer contains a ferromagnetic material, the non-magnetic layer contains a non-magnetic material with weak spin-orbit coupling, the non-magnetic layer is used as an orbital Hall channel to generate orbital current, and the orbital current enters the ferromagnetic layer, so that an orbital torque is generated through an orbital-spin conversion effect of the ferromagnetic layer to realize switching of a magnetic moment. The present disclosure can provide orbitronic device with low cost and good performance.
Owner:TIANJIN POLYTECHNIC UNIV

Circuit device and electronic device

A circuit device includes a current source circuit, a first charging circuit that supplies a first charging current to a charging node, a second charging circuit that supplies a second charging current to the charging node, and a control circuit that sets a current value of the first charging current and the second charging current, based on a current setting value. When the current setting value is in a first range, the first charging circuit supplies the first charging current. When the current setting value is in a second range on a higher current side, the second charging circuit supplies the second charging current. At switching between the first range and the second range, the first charging circuit supplies the first charging current and the second charging circuit supplies the second charging current.
Owner:SEIKO EPSON CORP

CONTROL DEVICE, OPTICAL SYSTEM AND LITHOGRAPHING PLANT

A control device (100) for controlling a number N, with N ≥ 1, of actuators (200) for actuating N optical elements of an optical system, comprising a control node (K2) coupling to the actuator (200) for providing a control voltage (V2) for the actuator (200), an amplifier (110) configured to receive a supply voltage (V1) provided at an input node (K1) and to provide an output voltage (V3) at an output node (K3), wherein the amplifier (110) comprises a plurality M, with M ≥ 2, of current sources (111, 112) comprising at least one charge-controlled current source (112) and a holding capacitor (113) for maintaining the level of the provided output voltage (V3), and a buffer coupled between the output node (K3) and the control node (K2). (120), which is designed to,to decouple the control node (K2) from the output node (K3) and to provide the control voltage (V2) for the actuator (200) based on the level of the output voltage (V3) of the holding capacitor (113).
Owner:CARL ZEISS SMT GMBH

Low-phase noise annular voltage-controlled oscillator based on multiphase injection locking

The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking, relates to the technical field of integrated circuits, and is used for solving the technical problems that an existing injection locking oscillator limits the frequency tuning range and cannot effectively suppress noise. The invention discloses a low-phase noise ring voltage-controlled oscillator based on multiphase injection locking. The low-phase noise ring voltage-controlled oscillator comprises a first ring oscillator unit and a second ring oscillator unit, the n first ring oscillator units are connected in series to form a chain structure; the second ring oscillator unit is provided with a cross coupling inverter complementary injection unit and a tail current source injection unit; a first output end of the chain structure is connected with a second input end of the second ring oscillator unit, and a second output end of the chain structure is connected with a first input end of the second ring oscillator unit; a first signal is injected into a cross-coupling inverter complementary injection unit and a tail current source injection unit, and a second ring oscillator unit receives a second signal output by a chain structure and then outputs a third signal.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Lightning arrester leakage ammeter self-calibration method and system

The invention relates to a lightning arrester leakage ammeter self-calibration method and system, and the method comprises the following steps: disconnecting a main leakage ammeter from an external main measurement loop, and closing a calibration loop of a redundancy calibration sensor and a reference current source after a preset time is delayed; controlling a reference current source to output standard signals with different current magnitudes, collecting the standard signals by using a redundancy calibration sensor, extracting effective signal components, and performing environment compensation; iteratively calculating a relative error between the effective signal component and the standard signal, if the relative error is less than or equal to a second threshold value, updating a calibration coefficient according to a ratio of the standard signal to the effective signal component, and correcting a measurement result of the main leakage ammeter based on the calibration coefficient; if the relative error is greater than a third threshold value, locking output and uploading fault information; otherwise, recording as one exception, and carrying out maintenance early warning according to the number of exceptions. Compared with the prior art, the self-checking and real-time calibration of the leakage ammeter of the lightning arrester can be completed on the premise of not influencing the operation of power equipment.
Owner:STATE GRID SHANGHAI MUNICIPAL ELECTRIC POWER CO

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

Current source type LCCL double-frequency resonance system and parameter matching method thereof

The invention discloses a current source type LCCL double-frequency resonance system and a parameter matching method thereof, which are suitable for synchronous double-frequency induction quenching of complex workpieces such as gears. The system is composed of two current type resonant inverters working at a low frequency and a high frequency respectively and a dual-frequency LCCL resonant cavity, and dual-frequency current superposition is realized through parallel output. The double-frequency LCCL resonant cavity has two parallel resonance points, a mode based on simplified topology is adopted to simplify parameter design, and meanwhile design errors are maintained at a low level. A power matching coefficient is introduced, the ratio of high-frequency output power to low-frequency output power is adjusted by adjusting the value of the power matching coefficient, and the problem of double-frequency power unbalance caused by frequency variation characteristics of load equivalent resistance and the like is solved. The superposed double-frequency current forms a low-frequency envelope embedded high-frequency oscillation composite waveform on the induction heating coil, cooperative control of tooth root deep quenching (low frequency) and tooth surface hard quenching (high frequency) is achieved, and the method has the advantages of being simple in parameter design, high in power decoupling performance, high in operation stability and the like.
Owner:HUNAN UNIV

Method for evaluating temporary overvoltage of system under asymmetric fault

The invention provides a system temporary overvoltage evaluation method under an asymmetric fault, and relates to the field of power systems, and the method comprises the steps: responding to a VSC grid-connected system AC fault, carrying out the equivalence of a VSC fault ride-through reactive power support strategy in a positive sequence network, carrying out the equivalence of a VSC unbalanced voltage suppression strategy in a negative sequence network, and carrying out the equivalence of the VSC fault ride-through reactive power support strategy in the negative sequence network; obtaining a single-machine equivalent model; the single-machine equivalent model is merged into a network admittance matrix, a corrected admittance matrix is constructed, and a corrected impedance matrix is solved; setting short-circuit boundary conditions, calculating short-circuit current increment of a fault point as an equivalent current source, solving voltage increment of each PCC point according to the corrected impedance matrix and the equivalent current source, and synthesizing three-phase voltage; and forming a TOV evaluation result based on the phase voltage maximum value of each PCC point, and calculating a voltage safety index according to the result. According to the invention, comprehensive analysis and evaluation of the temporary overvoltage risk of the new energy grid-connected system are realized.
Owner:NORTHWEST BRANCH OF STATE GRID POWER GRID CO

Method of circuit simulation

A circuit simulation method partitions circuits into linear and nonlinear subcircuits, obtains frequency responses of the linear portion, and applies causality-enforcing corrections to eliminate non-physical artifacts from band-limited data. The corrected responses enable construction of equivalent circuit models using voltage / current sources with passive elements, where source values update via convolution with port histories. This approach improves simulation accuracy and stability compared to direct frequency-inverse methods while maintaining compatibility with standard platforms including SPICE, PSCAD, and Simulink. Applications include power system transients, RF circuits, and high-speed digital interfaces.
Owner:HAIKOU SHIKONG MAILUO TECHNOLOGY CO LTD

IO port hot plug application circuit and device

The invention provides an IO port hot plug application circuit and device, and the circuit comprises a pull-down driving module which comprises an MOS tube Mn0, a capacitor C1 and a current source, and the capacitor C1 is connected in parallel between a grid electrode and a source electrode of the MOS tube Mn0; the current source is connected to the grid electrode of the MOS tube Mn0 and provides charging and discharging current for the capacitor C1; the drain electrode of the MOS tube Mn0 is connected with an SCL or SDA signal line, and the source electrode of the MOS tube Mn0 is grounded; the positive input end of the comparator CMP is connected with a reference level, and the negative input end of the comparator CMP is connected with an SDA or SCL signal line; the digital control system comprises a feedback loop of a main switch signal Hjen of a hot plug process and a real-time driving signal Hjctrl of an MOS (Metal Oxide Semiconductor) tube of an analog circuit; the output end of the pull-down driving module is connected with the IO interface, the output end of the comparator CMP is connected to the signal detection end of the digital control system, and the Hjctrl signal end of the digital control system is connected to the control end of the pull-down driving module.
Owner:SHANGHAI SHENXILING MICROELECTRONICS TECH CO LTD

Variable slew-rate current source gate drivers for hybrid power modules

In one aspect of the disclosure, a variable-current gate driver includes a plurality of inputs for receiving pulse-width-modulation (PWM) control signals transmitted from a processing system. Current sources controlled based on the pulse-width modulation (PWM) signals are coupled to respective gates of at least two transistors of a hybrid switch in the power module (PM) including different semiconductor technologies. The current sources are coupled respectively to at least one other non-gate terminal of the transistors. The current sources provide the slew rate control of the PM using variable current values to compensate for differences in the at least two semiconductor technologies in real-time to reduce switching losses and maximize efficiency.
Owner:GM GLOBAL TECHNOLOGY OPERATIONS LLC

Self-calibrating driver circuit

A self-calibrating driver circuit (100, 300, 400, 500, 700) for a laser diode is disclosed. The circuit comprises a configurable current source (105, 305, 405, 505), a current mirror (115, 315, 415) configured to mirror a current from the configurable current source to a first transistor (120, 320, 420, 520, 720) and to a second transistor (125, 325, 425, 725), and a control circuit (140, 340, 440). The control circuit is configured to monitor a current through the first transistor at a first time, and to configure the current source based on the current through the first transistor to provide a desired current to the second transistor for driving the laser diode at a subsequent second time. A radiation-emitting device comprising one or more of the self-calibrating driver circuits and at least one radiation-emitting element is also disclosed.
Owner:AMS OSRAM ASIA PACIFIC PTE LTD

Battery management system and monitoring devices

A monitoring device is provided. The monitoring device comprises one or more circuitry operable to obtain measurements of one or more pins of a battery system, the one or more circuitry comprising at least one circuit for monitoring current, which comprise: at least one other circuit for amplifying variance comprising at least one differential amplifier, one voltage reference in electrical connection with a first input of the differential amplifier; at least one transconductance means comprising at least one output in electrical connection with a second input of the differential amplifier and at least one input in electrical connection with an output of the differential amplifier; at least one current source in electrical connection with at least one output of the at least one transconductance means; and an output in electrical connection with at least one output of the at least one transconductance means.
Owner:DUKOSI

Methods and apparatus to regulate a common mode voltage of an amplifier

An example apparatus includes: current source circuitry having a first terminal, a second terminal, a third terminal, and a fourth terminal; current sink circuitry having a first terminal, a second terminal, a third terminal, and a fourth terminal; common mode voltage circuitry having a first terminal and a second terminal, the first terminal of the common mode voltage circuitry coupled to the first terminal of the current source circuitry and the first terminal of the current sink circuitry, the second terminal of the common mode voltage circuitry coupled to the second terminal of the current source circuitry and the second terminal of the current sink circuitry; idle current source circuitry having a terminal coupled to the third terminal of the current source circuitry; and feedback current source circuitry having a terminal coupled to the fourth terminal of the current source circuitry.
Owner:TEXAS INSTRUMENTS INC

Method and system for analyzing transient stability in fault stage of tracking-constructing network type converter series-parallel system

The invention relates to the technical field of new energy grid-connected control, in particular to a fault stage transient stability analysis method and system for a following-constructed network type converter series-parallel system, and the method comprises the steps: enabling a constructed network type converter to be equivalent to a controlled voltage source series impedance, enabling a following network type converter to be equivalent to a controlled current source, and enabling the controlled current source to be equivalent to a controlled voltage source series impedance; the whole series-parallel system is equivalent to a scene in which double voltage sources and a single current source are jointly connected in parallel to a PCC point, and a series-parallel system model is constructed; according to the series-parallel system model, respectively representing an active power coupling term of the network-building type converter and a voltage coupling term of the network-following type converter under the condition of considering parallel connection of the network-following type converter and the network-building type converter; according to the coupling term, remodeling an active loop control structure of the network-constructing converter and a phase-locked loop synchronization structure of the network-following converter, and obtaining a transient analysis model of the series-parallel system considering the coupling term; the transient stability of the hybrid system in the power grid fault stage is analyzed through the transient analysis model, and the influence on the transient stability is effectively represented.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO LTD RESEARCH INSTITUTE +3

Method for calculating sensitivity of influence of multiple control parameters of multiple stations on short-circuit current of alternating current system

PendingCN121791144AImprove short-circuit current control capabilitiesImprove controlSingle network parallel feeding arrangementsFault locationControl engineeringPower grid
The invention discloses a method for calculating the influence sensitivity of multiple stations and multiple control parameters on the short-circuit current of an alternating current system, and the method comprises the steps: building a calculation data model of the short-circuit current of a power grid, and enabling the model to comprise at least one new energy or energy storage device equivalent to a controlled current source; based on the calculation data model and the independent variable selected by each station, utilizing an iteration method to calculate the short-circuit current increment of each station; calculating the short-circuit current of each station fault point according to the short-circuit current increment; and calculating a sensitivity index of the independent variable relative to the short-circuit current of the specified fault point according to the short-circuit current.
Owner:CHINA ELECTRIC POWER RESEARCH INSTITUTE CO LTD

Voltage-to-delay converter

A voltage-to-delay converter includes a first reset transistor having a first terminal coupled to a power supply terminal, a gate terminal receiving a reset signal, and a second terminal coupled to a top plate of a first integrating capacitor, and a second reset transistor having a first terminal coupled to a power supply terminal, a gate terminal receiving the reset signal, and a second terminal coupled to a top plate of a second integrating capacitor. First and second input transistors receive first and second input voltages, and are coupled between the top plate of the first and second integrating capacitors, respectively, and a first current source. A discharge current source is coupled to bottom plates of the first and second integrating capacitors. A pulse generator has first and second inputs coupled to the top plate of the first and second integrating capacitors, respectively.
Owner:TEXAS INSTRUMENTS INC

Digital player volume lossless control method and digital player

PendingCN121011212ASignal processing for reducing noiseRecord information storageNoiseReference current
The invention relates to the technical field of digital playing equipment, and provides a lossless control method for the volume of a digital player and the digital player. The method comprises the following steps of: after receiving a target volume parameter, executing dynamic multiplying power oversampling and high-order noise shaping on an input digital audio signal, and injecting preset jitter to suppress in-band quantization distortion so as to generate an optimized digital audio stream; meanwhile, a high-resolution digital reference current control instruction corresponding to the target volume is independently generated, output of a reference current source is adjusted according to the high-resolution digital reference current control instruction, and a high-precision differential current signal is obtained by combining nonlinearity, temperature excursion and quantization errors of a closed-loop feedback compensation device through a multi-bit current segmentation network; performing bias stabilization processing on the signal, and converting the signal into a differential voltage signal for suppressing common-mode noise through a precision differential resistance network; and finally, low-distortion differential analog audio signals capable of directly driving a load are output through low-distortion gain, impedance conversion and power driving, so that low-distortion, high-signal-to-noise-ratio and wide-dynamic-range output in a full-volume range is realized.
Owner:SHENZHEN UNIWISDOM TECHNOLOGIES CO LTD

Second Order Intermodulation Injection for Non-linearity Cancellation

An electronic device may include wireless circuitry. The wireless circuitry can include a first input transistor, a first capacitance neutralization having a source terminal coupled to a tail node, and a second order intermodulation generation circuit configured to produce second order intermodulation signals at the tail node. The wireless circuitry can further include a second input transistor and a second capacitance neutralization transistor having a source terminal coupled to the tail node. The first and second capacitance neutralization transistors can be cross-coupled with the input transistors. A fixed or adjustable current source can be coupled to the tail node. The second order intermodulation generation circuit can include a transistor biased in a weak inversion mode.
Owner:APPLE INC

PSASP-based electromechanical transient modeling method for network-building converter

The invention belongs to the technical field of electromechanical transient modeling, and particularly discloses a PSASP-based electromechanical transient modeling method for a network-building converter, and the method comprises the steps: setting the voltage of a grid-connected point and an equivalent impedance parameter of a converter transformer; the method comprises the following steps: in a PSASP custom modeling platform, establishing a network construction type converter control model, and obtaining a reference voltage signal through the control model; performing voltage-current conversion to obtain a real part and an imaginary part of current injected into the bus; setting a virtual impedance link in a control model of the network-forming converter, calculating virtual voltage drop by combining a current real part and an imaginary part with a virtual impedance parameter, correcting a reference voltage signal, and performing voltage-current conversion to obtain the corrected current real part and imaginary part; and injecting the corrected real part and imaginary part of the current into a PSASP bus in a current source form, and establishing an electromechanical transient model of the grid-forming converter.
Owner:SHANDONG UNIV +1

System and method for geomagnetic compensation and bias magnetic field generation for cold atom interference

The invention provides a geomagnetic compensation and bias magnetic field generation system and method for cold atom interference. The system comprises a triaxial magnetometer, a triaxial Helmholtz coil, a voltage-controlled current source and an FPGA regulation and control module. The three-axis magnetometer is used for collecting space magnetic field data at a plurality of monitoring positions in the space where the three-axis Helmholtz coil is located in real time; the FPGA regulation and control module is used for calculating control voltage data required by the voltage-controlled current source according to a target magnetic field and any space magnetic field data collected by the three-axis magnetometer in each sampling period, controlling coil current transmitted to the three-axis Helmholtz coil, and outputting the coil current to the three-axis Helmholtz coil. And loop iteration is carried out until the three-axis Helmholtz coil generates a target magnetic field at a plurality of monitoring positions, wherein the target magnetic field is a near-zero magnetic field in the X / Y direction, and the magnetic field intensity in the Z direction is constant and is a non-zero value. The device can respond to the change of the environmental magnetic field in real time, and provides a stable and accurate magnetic field environment for the cold atom interference test on the basis of compensating the influence brought by the geomagnetic field.
Owner:长沙量子测量产业技术研究院有限公司

Multi-machine common-bus generator system stator grounding fault active arc extinction method based on online calculation of ground capacitance parameters

The invention discloses a multi-machine common-bus generator system stator grounding fault active arc extinction method based on online calculation of ground capacitance parameters, and the method comprises the following steps: S1, connecting a controllable current source in parallel with a secondary side of a generator neutral point grounding transformer, and injecting current into a neutral point; extracting a voltage component with the same frequency as the injection current, and calculating a ground capacitance parameter of the generator system on line through the voltage component and the injection current value; s2, measuring the three-phase phase voltage of the generator and the phase value of the zero-sequence current at the generator end of the generator, and solving the fundamental wave potential of a fault point based on the measured value; deriving a compensation current needing to be injected at the generator end side of the fault phase generator, and injecting the compensation current at the generator end; and S3, after compensating current is injected into the generator ends to realize arc extinguishing of fault points, measuring the generator end zero-sequence current phase of each generator again, and performing fault selective positioning, thereby determining a fault unit in the multi-generator common-mother system. According to the method, effective arc extinction can be realized, and the fault unit can be reliably judged.
Owner:NORTH CHINA ELECTRIC POWER UNIV +1

Circuit of high-voltage amplification system based on photoelectric coupler and high-voltage amplification system

The invention relates to the technical field of high-voltage amplifiers, in particular to a circuit of a high-voltage amplification system based on a photoelectric coupler and the high-voltage amplification system. The circuit comprises a control circuit used for generating a driving signal according to an input signal; the input end of the first current source and the input end of the second current source are both connected with the output end of the control circuit; the input end of the first photoelectric coupler is connected with the output end of the first current source; the input end of the first photoelectric coupler is connected with the output end of the second current source; and the high-voltage output circuit comprises an upper bridge arm module and a lower bridge arm module which are connected in series.
Owner:DALIAN TAISMAN TECH CO LTD

Power converter for dynamically adjusting voltage headroom based on current

A power converter for dynamically adjusting voltage headroom based on a current is provided. The power converter includes a high-side switch, a low-side switch, a sensor circuit, a current source, a mirror circuit, a reference voltage adjusting circuit and a control circuit. The sensor circuit senses a current flowing through a power receiving component to output a sensed current to a first terminal of a first transistor of a current mirror. A first terminal of the second transistor of the current mirror is connected to the current source. The reference voltage adjusting circuit sets a reference voltage according to a current from a node between the first terminal of the second transistor and the current source. The control circuit controls the high-side switch and the low-side switch according to the reference voltage.
Owner:ANPEC ELECTRONICS CORPORATION

Direct-driven wind mechanism grid type-following grid type dual-mode switching control method and system based on grid side-machine side converter control conversion

The invention belongs to the field of power system control, and discloses a direct-driven wind turbine generator network type-following network type dual-mode switching control method and system based on network side-machine side converter control conversion. According to the method, on the basis that grid-connected stability of the direct-driven fan is maintained, the control capability of a grid-side converter and a machine-side converter is fully combined, and the control capability of the direct-driven fan as a voltage source and a current source is excavated, so that when a voltage short-circuit ratio is changed due to access of large-scale new energy, the voltage short-circuit ratio is changed. The grid-connected flexibility and control free undisturbed switching of the direct-driven fan can be realized, and the grid-connected stability and adaptive capacity of the direct-driven wind power plant are improved.
Owner:STATE GRID HUBEI ELECTRIC POWER CO LTD +1

Control circuit of voltage converter, chip and electronic equipment

The embodiment of the invention provides a control circuit of a voltage converter, a chip and electronic equipment. The control circuit of the voltage converter comprises a reference current generation circuit and a driving control circuit, the reference current generation circuit is configured to generate a minimum reference current according to the bias current source under a light load condition, generate an enhanced current according to a differential voltage of a reference voltage and a feedback voltage under a heavy load condition, and generate a target reference current in combination with the minimum reference current, and the target reference current is greater than the minimum reference current; the driving control circuit is configured to control the second power switch tube to be turned off when the inductance sampling current rises to a high-order comparison threshold value, the inductance sampling current is the sampling current of the inductance current of the voltage converter, and the high-order comparison threshold value is the sum of the minimum reference current and a preset current hysteresis window; and when the inductance sampling current is reduced to the target reference current, the second power switch tube is controlled to be conducted. The circuit realizes light-load ultra-low power consumption, heavy-load transient response and stable voltage regulation and control.
Owner:ZHUHAI NANXIN SEMICON TECH CO LTD

Testing device and interface resistivity detection method

The embodiment of the invention provides a testing device and an interface resistivity detection method, and relates to the field of semiconductors. The testing device is used for detecting a to-be-tested sample. The testing device comprises a sample table, and an image detection device, a first detection device and a second detection device which are arranged on the sample table, the testing device further comprises a current source, a voltage detection device and a processor. The current source and the voltage detection device are connected with the first detection device and the second detection device. Wherein the image detection device is used for acquiring an image of a to-be-detected sample placed on the sample table; the processor is used for controlling the first detection device to be in contact with a first electrode in the to-be-detected sample and controlling the second detection device to be in contact with a second electrode in the to-be-detected sample according to the image, displayed by the image detection device, of the to-be-detected sample; the current source is used for providing constant current for the to-be-tested sample; the voltage detection device is used for detecting a voltage value between the first electrode and the second electrode of the to-be-detected sample.
Owner:HUAWEI TECH CO LTD +1

Oscillator circuit for PWM controller

The invention belongs to the technical field of electronic circuits, and particularly relates to an oscillator circuit for a PWM controller. Comprising an oscillator module which comprises a feedback loop and a current detection circuit; the hiccup module is used for gating and outputting an input signal by a data selector according to the level of the input PWM logic control signal so as to control the on-off of a transmission gate, establishing a charging and discharging process and providing a delay starting function for the oscillator module; and the jittering frequency module outputs current sources Iref0 of different sizes by performing combined gating on a current source I'ref and current sources I1-I4, outputs four paths of current sources Iref1-Iref4 of different sizes through a current mirror array mirror image, and provides charging and discharging current for the oscillator module and the hiccup module. By dynamically adjusting the PWM frequency, the switching frequency is matched with the load requirement, the invalid switching frequency is reduced, and the power consumption is greatly reduced.
Owner:WUXI I CORE ELECTRONICS

Composite voltage generation device and cable insulation performance evaluation system and method

The invention discloses a composite voltage generation device and a cable insulation performance evaluation system and method, and relates to the technical field of high-voltage insulation testing. The composite voltage generating device comprises a synchronous controller, a direct current source, an impact source, an IGBT active protection unit and a magnetic isolation coupler, and by means of the excellent characteristics of the IGBT and the magnetic isolation coupler, the superposition time sequence accuracy of direct current and impact voltage is improved, and waveform distortion is reduced. The IGBT active protection unit comprises a first IGBT and a second IGBT, and direct-current voltage polarity switching can be realized through selective conduction of the IGBTs; the RC circuit is connected in parallel between the collector electrode of the first IGBT and the emitter electrode of the second IGBT, reverse current flowing back to the direct current source direction can be discharged through the RC circuit, the risk of energy flowing back is reduced, meanwhile, the magnetic isolation coupler can completely block direct current, and an impact source is protected against the influence of direct current voltage; according to the invention, the authenticity and reliability of cable insulation performance evaluation can be effectively improved.
Owner:ELECTRIC POWER RES INST CHINA SOUTHERN POWER GRID CO LTD

Quenching detection sensor based on high-temperature superconducting material and detection method

The invention belongs to the technical field of high-temperature superconducting detection, and discloses a quench detection sensor based on a high-temperature superconducting material and a detection method.The quench detection sensor comprises an inner layer structure composed of a metal base band, a first insulating layer and a high-temperature superconducting material layer, and a second insulating layer arranged between the metal base band and the high-temperature superconducting material layer; the second insulating layer covers the areas, not at the two ends, of the outer side of the inner layer structure, and a metal base band or a high-temperature superconducting material layer is arranged between the second insulating layer and the first insulating layer; the two ends of the short-circuit connection metal are fixedly connected to the first end of the metal base band and the first end of the high-temperature superconducting material layer respectively; the number of the connecting terminals is two, the two connecting terminals are jointly used for being connected with a detection voltmeter and a detection current source through wires, and the two connecting terminals are fixedly connected to the second end of the metal base band and the second end of the high-temperature superconducting material layer respectively. The quench detection sensor is high in detection reliability.
Owner:SOUTHWESTERN INST OF PHYSICS