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2310 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.

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

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

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

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

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

CAN-FD wake-up circuit, CAN transceiver and electronic equipment

The invention provides a CAN-FD wake-up circuit, a CAN transceiver and an electronic device, the CAN-FD wake-up circuit comprises a level shift module, an amplification comparison module and a wake-up identification module, the differential input end of the amplification comparison module is the source electrode of an NMOS tube, and the source electrode of the NMOS tube allows input of negative voltage, so the level shift module can process a CAN low level signal in a negative voltage range, and the wake-up identification module can process the CAN low level signal in the negative voltage range. Therefore, the input common-mode level range of the wake-up circuit of the CAN-FD is improved. On-off of the first switch is controlled based on whether the CAN transceiver is in a dormant state or a working state so as to control access of the second current source, and the output current of the second current source is a plurality of times of the output current of the first current source so as to increase the bandwidth of the amplification comparison module in the working state. Therefore, the amplification comparison module can be simultaneously applied to the dormant state and the working state of the CAN transceiver, so that the circuit cost is reduced.
Owner:GUANGDONG HONGYIXIN AUTOMOTIVE ELECTRONIC TECH CO LTD

Quick response control method and system for transient stability of power system

The invention discloses an electric power system transient stability rapid response control method and system, and relates to the technical field of electric power systems, and the method comprises the steps: collecting a transient harmonic current signal generated by a power grid fault in real time through a harmonic detection unit connected to a DC bus of an energy storage converter, and calculating the phase offset of the transient harmonic current signal; generating a power control instruction through a pre-configured hardware mapping circuit based on the phase offset; acquiring a current differential signal by using a power grid line current sensor, and identifying a path of transient energy flowing to a key unit based on a power grid topological structure; for the path, dynamically forming a virtual high-impedance wall on the target line; and on a consumption path predefined according to the power grid topological structure, controlling the energy storage converter to operate in a current source mode and configuring a reverse power characteristic so as to absorb the energy flow turned by the virtual high-impedance wall.
Owner:STATE GRID GANSU ELECTRIC POWER CO JIUQUAN POWER SUPPLY CO

Grounding grid fault diagnosis method and system based on EVO-MNR algorithm

The invention relates to a grounding grid fault diagnosis method and system based on an EVO-MNR algorithm, and the method comprises the steps: obtaining all accessible nodes based on a grounding grid topological structure, randomly selecting two accessible nodes, injecting an excitation current source into a grounding grid in turn, measuring and calculating the voltages of other accessible nodes, and obtaining a measurement value and a calculation value; taking the residual error of the measured value and the calculated value as a target function, and solving a first optimal solution of the grounding grid branch resistance by using an EVO algorithm; obtaining corresponding resistance value distribution based on the first optimal solution, and solving a corresponding calculation value based on the distribution; a target function value is calculated based on the corresponding calculation value, if the calculated target function value is smaller than a preset value, the first optimal solution is the optimal solution, otherwise, the target function is improved by using an MNR method to obtain an improved target function, and the optimal solution of the grounding grid branch resistance is solved based on the improved target function; and determining a fault branch based on the optimal solution. Compared with the prior art, the grounding grid fault can be quickly and accurately diagnosed.
Owner:STATE GRID SHANGHAI MUNICIPAL ELECTRIC POWER CO

Clock delay circuit for reducing interleaving distortion of time interleaving pipeline ADC (Analog to Digital Converter)

The invention relates to a clock delay circuit for reducing interleaving distortion of a time interleaving pipeline ADC, and belongs to the field of analog-to-digital converters. Comprising a four-channel time-interleaved sampling switched capacitor array, an allowance amplifier module and four groups of delay control circuits, the four-channel time-interleaved sampling switched capacitor array comprises four sampling switched capacitor arrays which are connected in parallel; the four sampling switch capacitor arrays connected in parallel are all communicated with the allowance amplifier module; each group of delay control circuits is correspondingly connected with one sampling switch capacitor array; the delay control circuit comprises a clock generation circuit and a programmable current source array; the programmable current source array is connected with the clock generation circuit; the output end of the clock generation circuit is connected with the corresponding sampling switch capacitor array; according to the invention, the effect of reducing interleaving distortion in the four-channel time-interleaving pipeline analog-to-digital converter is realized, and the performance of the whole analog-to-digital converter is further improved.
Owner:BEIJING MICROELECTRONICS TECH INST

Bridgeless power factor correction circuit for reducing electromagnetic interference

A bridgeless power factor correction (PFC) circuit for reducing electromagnetic interference (EMI) is disclosed herein. A current source is placed in parallel with a switch of a low frequency leg. The current source may be turned on during zero crossings of the AC input voltage to limit current and reduce the rate of change in voltage. In turn, EMI may be advantageously reduced without the need for large passive filters or complicated circuitry.
Owner:POWER INTEGRATIONS INC

Rapid three-dimensional electromagnetic simulation method and verification device for large uninsulated coil

The invention discloses a rapid three-dimensional electromagnetic simulation method and verification device for a large-scale uninsulated coil, and aims to solve the problems of large calculation load, difficulty in homogenization, poor field-circuit coupling convergence and low result precision of the three-dimensional simulation of the existing large-scale uninsulated coil. The simulation method comprises the following steps: establishing a homogenized coil which does not divide specific turns, and setting anisotropic resistivity; constructing a current source area intercepted on the coil body and a free turn-to-turn resistance area connected in parallel with the current source area; applying current source excitation according to an open loop / closed loop coil; and the precision is ensured through radial grid encryption and result convergence verification. The verification device comprises a three-dimensional multi-turn verification coil, a direct current source, a multi-direction alternating external field applying module and a voltage and magnetic field measuring unit, direct current is supplied, an alternating external field is applied, and the simulation accuracy is measured and verified in real time. The method is simplified in modeling, rapid in calculation, good in convergence and high in precision, adapts to open-loop / closed-loop and single-cake / multi-cake coils, and is suitable for large uninsulated superconducting coils in rotary and linear motors, nuclear fusion equipment and the like.
Owner:CHINA YANGTZE POWER

Superconductor magnet systems and methods for generating magnetic fields

A superconductor magnet system including a superconductor magnet including a plurality of field coils connected in series, each field coil having a plurality of turns including superconductor material. The system also includes a primary electric current source connected across the plurality of the field coils for supplying a DC electric current to the field coils to generate a magnetic field. The system further includes a secondary electric current source connected in parallel with the primary electric current source across a subset of the field coils for supplying an additional DC electric current to the or each field coil in the subset to modify or correct the magnetic field.
Owner:TOKAMAK ENERGY

Fault ride-through method based on hybrid synchronous control voltage / current source mode switching

The invention relates to a fault ride-through method based on hybrid synchronous control voltage / current source mode switching, aiming at fault ride-through (FRT) challenge in a novel power system, and breaking through the limitation of the existing solution from three key dimensions of overcurrent limitation, fault synchronization and reactive power support. On the basis of a hybrid synchronous control strategy, the damping characteristic of the system is remarkably improved, and the synchronous stability of the inverter during the fault period is effectively guaranteed; meanwhile, the intelligent control of smooth mode switching can be completed without complex switching logic or power grid information by utilizing simple detection of a saturation signal of a current limiter and combining with a mixed voltage / current source control architecture. Besides, the method has excellent short-circuit ratio (SCR) adaptive capacity, stable operation can be kept under different power grid strength conditions, and an innovative solution is provided for friendly improvement of new energy grid connection and transient performance optimization of a power system.
Owner:CENT SOUTH UNIV

Charge pump circuit for phase-locked loop, charge pump module, phase-locked loop and communication chip

The invention belongs to the field of integrated circuits, and particularly relates to a charge pump circuit for a phase-locked loop, a charge pump module, the phase-locked loop and a communication chip. The charge pump circuit adopts a source switch single-end topology, and a numerical control current source DAC with an adaptive compensation circuit and two rail-to-rail operational amplifiers are applied. According to the source electrode switch single-end topology, the switch time sequence is dynamically optimized through a three-state working mode, and the charge injection effect and clock feed-through interference are remarkably reduced; the numerical control current source realizes multi-stage high-precision programmable current output according to a control code, responds to the change of output voltage in real time by utilizing a self-adaptive compensation mechanism, and maintains the stability of charging and discharging current; the rail-to-rail operational amplifier eliminates the common-mode constraint in a full-swing input range by connecting an NMOS-PMOS differential pair structure in parallel. The charge pump circuit overcomes the defects of a charge pump circuit adopted in an existing phase-locked loop in the aspects of output swing, stability and the like, static power consumption can be reduced to the microampere level, and the advantages are obvious.
Owner:ANHUI UNIV +1

Pre-emphasis buffer systems and related methods

Implementations of a pre-emphasis signal processing system may include an output driver which may include a pre-emphasis transistor coupled with a steady state transistor, where gates of the pre-emphasis transistor and steady state transistor may be coupled together. The system may include a regulator voltage input coupled to a source of the pre-emphasis transistor; a first resistor coupled between a drain of the pre-emphasis transistor and an output of the output driver; and a second resistor coupled between the drain of the steady state transistor and the output of the output driver; and a pre-emphasis source including a current source coupled to a delay transistor, the delay transistor coupled with the output of the output driver.
Owner:SEMICON COMPONENTS IND LLC