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7223 results about "Dc voltage" patented technology

Method and device for detecting abnormal data of photovoltaic system

The invention discloses a photovoltaic system abnormal data detection method and device, and relates to an abnormal detection technology based on a multi-head self-attention mechanism fusion variational auto-encoder and a bidirectional long short-term memory network (BiLSTM). Abnormal detection of electrical parameters (including DC voltage and current and AC voltage and current), environment parameters (relative humidity, wind direction and wind speed) and system parameters (including inverter error codes, inverter environment temperature difference, module environment temperature difference and the like) in a photovoltaic system is realized. The invention discloses a photovoltaic system abnormal data detection method. The method comprises the following steps: (1) photovoltaic system data acquisition and data processing; (2) encoding time sequence data of the photovoltaic system; (3) data sampling and data feature enhancement; (4) data decoding operation; and (5) detecting an abnormal value of the photovoltaic system.
Owner:国网新疆电力有限公司营销服务中心

Direct current voltage divider parameter anomaly detection method based on harmonic characteristics

The invention discloses a DC voltage divider parameter anomaly detection method based on harmonic characteristics, and the method comprises the steps: deploying an isolation type voltage sensor at a bus of a DC power transmission system, carrying out the voltage sampling through combining with an ADC, carrying out the data buffering and preprocessing, extracting a fundamental wave component and a target harmonic component through the fast Fourier transform, and calculating the harmonic distortion rate. And constructing a low-voltage arm capacitance and harmonic distortion rate model based on a voltage divider secondary circuit equivalent circuit and an energy distribution principle, and calibrating the low-voltage arm capacitance and harmonic distortion rate model. And designing a multi-objective optimization scheduling algorithm based on energy storage capacity and capacitance characteristics, and realizing dynamic power distribution and harmonic suppression of the system. And after abnormal triggering, the system automatically loads a capacitance compensation coefficient, adaptively adjusts algorithm parameters in combination with a measurement loop PI control link, reduces a harmonic amplification effect, and ensures that a measurement error is within an acceptable range. Harmonic monitoring precision and capacitance compensation optimization capability of the direct-current power transmission system are effectively improved, and stable operation of the system is guaranteed.
Owner:NANJING INST OF MECHATRONIC TECH

Dual three-phase permanent magnet synchronous generator rectification system and direct current voltage stabilization control method thereof

The invention relates to a dual three-phase permanent magnet synchronous generator rectification system and a direct current voltage stabilization control method thereof. Comprising a dual three-phase permanent magnet synchronous generator, a VSD decoupling converter, a load current observer, a dynamic load feed-forward compensator, a voltage closed-loop controller, a dead-beat predictive current controller, a maximum four-vector SVPWM modulation module and a six-phase rectifier. The double-three-phase topological structure adopted by the invention has the advantages of multiple control degrees of freedom, high reliability and the like. A dynamic load feed-forward compensator is constructed to perform dynamic feed-forward compensation on quadrature-axis current of the motor, so that the recovery time of bus voltage is shortened, and the voltage fluctuation amplitude is reduced; the designed dead-beat predictive current controller optimizes the dynamic characteristics of a current loop, improves the torque tracking performance of the motor, and further improves the voltage stabilization regulation capability of the system. The designed load current observer realizes the analysis redundancy of current detection and improves the reliability of the system.
Owner:JIANGSU UNIV

Bidirectional DC-DC power supply active damping control system and method

The invention relates to the technical field of active damping control, and discloses a bidirectional DC-DC power supply active damping control system and method, and the system comprises a front-end AC input rectification module, an LLC resonant circuit, and a Buck converter module: the front-end AC input rectification module is used for converting an AC input voltage into a DC voltage; the LLC resonance circuit is used for inverting the rectified direct current voltage into alternating current with a set frequency and transmitting the alternating current to a secondary side through a transformer; and the Buck converter module is used for rectifying an alternating current signal and adjusting the alternating current signal into a required direct current output voltage, and further comprises an LC filter and an active damping control module. By adopting the active damping control method, the resonance peak caused by the LC filter can be effectively suppressed without additionally adding a physical resistor, so that the fluctuation of the output voltage is limited. According to the control strategy, the problems of power loss and heating caused by a traditional passive damping method are avoided, and the energy efficiency of the system is remarkably improved.
Owner:SUZHOU WANRUIDA MEASUREMENT & CONTROL TECHNOLOGY CO LTD

Alternating current fault ride-through control method of direct current sending-out system and storage device thereof

The invention provides an alternating-current fault ride-through control method of a direct-current sending-out system and storage equipment thereof. The method comprises the steps that the operation condition of a wind power flexible direct-current system is monitored in real time; when it is detected that the direct current side voltage of the wind power flexible direct current system is larger than a set threshold value at the receiving end converter station, a direct current side energy consumption device of the flexible direct current system is started to dissipate surplus power; when an alternating current fault is detected at the sending end converter station based on the direct current side voltage, the sending end converter station is switched to a current limiting mode, a fan and a power transmission system of the wind power flexible direct current system are controlled, and surplus power is dissipated again through an unloading circuit; when the AC voltage recovers, the sending-end converter station is adjusted back to a normal mode; and power transmission of the wind power flexible direct current system is recovered. According to the invention, on the basis of the operation condition of the receiving-end and sending-end converter station direct-current voltage monitoring system, the energy consumption device, the fan, the power transmission system and other links are used for cooperative control, power can be balanced, equipment can be protected, and the system stability can be enhanced.
Owner:ELECTRIC POWER RES INST CHINA SOUTHERN POWER GRID CO LTD +2

Clock signal generation circuit, wired communication transceiver, and electronic device

The invention provides a clock signal generating circuit, a wired communication transceiver and electronic equipment, and the circuit outputs a first DC voltage comprising phase difference information and frequency difference information of a reference clock signal and a feedback clock signal through a phase frequency detection module. The pulse generator generates a narrow pulse signal based on the DC voltage and a reference clock signal, the oscillation frequency of each secondary ring oscillator in the cross-coupled ring oscillator is controlled by the first DC voltage, and the cross-coupled loop performs synchronous coupling and phase sequence adjustment processing on each secondary ring oscillator. One output node in the cross coupling ring oscillator receives the narrow pulse signal, frequency and phase locking is completed in an injection locking mode, and the frequency divider is used for conducting frequency division processing on any high-frequency clock signal and outputting a feedback clock signal. Therefore, a high-frequency multi-phase clock signal with low phase noise and high phase precision can be generated by using the low-frequency reference clock signal.
Owner:FUDAN UNIVERSITY

Variable-frequency reconfigurable wireless power transmission system and parameter design method

The invention discloses a variable-frequency reconfigurable wireless electric energy transmission system and a parameter design method, and relates to a wireless electric energy transmission system and a parameter design method. The invention aims to solve the problems that the existing wireless power transmission technology is difficult to maintain approximately constant power transmission in the face of wider coupling coefficient fluctuation, and the system control complexity is higher at the same time. The system comprises a full-bridge inverter circuit, a primary side compensation network, a coupling coil, a secondary side compensation network and a rectification filter circuit. The input end of the full-bridge inverter circuit is connected with a direct-current voltage source UD, the output end of the full-bridge inverter circuit is connected with the input end of the primary side compensation network, the output end of the primary side compensation network is connected with the primary side input end of the coupling coil, and the secondary side output end of the coupling coil is connected with the input end of the secondary side compensation network. The output end of the secondary side compensation network is connected with the input end of the rectification filter circuit; the output end of the rectification filter circuit is connected with a battery load Ro. The invention belongs to the technical field of wireless power transmission.
Owner:HARBIN INST OF TECH +1

Fault ride-through test method of offshore wind power flexible direct output system

The invention discloses a fault ride-through test method for an offshore wind power flexible direct output system, and the method comprises the steps: building a fault equivalent circuit of the offshore wind power flexible direct output system, analyzing the operation characteristics of an AC power grid side under a low-voltage fault, and determining the incidence relation between the DC side excess energy and the power grid voltage drop; establishing a model representing each component in the fault equivalent circuit, wherein the components at least comprise a machine-side converter, a grid-side converter, a direct-current capacitor and an unloading resistor; when a low-voltage fault of an alternating-current power grid side is detected, executing the following cooperative control based on the model: synchronously starting unloading resistance control and reactive power support control, wherein an unloading resistor dissipates excess energy of a direct-current side through a direct-current chopper; the grid-side converter injects a capacitive reactive current which is deeply matched with the voltage drop of the power grid so as to improve the voltage of a grid-connected point; and if the direct-current voltage continuously exceeds the preset threshold value, starting power prompt drop control, and reducing the output power of the unit according to a gradient until the system recovers to be stable.
Owner:STATE GRID FUJIAN ELECTRIC POWER RES INST +2

Alternating current and direct current micro-grid layered distributed control method and system

The invention relates to the technical field of micro-grid control, and discloses an AC / DC micro-grid layered distributed control method and system, and the method comprises the steps: obtaining a DC voltage outputted by a distributed power supply in a DC micro-grid and an AC frequency outputted by a distributed power supply in an AC micro-grid, and carrying out the normalization processing; according to the voltage normalization value and the frequency normalization value, a finite time consistency algorithm is adopted to calculate a primary active power reference value of the interconnected converter; compensating the primary active power reference value according to a distributed secondary controller to obtain a secondary active power reference value; and generating a control signal of each interconnected converter according to the secondary active power reference value. Through hierarchical distributed control, the purposes that the total power sent by the direct current micro-grid and the alternating current micro-grid is proportionally distributed according to respective rated capacities and the active power transmitted by all the interconnected converters is proportionally distributed according to the transmission capacities are achieved, and the operation safety and stability of the alternating current and direct current micro-grid are effectively improved.
Owner:LISHUI POWER SUPPLY COMPANY OF STATE GRID ZHEJIANG ELECTRIC POWER

Low-modulation-ratio topological high-reliability high-voltage direct-hanging energy storage system and method

The invention provides a low-modulation-ratio topological high-reliability high-voltage direct-hanging energy storage system and method.The system comprises three phases of energy storage unit chains, each phase of energy storage unit chain is formed by cascading a plurality of energy storage units, and the connecting ends of the three phases of energy storage unit chains are sequentially connected with an alternating current side filter inductor in series and then connected with a power grid; the energy storage unit comprises an H-bridge power unit, a bus capacitor, a direct current side filter inductor, a battery side pre-charging device, a direct current side contactor and a battery cluster; the direct current side positive electrode of the H-bridge power unit is sequentially connected with the direct current side contactor, the battery side pre-charging device, the battery cluster and the direct current side filter inductor in series and then is connected with the direct current side negative electrode of the H-bridge power unit, and the alternating current side positive electrode of the H-bridge power unit is sequentially connected in series. According to the invention, the high-voltage direct-hanging energy storage system can fully utilize the DC voltage redundancy to realize the frequency doubling current suppression of the battery cluster by utilizing the low modulation ratio characteristic, and the ripple current pulsation amplitude of the battery meets the national standard requirement under the condition that the device cost is not increased.
Owner:SHANGHAI JIAOTONG UNIV

Metering anomaly detection method for direct-current charging pile

The invention provides a DC charging pile metering anomaly detection method, and belongs to the field of charging pile intelligent detection. The method comprises the following steps: acquiring a DC voltage signal, a DC current signal, a voltage ripple signal and a current ripple signal of a DC charging pile in real time; meanwhile, the temperature of a charging pile metering chip is obtained; inputting the data into the constructed and trained DC charging pile metering anomaly detection model, and outputting a state prediction result; the direct-current charging pile metering anomaly detection model is newly designed and comprises a time sequence convolution module, a time sequence enhancement module, a time sequence optimization module and a prediction output module, final anomaly detection is completed through cooperation of the four modules, meanwhile, a dynamic weight optimization strategy is designed to conduct joint training on the constructed modules, and the detection accuracy is improved. And the overall performance of the model is ensured to be optimal. According to the invention, subtle changes and abnormal modes in the measurement data of the DC charging pile can be more accurately captured, the detection precision and efficiency are improved, and the labor cost is saved.
Owner:东平县特种设备管理服务中心(东平县计量测试所)

Direct current control method and system for improving transient stability of grid-connected converter

The invention discloses a direct current control method and system for improving transient stability of a grid-connected converter, and the method comprises the steps: judging whether a power angle out-of-limit-based fault judgment module or a voltage out-of-limit-based fault judgment module has a voltage drop or phase jump fault or not when any one module judges that a power grid has a voltage drop or phase jump fault; processing an angular velocity control signal of a synchronous control link through a direct current port transient energy correction module, and performing temporary storage unbalanced power-oriented lifting and inertia correction-oriented lifting on a direct current voltage reference value; the voltage value of the direct-current port capacitor is compared with a direct-current voltage reference value, and is processed by the steady-state direct-current voltage control module to obtain a direct-current voltage control reference value; the output data of the converter at the common coupling point obtains a synchronous control signal according to a synchronous control link; and based on the synchronous control signal, an internal potential reference value is obtained according to an internal potential control link, and then a converter driving signal is generated. According to the invention, the stability problem of the grid-connected converter when the power grid has a transient fault can be effectively solved.
Owner:SOUTHEAST UNIV

Control system for a bi-directional totem-pole ac-dc converter

A control system for an AC-DC converter includes a mixed-signal power controller and first and second gate drivers. The controller has a digital module and an analog module. The analog module has a current sensor generating a current sense voltage based on a sensed switch current. The digital module has a DC voltage sensor generating a DC sense voltage based on a DC bus voltage, and an AC voltage sensor generating an AC sense voltage and a binary polarity signal based on the AC voltage. The digital module induces the first gate driver to output first and second control signals for controlling a high-side switch and a low-side switch of a current shaping half-bridge based on first and second clock signals and the comparator voltage, such that an inductor current flowing through an inductor is proportional to a current command value.
Owner:BING ZHONGHUI

Control method and system for improving SVG disturbance signal generation precision

The invention discloses a control method and system for improving SVG (Static Var Generator) disturbance signal generation precision, relates to the technical field of SVG disturbance signal generation, and solves the technical problem that a current disturbance signal generated by an SVG is difficult to meet the dynamic precision requirement required by multi-frequency impedance measurement. According to the technical scheme, disturbance signal attenuation caused by SVG direct-current voltage control is calculated through an observer, after phase compensation, the disturbance signal attenuation and a direct-current voltage given value are superposed to serve as outer loop input of a voltage controller, and the outer loop input is subtracted from direct-current voltage feedback; an outer ring output is obtained through a voltage controller of an outer ring and superposed with an instruction current disturbance signal to serve as an inner ring input of a current controller, and SVG operation is controlled through a current inner ring controller and a PWM modulation instruction. The influence of a direct-current voltage outer loop on actual current disturbance signals is remarkably reduced, and the SVG can still output accurate actual current disturbance signals when instruction current disturbance signals of all frequencies are injected into the SVG.
Owner:CHINA UNIV OF MINING & TECH

Direct-current voltage self-balancing method in high-low voltage ride-through process of high-voltage frequency converter

The invention discloses a direct-current voltage self-balancing method in the high-low voltage ride-through process of a high-voltage frequency converter, and the method comprises the steps: obtaining an electric signal of the high-voltage frequency converter, calculating the Lyapunov index of a system in real time based on the electric signal, so as to quantify the chaotic state of the system, and generating a real-time Lyapunov index sequence; according to the real-time Lyapunov index sequence, the gradient of the real-time Lyapunov index sequence relative to a preset system state variable is determined, and a Lyapunov gradient field is constructed; using the Lyapunov gradient field to generate a basic control quantity through nonlinear mapping; and converting the basic control quantity into a pulse width modulation parameter to form a PWM control signal set to be applied to the high-voltage frequency converter. According to the method, the Lyapunov gradient field is constructed to provide prospective direction guidance for control, so that the chaotic oscillation is quickly suppressed, and the dynamic stability of the system under power grid disturbance is remarkably improved.
Owner:安徽华赛能源科技股份有限公司 +2

Cooperative ride-through control method under receiving end fault of new energy flexible direct output system

The invention discloses a cooperative ride-through control method for a new energy flexible direct current transmission system under a receiving end fault, and relates to the technical field of flexible direct current transmission, and the method comprises the steps: periodically collecting the grid-connected point voltage of a receiving end converter station, an output active current reference value, and the real-time data of the online impedance estimation of a converter station side; calculating the minimum possible true values of the converter station side equivalent reactance and the short circuit point voltage; calculating a reactive current reference value and an active current reference value of the flexible DC receiving end converter station after the fault occurs; calculating the input time of the energy consumption resistor; the reactive current reference value, the active current reference value and the energy consumption resistor input moment are sent to a receiving end converter station; and when the receiving-end converter station detects that the voltage drop of the grid-connected point meets the low-voltage crossing starting condition, the receiving-end converter station enters a low-voltage crossing control mode and starts control, and the receiving-end converter station performs corresponding adjustment. By the adoption of the method, the rising speed of the direct-current voltage is reduced fundamentally, the input time or the input frequency of an energy consumption device is reduced, and the economical efficiency of fault ride-through is improved.
Owner:NORTH CHINA ELECTRIC POWER UNIV

Array substrate and display device

InactiveCN114879422AAvoid Coupling CapacitorsAvoid flickering bad displaysNon-linear opticsCapacitanceInsulation layer
The invention provides an array substrate and a display device, and the array substrate comprises a substrate; the gate insulating layer is arranged on the substrate; the data line is arranged on the gate insulating layer; the first passivation layer is arranged on the gate insulation layer and covers the data line; the first shielding electrode is arranged on the first passivation layer, and the first shielding electrode is connected with the direct-current voltage signal output end; the second passivation layer is arranged on the first passivation layer and covers the first shielding electrode; the common electrode is arranged on the second passivation layer, and a part of the common electrode is overlapped with the data line and the first shielding electrode; the pixel electrode and the common electrode are arranged on the same layer or stacked, and the pixel electrode is insulated from the common electrode. The first shielding electrode is connected to the direct-current voltage signal, so that the data voltage signal on the data line does not affect the signal on the common electrode, coupling capacitance between the common electrode and the data line is avoided, and poor display of picture flicker is avoided.
Owner:GUANGZHOU CHINA STAR OPTOELECTRONICS SEMICON DISPLAY TECH CO LTD

DC voltage adaptive coordinated control system and method under fault of VSC-HVDC receiving-end power grid

The present invention belongs to the field of smart grids, and relates to a DC voltage adaptive coordinated control system and method under fault of a VSC-HVDC receiving-end power grid. The present invention checks the MSR and compares it with the expected fastest fault clearance time to provide key activation conditions for the active power control of an SEC. When DC overvoltage is prevented, the active power regulation of the SEC and a dynamic brake resistor is reduced by optimizing the control activation thresholds and reference values of the SEC and a REC.
Owner:TIANJIN UNIV

Variable-frequency reconfigurable wireless power transmission system and parameter design method

The invention discloses a variable-frequency reconfigurable wireless electric energy transmission system and a parameter design method, and relates to a wireless electric energy transmission system and a parameter design method. The invention aims to solve the problem that approximately constant power transmission is difficult to maintain in the prior art for relatively wide coupling coefficient fluctuation. The system comprises a full-bridge inverter circuit, a primary side compensation network, a coupling coil, a secondary side compensation network and a rectification filter circuit. The input end of the full-bridge inverter circuit is connected with a direct-current voltage source UD, the output end of the full-bridge inverter circuit is connected with the input end of the primary side compensation network, the output end of the primary side compensation network is connected with the primary side input end of the coupling coil, and the secondary side output end of the coupling coil is connected with the input end of the secondary side compensation network. The output end of the secondary side compensation network is connected with the input end of the rectification filter circuit, and the output end of the rectification filter circuit is connected with the battery load Ro. The invention belongs to the technical field of wireless power transmission.
Owner:HARBIN INST OF TECH +1

Direct-current electric energy meter self-calibration method and system

The invention provides a direct-current electric energy meter self-calibration method and system. The method comprises the following steps: acquiring an internal high-precision low-temperature drift voltage reference signal; converting the voltage reference signal into an analog calibration voltage signal on a sampling resistor by controlling a direct current standard voltage generation circuit according to the voltage reference signal; converting the voltage reference signal into an analog calibration current signal in a current loop by controlling a DC voltage-current conversion circuit according to the voltage reference signal; obtaining a current environment temperature, and calculating a calibration gain at the current temperature according to a preset temperature coefficient; according to a theoretical calibration value, calculating a voltage gain, a current gain and a power gain of the sampling voltage value and the sampling current value, and writing the gains into a memory; and correcting the reference voltage signal according to the obtained temperature calibration gain, and performing temperature compensation.
Owner:JIANGSU LINYANG ENERGY CO LTD

Modular converter for vehicle-to-vehicle charging

A converter system, e.g., for vehicle-to-vehicle charging, includes galvanically-isolated modular first and second converters having the same maximum voltage rating, a direct current (DC) voltage bus interconnecting the converters, and an electronic controller. An input voltage to the DC bus is converted into an output voltage via switching control signals to the modular converters. The system's voltage rating may equal the maximum of the input and / or output voltage, or it may equal the maximum input voltage and be about 50-percent of the maximum output voltage. The maximum input and output voltages may be equal. When the voltage rating is about 50-percent of the maximum input voltage, capacitors may be connected in parallel with the modular converters on an input side thereof. Switching circuits may be connected to the bus to control the conversion of the input voltage via switching control signals.
Owner:GM GLOBAL TECHNOLOGY OPERATIONS LLC

Multi-network converter current coordinated distribution and voltage optimization control method considering nonlinearity and negative sequence load

The invention discloses a current coordinated distribution and voltage optimization control method of a multi-network converter considering nonlinearity and negative sequence load. The method comprises the following steps: carrying out harmonic separation on three-phase load side current and three-phase capacitor voltage through feedforward compensation to obtain a fundamental wave positive sequence component, a fundamental wave negative sequence component and an h-order harmonic component; fundamental wave positive sequence active and reactive power are solved, and angular frequency and output voltage are respectively obtained through an active frequency regulator and a reactive voltage regulator; virtual impedance of a fundamental wave positive sequence, a fundamental wave negative sequence and a harmonic component is set, a multi-frequency-point virtual impedance voltage drop instruction is calculated, and a voltage reference instruction value is obtained by subtracting the multi-frequency-point virtual impedance voltage drop instruction value from the output voltage of the constructed network type converter; calculating a three-phase modulation wave signal based on the voltage reference instruction value, the capacitor voltage, the load side current, the inductor current and the DC voltage; and calculating a pulse signal of the switching device based on the three-phase modulated wave signal. The virtual impedance of the networking converter is set to be a negative value, the harmonic voltage drop on a common coupling point can be reduced, the sum of the virtual impedance and the actual impedance is adjusted to be a certain proportion, and the harmonic current of each order of the multi-networking converter can be distributed according to the proportion.
Owner:ZHEJIANG UNIV OF TECH

Coordination control method for energy storage and flexible multi-state switch in power distribution network system

The invention discloses a coordination control method for energy storage and a flexible multi-state switch in a power distribution network system, and relates to the field of power supply and distribution. The hierarchical control mode is adopted to coordinate the energy storage system and the flexible multi-state switch; the coordination control layer performs working mode selection and switching in a networking operation mode by a centralized controller according to the feeder load power, the charge state of a storage battery, the operation state of each transformer and the position and the number of feeder faults; the control strategy of the flexible multi-state switch can be changed among a constant DC voltage control strategy, a constant power control strategy and a droop control strategy; the control strategy of the storage battery can be switched among constant-current charging control, floating charging control and constant-voltage control; and the feeder load in the equipment control layer can also realize a load switching control strategy. By adopting the coordination control method, the power supply reliability and the power quality of the system can be improved.
Owner:이너 몽골리아 일렉트릭 파워 그룹 컴퍼니 리미티드 이너 몽골리아 일렉트릭 파워 리서치 인스티튜트 브랜치

Direct-current side voltage reference value setting method and apparatus, storage medium, and device

The present invention discloses a direct-current side voltage reference value setting method and apparatus, a storage medium, and a device. During low-voltage ride-through, direct-current side operation characteristics under different power grid voltage drop conditions are carefully considered. On the basis of different power grid voltage drop conditions, a corresponding strategy is executed to reduce a direct-current voltage reference value, so that a high modulation factor can be maintained during an entire low-voltage ride-through process, switching loss of a grid-forming converter can be reduced, and output waveform quality can be improved. During high-voltage ride-through, because constant-voltage control is adopted, the grid-forming converter may lose balance points. Therefore, according to differences in power grid voltage rise amplitude, the present invention divides a direct-current side reference value setting algorithm into three conditions, and provides an algorithm for maintaining a minimum active current required to stabilize a bus voltage of the direct-current side, so as to ensure that direct-current voltage remains controllable during the entire ride-through process.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO LTD RESEARCH INSTITUTE +2

Downselector for Sensing Electrode Voltages in an Implantable Stimulator Device

Sensing circuitry for an implantable stimulator device is disclosed. The sensing circuitry includes a downselector with switching networks used to couple selected electrode nodes and / or DC voltages to one or more sense amps. The switching networks comprise high-voltage devices that are controlled in accordance with a high-voltage power supply voltage VH. VH may be generated by a boost circuit, and may be set to the higher of a boosted voltage and a compliance voltage that powers the stimulation circuitry. The switching networks include three switches, some of which may comprise transfer gates. The downselector can be controlled to couple one or more electrodes nodes to a particular sense amp during sensing durations. The downselector can also be controlled during stimulation durations to couple one or more electrodes nodes together, thus supplementing operation of the stimulation circuitry.
Owner:BOSTON SCI NEUROMODULATION CORP

Operation control method and system of self-synchronizing voltage source centralized photovoltaic inverter

The invention provides a stable operation control method and system for a self-synchronizing voltage source centralized photovoltaic inverter, and the method comprises the steps: detecting the change rate of the DC voltage of the centralized photovoltaic inverter and the output active power of a photovoltaic panel in real time, and when the ratio of the change rate of the DC voltage to the change rate of the output active power of the photovoltaic panel exceeds a threshold value, starting the control of the stable operation of the photovoltaic inverter. A system working mode is converted from a power control mode to a voltage control mode, and a power given value and a direct-current voltage given value of a control system are adjusted in real time. A synchronous angular frequency is obtained by adding an output value of the deviation of the active power through a proportional controller and a power grid frequency value, and the phase of an output modulation voltage of a grid-connected converter is obtained after integration, so that the grid-connected power of the photovoltaic inverter is adjusted. The working points of the photovoltaic inverter can stably operate on all the working points of the photovoltaic power-voltage characteristic curve, it is ensured that the photovoltaic inverter is located at the maximum power point all the time, and then stable operation control over the self-synchronizing voltage source centralized photovoltaic inverter is achieved.
Owner:SHANGHAI JIAOTONG UNIV +1

Control method of composite direct-current power synchronization grid-following type converter

The invention discloses a control method for a composite direct-current power synchronization grid-following type converter, and belongs to the technical field of wind power grid-connected converter control. The problem that in the prior art, a traditional converter control method based on network tracking type control is low in stability due to subsynchronous oscillation easily generated under a weak power grid is solved. According to the method, the direct-current power of the grid-following type converter is collected and sequentially passes through a lead / lag link and an integral controller, then an obtained compensation item is introduced to a d-axis current reference instruction value output by a direct-current voltage loop, d-axis current and q-axis voltage are influenced, the influenced q-axis voltage serves as phase-locked loop input, and the phase-locked loop is connected with a phase-locked loop. An output grid-connected angle is directly controlled by a proportional-integral controller of a phase-locked loop link, and an angle small signal value additionally introduced by composite direct-current power synchronization is equivalent to that a network-forming type direct-current inertia synchronization link is introduced into a network-following type phase-locked loop. The method improves the adaptability of the following network type control system to the weak power grid, and can be applied to converter control.
Owner:HARBIN INST OF TECH

DC power distribution system and control power generation device

Voltage command values are set according to voltage fluctuations of a plurality of power supply sources, and one of outputs from a plurality of power supply circuits which output DC voltages obtained by performing conversion according to the voltage command values is supplied to a power conversion circuit as control power so that the system can be continuously operated even at the time of an abnormality due to a device failure and a power outage, and control power consumption can be suppressed in the case of voltage fluctuations of the power supply sources.
Owner:MITSUBISHI ELECTRIC CORP

Electrical system for a motor vehicle

This relates to an electric system for a motor vehicle, the vehicle including at least one power supply battery, the electric system including an electric charger intended to be connected, on the one hand, to the battery and, on the other hand, to an electric network outside the vehicle supplying an AC voltage or to electric equipment, and a microcontroller, the charger being able to charge the battery from an external electric network or to allow the battery to power the equipment, the charger including a DC-DC voltage converter able to operate in a first operating mode and a second operating mode, the microcontroller is characterized in that it is configured to control the activation of the first operating mode and to control the activation of the second operating mode.
Owner:VITESCO TECHNOLOGIES GMBH

Multi-modulation-format vector signal modulator based on microwave photonics

The invention discloses a multi-modulation-format vector signal modulator based on microwave photonics, and relates to the field of microwave photonics. Comprising an IQ quadrature modulation module, a continuous wave laser, a first power optical splitter, an optical carrier frequency generation module, a polarization beam combiner, an optical amplifier, a polarization beam splitter and a photoelectric balance detector module, the IQ quadrature modulation module comprises a double-parallel Mach-Zehnder modulator, a first forming filter, a second forming filter, a first attenuator, a second attenuator, a first direct current voltage stabilization source and a second direct current voltage stabilization source. According to the invention, the formed and filtered IQ baseband signal is input into the double-parallel Mach-Zehnder modulator for quadrature modulation, the IQ baseband signal and the other path of optical carrier signal subjected to differential MZM frequency multiplication are subjected to polarization beam combination, and then the signal is converted into a radio frequency signal through PD, so that the generation of a high-frequency-band and multi-modulation-format vector signal is realized, and the high-frequency-band multi-modulation-format vector signal is suitable for the fields of high-speed communication, photon radar and the like.
Owner:SOUTHEAST UNIV