3254 results about "Voltage control" patented technology

The invention discloses a fault ride-through hierarchical control method for a network-constructed converter, and the method comprises the steps: introducing a virtual resistor formed by fault current negative feedback into the voltage and current inner loop control of the network-constructed converter based on VSG control through a current inner loop dynamic amplitude limiting control layer after the converter enters a fault ride-through state, the size of the virtual resistor is adjusted in real time along with the amplitude of the fault current so as to carry out dynamic current limiting control on the virtual resistor; and the power outer loop dynamic compensation control layer dynamically adjusts an active power instruction value and a reactive power instruction value of the network construction type converter based on VSG control during the fault ride-through period according to the voltage drop degree of the power grid after the converter enters the fault ride-through state. And respectively performing active-frequency control and reactive-voltage control based on the active power instruction value and the reactive power instruction value. In addition, the method also comprises a state coupling and parameter self-adaption module. According to the method, the GFM converter can have better dynamic performance in the fault recovery stage.

The invention belongs to the technical field of virtual power plants, and particularly relates to a distribution network virtual power plant aggregation control method based on a disperse complex adaptive system, which comprises the following steps: constructing a distribution network disperse complex adaptive system architecture comprising a tail end resource layer, a local autonomy layer and a global collaboration layer; setting a dynamic aggregation index of the virtual power plant, and calculating the dynamic aggregation index of the virtual power plant based on the operation data of the distributed resources in the local autonomous layer; a virtual power plant dynamic aggregation algorithm based on a greedy strategy is adopted, and a virtual power plant is formed through aggregation; a virtual power plant voltage control strategy based on key node selection is constructed, in the local autonomy layer, each virtual power plant preferentially controls internal resources to realize autonomy, and in the global collaboration layer, key node voltage in each virtual power plant is adjusted to realize collaboration control among the virtual power plants. According to the method, the adjustment potential of the distributed resources can be fully mined, so that the distributed resources can better participate in power grid adjustment, and resource utilization and power grid benefit maximization are realized.

The invention discloses a tracking-network construction combined low-voltage ride-through control method based on transient support. The method comprises the following steps: S1, analyzing transient voltage characteristics and requirements of a network construction-tracking network converter; s2, analyzing a transient voltage support target of the network construction-network following type hybrid multi-machine system; s3, constructing a network construction-network following type hybrid multi-machine system control strategy; and S4, on the basis of the network construction-network following type hybrid multi-machine system control strategy constructed in the S3, optimizing the low voltage ride-through control of the network following type converter and the transient voltage control of the network construction type converter. According to the control method disclosed by the invention, the advantages of the network-building / network-following converter are complemented, the control between the network-building / network-following converter and the network-building / network-following converter is coordinated, and the transient voltage of the power grid is actively supported by using the multi-machine converter system.

The invention discloses a PLC scheduling algorithm based on a multi-core soft real-time operating system, and relates to the technical field of voltage control, and the algorithm comprises the following four steps: 1, starting a target industrial control system, completing hardware self-inspection, memory allocation and communication module starting, and sending an initialization ready signal after confirming that an assembly is normal; 2, according to PLC task functions and real-time performance, four types of standardized tasks are divided, priority levels are defined, sub-priorities are configured, a dependency relationship is identified, and a task chain is established; 3, counting the number of tasks and task chains, distributing resources by using multiple binding cores, and constructing a global ready queue to adapt to dynamic scheduling; and 4, monitoring an interrupt event through an interrupt manager, realizing high-priority task preemption by semaphores, and allocating tasks to corresponding CPU cores, so that the problems of soft real-time multi-core task preemption and data conflict are solved, the scheduling real-time performance and the data security are improved, the system failure rate is reduced, and the industrial control efficiency and stability are improved.

An active-reactive voltage cooperative control method for multiple reactive compensation devices considering energy storage comprises the steps that 1, simulation analysis is conducted on time sequence voltage fluctuation characteristics of a high-permeability photovoltaic grid-connected system, and dynamic influences of photovoltaic output fluctuation in different time periods on system node voltage are quantitatively evaluated; 2, solving a non-dominated solution set of the model by adopting a multi-target particle swarm optimization algorithm, realizing collaborative optimization and trade-off analysis of multi-dimensional performance indexes, and establishing a reactive power regulation model and an energy storage active power support model; and organically coupling the reactive power regulation model and the energy storage active power support model. By means of the method, high photovoltaic area voltage treatment can be effectively carried out in real time, and the method has high engineering application value and wide popularization prospects.

The invention discloses a multi-point voltage comprehensive control system and method for a photovoltaic high-permeability power distribution network. Comprising a photovoltaic output and load data acquisition module, a space-time coupling voltage sensitivity dynamic graph convolution calculation module, a source-load cooperative probability prediction module, a digital twin mapping module, a distributed feeder automation 5G cooperative control module and a voltage control execution module. The method comprises the following steps: collecting real-time data, calculating a multi-moment voltage sensitivity matrix through dynamic graph convolution, simulating multi-scene voltage distribution in a digital twin in combination with a source load probability prediction result, generating an optimization regulation instruction through 5G cooperative control, and controlling equipment to realize multi-point voltage regulation. According to the method, the sensing precision of photovoltaic and load changes, the voltage simulation accuracy and the control response efficiency are greatly improved, the voltage regulation stability and reliability of the power distribution network are comprehensively improved, and safe operation of the power distribution network under the photovoltaic high permeability is guaranteed.

The invention provides a photovoltaic access power distribution network voltage stability evaluation method, which comprises the following steps: acquiring ship docking time, staying duration and crane working frequency in a port area in real time, fusing obtained meteorological information, identifying a photovoltaic power generation output power change trend, and obtaining a daily power load peak-valley time period and a load fluctuation amplitude; according to the adjusted voltage value of each node, generating a switch operation instruction and a power adjustment instruction of the shore power supply equipment, identifying load abrupt change by executing the instructions, and determining a real-time power dispatching scheme by combining the power adjustment instruction and the ship arrival time; and according to the target voltage control value, determining the power utilization safety state of the port power distribution network, and evaluating the voltage stability of the photovoltaic access power distribution network through the operation data of the photovoltaic power generation access point.

The invention discloses a cooperative control system for an input-series output-parallel dual-active-bridge inverter, and relates to the technical field of power electronic converter control, an input voltage equalizing control IVSC loop is set for m-1 DAB sub-modules, and input voltage equalization of the DAB sub-modules is realized by adjusting phase shift angles of the sub-modules; an output voltage control OVC loop is set for the output DC bus voltage of the whole ISOP-DAB system to stabilize the DC bus voltage, a PIR controller is adopted in the OVC loop, and the resonant frequency is set to be twice of the fundamental frequency of the AC side, so that selective high gain is provided at the position, the frequency doubling fluctuation of the DC bus voltage is inhibited, and the frequency doubling fluctuation of the DC bus voltage is inhibited. According to the method and the device, the regulation quantity of the IVSC loop and the regulation quantity of the OVC loop are superposed to carry out cooperative control, so that the effective suppression of the frequency doubling fluctuation of the DC bus voltage and the automatic equalization of the power of each module are accurately realized on the premise of not increasing the hardware complexity.

The invention relates to the technical field of new energy automobile electric control, and discloses a self-adaptive voltage dynamic stability control method for a new energy automobile converter. The method comprises the following steps: acquiring a real-time voltage time sequence data sequence of the new energy automobile converter in an operation period; performing voltage disturbance characteristic analysis on the real-time voltage time sequence data sequence based on a rated voltage interval of the converter, and identifying voltage disturbance modal information of the converter; then, according to an embedded voltage control strategy library and a voltage stability threshold condition, an initial voltage regulation and control instruction sequence is generated in combination with voltage disturbance modal information of the converter; performing voltage change trend prediction on the voltage disturbance modal information of the converter to obtain predicted voltage disturbance modal information; performing voltage control compensation optimization on the initial voltage regulation and control instruction sequence based on the predicted voltage disturbance modal information to generate an optimized voltage regulation and control instruction sequence; and performing adaptive voltage regulation on the new energy automobile converter according to the optimized voltage regulation instruction sequence.

The invention relates to the technical field of voltage control, and discloses an ESC voltage regulator voltage control method and system based on fuzzy adaptive PID, and the method comprises the steps: collecting the output voltage of an ESC voltage regulator and a preset target voltage in real time, calculating a voltage error and an error change rate after filtering, and carrying out the calculation of the error change rate; dividing fast tracking, precise adjustment and anti-interference stability maintenance stages according to errors and change rates and generating control signals, calling corresponding fuzzy rule subsets to deduce proportional, integral and differential gain adjustment amounts, generating real-time gains in combination with initial PID parameters, calculating control amounts by using position type PID based on the real-time gains, converting the control amounts into signals to drive power switch tubes, and controlling the power switch tubes. And closed-loop adjustment is formed. According to the method, the problem that a traditional control method is poor in performance under multiple working conditions is solved, cooperative control over rapid tracking, precise adjustment and anti-interference stability maintenance of the output voltage of the ESC voltage regulator is achieved, it is ensured that the ESC voltage regulator can output stable voltage under the working conditions of starting, steady-state operation and load sudden change, and the requirement for high voltage control precision and dynamic response is met.

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.

The invention discloses an industrial park virtual power plant reactive voltage control method of multi-target multi-agent deep reinforcement learning considering energy storage life, and belongs to the technical field of virtual power plant reactive voltage control methods based on industrial data acquisition. The problem that in the prior art, a traditional industrial park virtual power plant reactive voltage control method is difficult to consider park network loss optimization and energy storage life protection at the same time is solved. According to the method, a multi-objective optimization model including network loss minimization, node voltage deviation minimization and energy storage battery service life maximization is constructed, a virtual power plant is divided through a distributed multi-agent framework, each agent trains multiple strategies in parallel through a multi-objective multi-agent deep reinforcement learning algorithm based on local observation, the Pareto front is approached, and the energy storage battery service life is maximized. High-efficiency control is realized, and each intelligent agent independently generates an energy storage reactive power regulation and active power charging and discharging instruction. The reliability of the energy storage equipment is improved, and the method can be applied to an industrial park active power distribution network scene with high renewable energy source permeation.

The invention discloses a short-circuit current limiting and short-circuit recovery transient voltage control device and method for an aviation three-stage power generation system, and the device comprises a three-stage power generator, a power generator controller, a current sensor, a voltage and current collection module, and an asymmetric half-bridge excitation control circuit. Collecting the output current iL and voltage UL of the generator through a digital processor of the generator controller; when short circuit occurs, the given voltage USet of the voltage regulating loop is linearly reduced in a piecewise mode according to the relation between the iL and a preset threshold value, so that the generator works in a constant power interval; and when the short circuit is recovered, closing the upper / lower power tubes of the asymmetric half-bridge excitation control circuit according to the relationship between UL and a preset threshold value in a grading manner, and triggering a negative-pressure follow-current mode of a main excitation winding of the generator controller to quickly extinguish the field. The method can adapt to different generators without adjusting hardware circuit parameters, has no motor ablation risk during short circuit, has transient voltage less than 350V after short circuit recovery, has no power supply interruption in the whole process, has response delay less than 1ms, and greatly improves the safety and robustness of an aviation power supply and distribution system.

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

The invention provides a wide-voltage intelligent control large-current contactor. Comprising a wide voltage control module which is composed of a rectifier bridge, a voltage acquisition module, a single-chip microcomputer control system and a DCDC conversion module and is used for converting input AC / DC voltage into stable 24VDC output; the wide-current control module is used for controlling the coil to start, the contactor can be in a working state even if power failure occurs, the stability of a power grid is ensured, and the device can be applied to the fields of uninterruptible power supply control cabinets, photovoltaic energy storage, power grid distribution and the like.

The invention relates to the technical field of power electronics, in particular to a network construction type STATCOM topological structure with a super-capacitor and a control method thereof, the topological structure is a star-shaped chain network construction type STATCOM system with a super-capacitor module power unit, the power unit comprises a super-capacitor module and an H-bridge module, and the super-capacitor module is connected with the H-bridge module in parallel; the super-capacitance module is formed by cascading three sub-modules, and each sub-module comprises a super-capacitor, a filter inductor and a DCDC circuit; the control method comprises the steps of voltage feed-forward unit phasor calculation, reactive voltage control and virtual internal potential angle calculation, virtual impedance amplitude limiting logic, bridge arm current reference instruction calculation and modulation wave instruction calculation. According to the invention, the applicability of the super capacitor module is enhanced, the design cost is saved, mutual interference between the frequency modulation characteristic and the inertia damping characteristic is avoided, the active power steady state control precision is improved, and the product safety is improved.

The invention provides a pressure-controlled high-speed fluid precise trapping device, and belongs to the technical field of chemical engineering, the pressure-controlled high-speed fluid precise trapping device comprises a high-speed fluid trap, a precise pressure-controlled unit module, a multi-stage sampling connection assembly and a positioning bracket, and the device provided by the invention realizes multi-stage series linkage control through a connecting assembly; according to the device, continuous collection of high-speed fluid in the same event and process products in different stages can be achieved, meanwhile, trapping at any position and any angle can be achieved through the positioning support, a new experimental method and means are provided for revealing of high-speed fluid carrier changes and explosion process laws, and the device adopts modular design and is easy to popularize and use. All the connectors adopt the same standard, rapid connection is achieved through threads, pins and the like, assembling and disassembling are convenient, valves and pipelines are unified in standard, the universality of parts is good, and the device is convenient to clean in the later period and good in repeatability.

The invention discloses an off-grid new energy hydrogen production start control method, system, device and medium, and relates to the technical field of new energy hydrogen production control and micro-grid operation management, and the method comprises the steps: employing energy storage zero-to-boost control and anti-interference communication to establish a bus voltage based on an off-grid system architecture; the output power of the wind turbine generator is adjusted through a variable pitch power following strategy based on short-term wind speed prediction, the power distribution proportion of the wind turbine generator and the energy storage device is dynamically adjusted by adopting an improved NSGA-II multi-target optimization algorithm in combination with the equipment health state factor, and the power output path and the response rate of the equipment are optimized; electrolytic hydrogen production is carried out by adopting electrolytic tank pre-starting condition inspection, stepped power rising and stepped starting of grid-connected transition in cooperation with closed-loop temperature flow regulation and a PID pressure management strategy, and black-start rollback and self-healing control are executed. According to the method, the stable construction of the bus voltage is realized through the boost control from zero energy storage, and the current impact in the starting process is effectively inhibited.

The invention discloses a Yellow River water conservancy project real-time monitoring system based on edge computing, and particularly relates to the technical field of cloud computing. The system constructs a flow state characteristic interval by collecting water and sediment data; loading an algorithm component based on flow state characteristics, and changing a master control pointer by using atomization operation to realize calculation power logic hot switching; analyzing a difference value between the instantaneous torque of the motor and the no-load reference to obtain a sediment deposition resistance torque; mapping the resistance moment to a digital shadow table to extract a gain compensation parameter; and resetting controller parameters and modulating the pulse width signal according to the compensation coefficient, and outputting a driving voltage to control the gate. Through the edge end algorithm hot switching technology, the problems that a traditional system is difficult to adapt to the variable water and sediment working conditions of the Yellow River and logic updating shutdown are solved, and monitoring continuity is guaranteed. The defect of power mismatching of a single driving mode is overcome, motor overload and mechanical jamming are prevented, gate control accuracy and operation stability are greatly improved, and the service life of equipment is greatly prolonged.

The invention discloses a high-voltage SVG adaptive voltage control method based on deep learning, and belongs to the technical field of power equipment, and the method comprises the following steps: S1, multi-source data collection and preprocessing: the S1, multi-source data collection and preprocessing comprises a data collection module and a data preprocessing module, the data acquisition module comprises a high-precision sensor network and acquires various data in real time; the data preprocessing module comprises missing value filling through a sliding window method, wavelet transform denoising, multi-dimensional feature proof construction and normalization processing; s2, constructing a deep learning model, wherein the construction of the deep learning model in S2 comprises a model framework module, a network parameter module and a training strategy module. According to the method, the nonlinear characteristics of the power grid are captured through the deep learning model, the method can adapt to dynamic scenes such as power grid topological structure sudden change and new energy output intermittence in real time, and in the power grid with the new energy permeability exceeding 30%, the voltage regulation error can be reduced to + / -0.5% and is remarkably superior to + / -2% of a traditional method.

The invention discloses a self-adaptive coordination dynamic voltage control method and system based on a micro-grid, and relates to the field of micro-grid self-adaptive coordination dynamic voltage control. In order to solve the defects that an existing micro-grid model cannot adapt to complex disturbance and dynamic load and cannot accurately reflect the actual network state when regulating and controlling the dynamic voltage of the micro-grid, the current operation mode of the micro-grid is analyzed; when the synchronization error is smaller than the tolerance, the PCC is closed and switched to a grid-connected operation mode; if the current large power grid is normal, the grid-connected operation mode is maintained; if the current large power grid is abnormal, starting island detection and judging that the current microgrid is in an off-grid operation mode; executing a corresponding grid-connected control strategy, an off-grid control strategy or a switching pre-control strategy according to the voltage value; and when the execution of the current control strategy is detected to be abnormal, automatically terminating the execution of the current control strategy, rolling back to the previous safe state, and starting a standby plan at the same time. The method is mainly used for carrying out adaptive coordination dynamic control on the output voltage of the micro-grid.

The invention discloses a whole vehicle power hardware-in-the-loop simulation test system and method under a P2.5 + P4 hybrid architecture. The whole vehicle power hardware-in-the-loop simulation test system comprises a controller, a test cabinet and an upper computer system, the hybrid power gearbox control system is electrically connected with the high-voltage control system; the test cabinet is electrically connected with the hybrid power gearbox control system, the high-voltage control system and the upper computer system; the upper computer system comprises a management module, a signal interface module, a controller interface module and a virtual simulation vehicle module, the management module is connected with the test cabinet and the signal interface module, and the signal interface module is used for realizing signal interaction between the controller interface module and the management module; the controller interface module is connected with the signal interface module, the Soft ECU module and the power simulation module. Standardized development of the power simulation test system is realized, the modular design supports rapid adaptation of different vehicle type platforms and power architectures, and repeated development is reduced.

The utility model provides a gain control device of a silicon photomultiplier, which comprises a temperature sensing module arranged on the surface of the silicon photomultiplier and used for sensing the temperature of the silicon photomultiplier and generating temperature information; one end of the voltage conversion circuit is connected with the first power supply, the other end is connected with the power supply input end of the silicon photomultiplier, and the voltage conversion circuit is used for performing voltage conversion on the first power supply and outputting conversion voltage to the silicon photomultiplier; the processing module is connected with the temperature sensing module and the voltage conversion circuit and used for obtaining the temperature information, generating a voltage control signal based on the temperature information and according to the temperature-voltage mapping relation, sending the voltage control signal to the voltage conversion circuit so as to supply power to the voltage conversion circuit, conducting voltage conversion on the first power source based on the voltage control signal and outputting the converted voltage. And outputting a conversion voltage corresponding to the voltage control signal. The gain control device of the silicon photomultiplier provided by the utility model improves the accuracy of gain control of the silicon photomultiplier.

The invention discloses a distributed photovoltaic group scheduling and group control method, which belongs to the technical field of distributed photovoltaic, and comprises the steps of data acquisition monitoring, intelligent scheduling algorithm, power prediction optimization, cluster division, cluster autonomous optimization control and inter-cluster distributed coordination control. The cluster autonomous optimization control and the inter-cluster distributed coordination control form a double-layer voltage control mode, the cooperation of the two can significantly improve the voltage stability of the power distribution network and reduce the active power loss of the line, after multiple iterations, the node voltage of the whole network is stabilized in an allowable range, the voltage fluctuation is significantly reduced, the consumption capability of distributed photovoltaic is improved, and the system performance is improved. And an effective technical support is provided for safe and stable operation of the power distribution network under high-permeability distributed photovoltaic access.

The invention belongs to the technical field of community power distribution network dispatching, and particularly relates to a community power distribution network and emergency energy storage vehicle joint distributed optimization method, which comprises the following steps of S1, dividing an original topological structure of a community power distribution network into a plurality of mutually independent sub-regions by adopting a robust self-adaptive partitioning algorithm; s2, for each sub-region, constructing a corresponding reactive power optimization model by taking minimization of network loss, voltage deviation and emergency energy storage vehicle operation cost as targets; s3, adopting an improved ADMM algorithm to carry out joint scheduling optimization solution; the improvement comprises setting the penalty parameter as a penalty parameter which is dynamically adjusted according to a preset rule and a residual error; and S4, scheduling the community power grid system and the emergency energy storage vehicle by using the joint optimization scheme obtained in the step S3. According to the method, on the premise that the voltage stability of the community power distribution network is guaranteed, efficient scheduling of the emergency energy storage vehicles is achieved, and joint optimization of voltage control of the community power distribution network and scheduling of the emergency energy storage vehicles is achieved.

The invention provides a level shifter and a memory device including the same. The level shifter includes: a medium voltage output circuit configured to output a medium voltage based on an input voltage stepped between a first voltage level and a second voltage level; a feedback circuit configured to output a feedback voltage and an output voltage stepped between a positive target voltage level and a negative target voltage level based on the positive target voltage, the negative target voltage, and the medium voltage; a pull-up voltage control circuit configured to output the first voltage or the positive target voltage to the medium voltage output circuit based on the feedback voltage; and a pull-down voltage control circuit configured to output the second voltage or the negative target voltage to the medium voltage output circuit based on the feedback voltage.

The invention discloses a voltage regulation control method and system for an electric power regulator, and belongs to the technical field of voltage regulation, and the method specifically comprises the steps: collecting parameters of a power grid side and a load side, including current and voltage, building an operation model of the electric power regulator based on parameter identification, and according to the operation model and a target output voltage, calculating the voltage of the electric power regulator. The method comprises the following steps: calculating to obtain a reference voltage sequence in combination with electric energy quality and efficiency constraints, monitoring the states of a power grid and a load in real time, projecting the reference voltage sequence to a safe operation envelope when voltage fluctuation or abnormity is detected, performing hierarchical derating control, generating a regulation signal of the power regulator based on the corrected reference voltage sequence, and outputting the regulation signal of the power regulator. The operation model of the power regulator is calibrated through real-time feedback; the power quality and efficiency can be considered under the normal working condition, stable voltage control can be kept during power grid fluctuation, frequency deviation or load sudden change, and resource waste caused by single shutdown or extensive derating is avoided.

The invention discloses a voltage control method and system considering cooperation of multiple types of reactive compensation equipment, and the method comprises the steps: inputting different types of reactive compensation equipment according to the voltage fluctuation type of a power grid; wherein the power grid voltage fluctuation type comprises steady-state voltage fluctuation and transient-state voltage fluctuation; wherein when the steady-state voltage fluctuates, the discrete reactive power compensation device is firstly put into use, and if the voltage of the power grid is still unstable, the continuous reactive power compensation device is put into use; wherein when the transient voltage fluctuates, the continuous reactive power compensation device is put into use. When the voltage drops, the reactive power demand of the power grid can be quickly responded, the cooperation among the reactive power compensation devices is optimized, the overall efficiency of reactive power compensation and the stability of the power grid are improved, the suppression capability on overvoltage when the voltage transiently changes is remarkably enhanced, and an important technical guarantee is provided for safe and reliable operation of a power system.

A semiconductor memory device includes: a memory cell array including a plurality of NAND strings, each of the plurality of NAND strings including a plurality of memory cell transistors connected to each other in series; a plurality of word lines commonly connected to the plurality of memory strings and connected to the plurality of memory cell transistors, respectively; and a row decoder configured to supply a predetermined voltage higher than a ground voltage to each of the plurality of word lines after a program operation for writing data to a selected word line is completed.

The invention relates to the technical field of articles for old people, in particular to an adjusting method, system, equipment and medium for improving the short circuit ratio of a new energy station, and the method comprises the steps: calculating a first target index and a second target index of the new energy station, and switching a part of grid-connected converters into a virtual synchronous generator control mode; when the second target index does not meet the short-circuit ratio control requirement, changing the equivalent impedance of the grid-connected point by adjusting the virtual impedance of the virtual synchronous generator so as to reduce the second target index of the new energy station; and when the grid fault causes the voltage drop of the grid-connected point, reactive voltage control is carried out through the virtual exciter of the virtual synchronous generator, and voltage support is provided for the grid-connected point. The method has the beneficial effects that flexible and efficient dynamic adjustment is realized by using the virtual synchronous generator, the system operation efficiency is improved, and the short-circuit ratio of a new energy field station is improved by combining virtual impedance and a reactive power support function, so that the operation capability of the new energy field station in a weak power grid is enhanced.