Product
Patsnap Eureka
For R&D, Patsnap Eureka makes reading and utilizing patents & technical documents easy.
Patsnap Eureka AIR
Designed for self-driven R&D workflows. Generate viable solutions, solve complex R&D challenges, empower your innovation with AI.
Patsnap Eureka Materials
Designed for material experts only. Revolutionize your material R&D, from search, analyze, to developing new materials.
Feature
TechResearch
Generate reliable direction feasibility study reports for your R&D in just a few steps.
TechSeek
Discover and master advanced knowledge NOW. Basics, ideas, possibilities, all at once.
TechMind
As an expert in R&D Theories, TechMind can generates customized viable solutions instantly.
TechRisk
Analyze your overall solution with one click, know your potential R&D risks in advance.
TechMonitor
Get weekly tech updates, stay abreast of the latest tech innovations and key insights.
Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
132 results about "Active power flow" patented technology
Efficacy Topic
Property
Owner
Technical Advancement
Application Domain
Technology Topic
Technology Field Word
Patent Country/Region
Patent Type
Patent Status
Application Year
Inventor
Symmetry method for obtaining mlutiterminal direct current power network nonlinear active power flow
The invention relates to a symmetry method for obtaining multitermianl direct current power network nonlinear active power flow. First a symmetric nonlinear indeterminate equation system (S1) of node injected active power with respect to node voltage offset is buit, then a symmetric linear linear indeterminate equation system (S2) of a node injected active power increment with respect to a node voltage offset increment is built according to the symmetric nonlinear indeterminate equation system, node voltage offset of each node and the total quantity of node voltage (S3) in the multiterminal durect current power network are obtained according to the symmetric linear indeterminate equation system and known node injected active power, and finally nonlinear active power flow (S4) of each branch in the multiterminal durect current power network is obtained according to the node voltage offset of each node in the multierminal direct current power network, whrein the node voltage offset of all nodes in the multiterminal direct current power network is equally treated, the obtained all node voltage offset always draws close to zero, a reference node does not need to be selected, and obtained nonlinear active power flow is uniqud and reasonable.
Owner:SHENZHEN UNIV
Active power flow optimizing distribution method for alternating-direct current parallel system containing soft direct current power transmission
ActiveCN103368173ADc network circuit arrangementsAc network circuit arrangementsEngineeringOperation mode
The invention discloses an active power flow optimizing distribution method for an alternating-direct current parallel system containing soft direct current power transmission, and solves the reasonable distribution problem of the active power flow of the alternating-direct current system under the alternating-direct current parallel operation mode of the soft direct current power transmission. The method comprises the steps of obtaining basic parameters of a power grid to be analyzed; establishing corresponding target functions by taking factors such as alternating-direct current equipment loss, avoiding parallel loop current, the safety and stabilization of the power grid, the utilization rate of the alternating-direct current equipment and fault rate as target conditions according to the obtained basic parameters of the power grid; establishing multiple target optimization functions according to all established target functions; designing a subjection function for each target function according to the fuzzy theory; and resolving the optimal solution of the multiple target functions by adopting a fuzzy algorithm. The method considers the constrain of multiple target conditions, obtains the optimal active power control reference value under the alternating-direct current parallel operation of the soft direct current power transmission system by resolving the multi-target optimal function, and is more reasonable in comparison with the method relying on experience to set the active power reference value.
Owner:ELECTRIC POWER RESEARCH INSTITUTE, CHINA SOUTHERN POWER GRID CO LTD +1
Acquisition method for minimum phase linear effective power flow of alternating current power grid
InactiveCN104995811AAccurately reflect the essential characteristicsSpecial data processing applicationsAc network circuit arrangementsEffective powerPower grid
The invention is in the field of electrical engineering, and relates to an acquisition method for minimum phase linear effective power flow of alternating current power grid. The method includes establishing a symmetric linear function relationship between an active power injected at a node and a node voltage phase according to the known parameters of alternating current power grid, the operating characteristics of alternating current power grid, and the active power injected at the node; establishing a linear function relationship between the node voltage phase and the minimum phase of the active power injected at the node according to the symmetric linear function relationship; acquiring the minimum voltage phase at each node in alternating current power grid; establishing a linear function relationship between the linear active power flow at the minimum phase of a branch and the active power injected at the node according to the linear function relationship of the minimum phase, the known nonlinear active power flow of the branch, the active power injected at the node, and the operating characteristics of alternating current power grid; and acquiring the minimum phase linear active power flow of each branch. The acquisition results are unique, follow the circuit regularity, and accurately reflect the essential characteristics of phase states' variation of alternating current power grid.
Owner:SHENZHEN UNIV
Power system cascading failure simulation method based on unified power flow controller
ActiveCN103311926AIn line with actual operating conditionsPracticalSpecial data processing applicationsAc network circuit arrangementsCascading failureSimulation
The invention provides a power system cascading failure simulation method based on a unified power flow controller and belongs to the technical field of power system security and reliability protection. A computer is used for determining the installation position of the unified power flow controller in a power system firstly, determining an active power flow betweenness threshold value of each node of the power system, performing power system cascading failure simulation based on the unified power flow controller and finally calculating measurement index for reflecting severity of cascading failure through procedures. The power system cascading failure simulation method gives consideration to power flow directivity and the operation mode of the system, optimizes the installation position for installing the unified power flow controller, effectively performs line parameter regulation while meeting safe operation constraints of the power system, and can reflect the propagation process of the cascading failure of the power system actually. The power system cascading failure simulation method based on the unified power flow controller can be widely applied to the cascading failure simulation of the power system, is particularly suitable for the cascading failure simulation of a large-scale complicated power system, and provides a scientific basis for preventing occurrence of the cascading failure of the power system.
Owner:CHONGQING UNIV
Coordination control method
InactiveCN102157936AEasy to controlImprove the level of control technologySingle network parallel feeding arrangementsAc network voltage adjustmentAutomatic controlAutomatic train control
The invention discloses a coordination control method and relates to the technical field of control of power systems. The coordination control method comprises the following steps: S1. measuring real-time voltage, current, active power and reactive power of all bus bar nodes, and setting an AGC (automatic gain control) command; S2. performing voltage check according to the AGC command, and outputting voltage predicted value and check result of the selected bus bar node; S3. outputting the AGC command if the AGC command meets the voltage requirement, otherwise, implementing the step S4; S4. performing AVC (automatic voltage control) according to the voltage predicted value of the selected bus bar node, and calculating voltage adjusting value of the selected bus bar node after performing the AVC; S5. performing power check according to the voltage adjusting value of the selected bus bar node, and outputting power predicted value and the check result of a call wire; and S6. outputting anAVC command if the AVC command meets the power requirement, otherwise, resetting the AGC command, and returning to implement the step S2. By adopting the method, active power flow and reactive power flow of the power system can be well controlled, and economy and safety of operation of the power system can be improved.
Owner:TSINGHUA UNIV +1
Two-stage initiative separation method based on normalized spectral clustering and constrained spectral clustering
ActiveCN102244394AImprove solution qualityFast solutionSingle network parallel feeding arrangementsDynamoActive power flow
The invention discloses a two-stage initiative separation method based on normalized spectral clustering and constrained spectral clustering. The method comprises the steps of: in the first stage, recognizing coherent generator groups by using normalized spectral clustering and forming pairwise constraints by using the coherent generator groups; and in the second stage, finding separation sections satisfying the pairwise constraints and with the minimum active power flow shock by using constrained spectral clustering. When a system needs to be separated into a plurality of islands, a recursive bisection method can be adopted. The algorithm provided by the invention takes two factors, i.e., generator coherency and the minimum active power flow shock, into account, and the initiative separation problem can be calculated in real time without simplifying system topology.
Owner:SHANDONG UNIV
Flexible looped network control system operation and power flow optimization method
ActiveCN104269847AIncrease flexibilityImprove securityElectric power transfer ac networkControl systemSimulation
The invention discloses a flexible looped network control system operation and power flow optimization method, and belongs to the field of electric power system operation and power flow optimization. The method solves the problem of reasonable system active power flow allocation problem under the normal and fault conditions of the flexible looped network control system. The method includes the steps that network parameters of a target power grid are obtained in real time based on a D5000 system; according to the obtained power grid basic parameters, the element load rate and the system power supply capacity serve as target conditions, and corresponding target functions are built; a multi-target optimization function is determined based on all the target functions; according to a fuzzy theory, subordinating degree functions of all the target functions are made, and the optical solution of the multi-target optimization function is obtained through a fuzzy algorithm. According to the method, the multiple target functions serve as constraint conditions, the optimal power flow allocation under the normal and fault operation conditions of the flexible looped network control system is obtained, and the reliability and economy of power grid operation are improved.
Owner:STATE GRID CORP OF CHINA +1
Method and apparatus for increased energy harvest in a microgrid
A method and apparatus for power converter current control. In one embodiment, the method comprises controlling an instantaneous current generated by a power converter that is part of an AC battery such that (i) the power converter appears, from the perspective of an AC line coupled to the power converter, as a virtual AC voltage source in series with a virtual impedance, wherein real and reactive phasor currents for the power converter are indirectly controlled by modifying amplitude and phase of a virtual AC voltage waveform that defines the virtual AC voltage source, and (ii) active power flow is prioritized while the AC battery is operating in a charge mode.
Owner:ENPHASE ENERGY
Subsynchronous oscillation method and apparatus for static synchronous series compensator suppression system
ActiveCN106877363AQuick pickIncreased level of stabilityFlexible AC transmissionReactive power adjustment/elimination/compensationSystem of imprimitivityPower grid
The invention relates to a subsynchronous oscillation method and apparatus for a static synchronous series compensator suppression system. The subsynchronous oscillation method comprises the steps of taking an included angle between an SSSC (static synchronous series compensator) output voltage and an alternating current circuit current, and modulation ratio of the SSSC as generator influencing parameters by the SSSC according to a system linear model of an SSSC-containing single-machine infinite-bus system; taking voltage frequency deviation and active power flow of an SSSC apparatus mounting point as SSSC modulation ratio influencing parameters; taking the voltage frequency deviation and active power flow of the SSSC apparatus mounting point as input to establish a transfer function of a damping controller, wherein the voltage frequency deviation and the active power flow of the SSSC apparatus mounting point are taken as input of the damping controller; and optimizing control parameters of the transfer function of the damping controller. By adoption of the technical scheme provided by the invention, the power grid operating damping and stability can be improved; meanwhile, the damping characteristic of the power grid in a region where the static synchronous series compensator is located is optimal; and the subsynchronous oscillation method is also applicable to design of an actual controller.
Owner:GLOBAL ENERGY INTERCONNECTION RES INST CO LTD +2
Generator set active power real-time dispatching method considering wind power prediction error
ActiveCN104810863AGuaranteed Security ConstraintsAccurately obtainedSingle network parallel feeding arrangementsWind energy generationElectricitySimulation
The invention discloses an electric system active power real-time dispatching method considering wind power prediction error. The electric system active power real-time dispatching method comprises the following steps of describing random distribution character of the wind power prediction error by using Laplace distribution; by taking economic efficiency optimum and wind curtailment minimum as two targets, introducing a chance constraint condition; solving active power flow probability distribution of a system on the basis of a probabilistic power flow method for Latin hypercube sampling; establishing a buffer generator set active power optimum allocation model considering the wind power prediction error, and solving a chance constraint planning model by adopting an improved genetic algorithm. According to the electric system active power real-time dispatching method disclosed by the invention, the wind power prediction error is considered during real-time dispatching, power unbalance and flow off-limit brought to the system by wind power output offset can be avoided, and the safe operation of the system is guaranteed; moreover, while the wind power prediction error is assimilated, the wind power accepting ability is increased by the system.
Owner:SOUTHEAST UNIV
Power grid node importance degree determination method
InactiveCN105389670AThe evaluation result is reasonableResourcesInformation technology support systemDirected graphHITS algorithm
Owner:ZHEJIANG UNIV
Power grid component cascading failure simulation method
InactiveCN107069705ASimulation close to realityTaking into account the accuracyAc network circuit arrangementsCascading failureFailure rate
The invention discloses a power grid component cascading failure simulation method. According to the invention, voltage and line active power flow, which have great influences for the failure rate of a component, are selected to act as variables to correct the failure rate of the component so as to enable the simulation to be closer to the reality; traditional methods such as proportional load shedding, nearby load shedding and load shedding performed according to the importance degree of loads are abandoned when load shedding is performed, an optimal load shedding method is adopted, and all factors, which can be used for adjustment, in the system are comprehensively utilized, so that a problem of load shedding is well solved theoretically so as to acquire an operation scheme capable of enabling the overall benefit of the system to be the highest; and the power grid component cascading failure simulation method not only considers an alternating-current mode, but also considers a direct-current mode in power flow calculation, so that both the calculation accuracy and the calculation speed are well considered.
Owner:ELECTRIC POWER RES INST OF GUANGXI POWER GRID CO LTD
An electrified railway in-phase power supply and transformation system
PendingCN109217330ADoes not generate through powerSimple structureFlexible AC transmissionReactive power adjustment/elimination/compensationEngineeringHigh pressure
The invention discloses an electrified railway in-phase power supply and transformation system, which relates to the technical field of AC electrified railway power supply. The in-phase power supply and transformation system comprises n traction substations, a single-phase high-voltage transmission line and a traction network, wherein, the first traction substation comprises a three-phase high-voltage bus bar, a first main transformer connected with the three-phase high-voltage bus bar and a negative sequence compensation device connected with the three-phase high-voltage bus bar; The second traction substation to the nth traction substation are respectively connected with the single-phase high-voltage transmission line and the traction network. The negative sequence compensation device isinstalled in the first traction substation, and comprises a three-phase compensation transformer, a three-phase reactive power compensation device and a measurement and control unit. The negative sequence compensation device generates the negative sequence power flow through the three-phase reactive power compensation device, and does not change the active power flow of the whole system; At the same time, the power supply mileage of electrified railway without phase separation is greatly prolonged by using the advantages of large transmission power and long transmission distance of high voltage transmission line.
Owner:SOUTHWEST JIAOTONG UNIV
Method for realizing ice melting in distribution network by making active ring current with flexible multi-state switches
ActiveCN109494615AAccurately control powerQuick responseOverhead installationApparatus for overhead lines/cablesPhase differenceRing current
The invention discloses a method for realizing ice melting in a distribution network by making an active ring current with flexible multi-state switches. The method comprises: selecting an ice-meltingtarget line; reconstructing a distribution network through a distribution network communication switch and reconstructing the ice-melting target line into an ice-melting ring network path; setting working modes of flexible multi-state switches; to be specific, setting a flexible multi-state switch at the ice-melting target line side to work in a PQ mode and a flexible multi-state switch at a non-ice-melting communication line side to work in a direct-current constant-voltage control mode; and calculating an active power P of the ice-melting line based on an ice-melting current needed by the ice-melting target line, using the P as an active power reference value of the flexible multi-state switch at the side, starting the flexible multi-state switches at the two sides, and adjusting voltage phases of the flexible multi-state switches, and generating an active power flow in positive correlation with a phase difference value. Therefore, problems of complicated line outage operation and the short-circuiting procedures melting efficiency and the limited length of the ice-melting line during the ice melting of the transmission line in the prior art can be solved.
Owner:GUIZHOU POWER GRID CO LTD
Security constrained optimal power flow method based on power flow transfer relation
InactiveCN108075476ASmall scaleReduce computing scaleAc networks with different sources same frequencyTransformerFault analysis
The invention discloses a security constrained optimal power flow method based on power flow transfer relation. The method is characterized by establishing active power flow transfer relationship before and after fault based on anticipated fault analysis; describing fault-state branch active power flow into a ground-state branch active power flow function, so that the fault-state branch active power flow constraint is described as ground-state branch active power flow linear inequality constraint; and carrying out grouping on parallel circuits and parallel main transformers, and reducing the scale of monitored branches by utilizing power flow distribution relationship of branches in each group, and carrying out filtering on the fault-state branch active power flow constraint by utilizing the characteristic that short-time flow capacity of a device is obviously larger than long-term flow capacity thereof to minimize the calculation scale of the SCOPF problem as far as possible. The method has a good effect.
Owner:STATE GRID FUJIAN ELECTRIC POWER CO LTD +1
DC power flow calculation method considering charging capacitance
ActiveCN106385035AImprove calculation accuracyAc networks with different sources same frequencyCapacitanceVoltage amplitude
The invention relates to a DC power flow calculation method considering charging capacitance. The DC power flow calculation method comprises steps of (1) calculating a trigonometric function simplification method and an approximation coefficient, (2) constructing a DC power flow model considering a charging capacitance, (3) incorporating a circuit model containing a charging capacitor and a grounding admittance, (4) using a complete admittance matrix parameter to calculate a coefficient matrix, (5) solving voltage amplitudes of all PQ nodes through back substitution of a correction phase angle to obtain voltage amplitudes and phase angles of all nodes in a network and using complex power flow equation to calculate line circuit complex power. Compared with a DC power flow algorithm without considering a charging capacitance, the DC power flow calculation method improves calculation accuracy of the voltage amplitude and the reactive power flow on the premise that the active power flow calculation accuracy of the current DC power flow algorithm is maintained, and enables the power flow algorithm to be adapted to calculation of reactive power flow of a power transmission system.
Owner:国网江西省电力有限公司经济技术研究院 +1
Adaptive precise harmonic compensation method and device based on photovoltaic grid-connected system
InactiveCN108736479AReduce compensation costsReduce Harmonic Distortion RateSingle network parallel feeding arrangementsPhotovoltaic energy generationClosed loopEngineering
The invention discloses an adaptive precise harmonic compensation method based on a photovoltaic grid-connected system. The method comprises the following steps: detecting output current and an outputvoltage on an AC side of a photovoltaic grid-connected inverter when the photovoltaic grid-connected inverter works at a maximum power tracking point; detecting the remaining capacity of the photovoltaic grid-connected inverter, judging the active power flow directions of different subharmonics, and formulating a compensation strategy; adaptively outputting a to-be-compensated component switch on-off signal according to the remaining capacity of the photovoltaic grid-connected inverter; and achieving precise harmonic compensation by using a repeated double closed-loop controller according tothe switch on-off signal. According to the adaptive precise harmonic compensation method disclosed by the invention, the remaining capacity of the inverter is dynamically tracked according to the external illumination changes, the compensation cost of the photovoltaic inverter can be effectively reduced, and the distortion rate of the grid side harmonics is maximally reduced while making full useof the limited remaining capacity of the photovoltaic grid-connected inverter.
Owner:CENT SOUTH UNIV
Unified power flow controller (UPFC)-based overload control method of power transmission line
ActiveCN106953320AAutomatically solve overload problemsPrevent overloadAc network circuit arrangementsOverload controlPower grid
The invention discloses a unified power flow controller (UPFC)-based overload control method of a power transmission line. The UPFC-based overload control method comprises the steps of firstly, determining a bus set which is monitored and protected by calculating sensitivity of current amplitude of each power transmission line in a power grid on change of an active power flow set value of a UPFC; and secondly, monitoring the current amplitude of the power transmission line in the set during the running process of the power grid, wherein the active power flow set value of the UPFC can be automatically adjusted by a control strategy so that a load of the power transmission line is controlled to be within a safe and stable running range when overload of the power transmission line is monitored. By the circuit overload control strategy, the problem of overload of the power transmission line brought by a fault or load / power generation fluctuation can be automatically solved, the safe running of the power transmission line is ensured, and the overload control method is very necessary for improvement of the running flexibility of a system and the safety of a power system and has important significance to engineering application of the UPFC and safe and stable running of the power grid.
Owner:JIANGSU ELECTRIC POWER CO +2
A negative sequence compensation device and method for an electrified railway in-phase power supply and transformation system
PendingCN109066718ADoes not generate through powerSimple structureFlexible AC transmissionReactive power adjustment/elimination/compensationThree-phaseHigh pressure
The invention discloses a negative sequence compensation device and method of an electrified railway in-phase power supply and transformation system, belonging to the technical field of electrified railway power supply. The in-phase power supply substation system comprises a first traction substation, a second traction substation,... and an n-th traction substation, n >= 2; The first traction substation, the second traction substation,... and the nth traction substation are respectively connected with the single-phase high-voltage transmission line and the traction network; The negative sequence compensation device is installed in the first traction substation and comprises a three-phase compensation transformer, a three-phase reactive power compensator connected with the three-phase compensation transformer and a measurement and control unit connected with the three-phase reactive power compensator. The invention can effectively solve the technical problem that the active power flow of the traction substation group is not changed, and the negative sequence centralized compensation of the traction substation group is solved through the reactive power flow control.
Owner:SOUTHWEST JIAOTONG UNIV
Timing sequence optimization control method for distributed power flow controller, and controller
InactiveCN103368180AExcellent reactive power compensation performanceReal-time adjustment of active power flowReactive power adjustment/elimination/compensationReactive power compensationSystem of imprimitivityTotal harmonic distortion
The invention discloses a timing sequence optimization control method for a distributed power flow controller, and the controller, wherein a DPFC (deviation of power frequency component) device is connected into a single-machine infinite bus system, and the both ends of the single-machine infinite bus system are connected with a Y-Delta-type transformer; the DPFC device is used for switching current converters at the series side of the DPFC device in different time periods, and the number of the current converters switched in each time period is calculated according to a corresponding formula. According to the timing sequence optimization control method disclosed by the invention, the active power flow of an electric transmission line is adjusted in real time by controlling the switching time of the single-phase current converters at the series side of the DPFC device; simultaneously, the reduction of the active power of the electric transmission line during the charging energy storage process of direct-current capacitors at the series side of the DPFC device is prevented, the total harmonic distortion of a line current caused by the plurality of single-phase current converters is avoided, and the reactive compensation performance of the DPFC device is optimized.
Owner:WUHAN UNIV OF TECH
Method and device for wind generating set zero-transition dynamic grid connection
ActiveCN105958528AExtended service lifeReduce power lossSingle network parallel feeding arrangementsWind energy generationGrid-tie inverterNew energy
The invention discloses a method and a device for wind generating set zero-transition dynamic grid connection, and relates to the field of new energy resources. The method comprises the steps of carrying out wind generating set AC / DC converter and DC / AC converter rectification and inversion, acquiring electric physical quantity data of a power grid, a set and a grid-connected switch, detecting zero-transition dynamic grid connection conditions, carrying out grid-connected switch and wind generating set grid-connected inverter coordination control, and carrying out active power flow direction detection and zero-transmission dynamic grid connection control. The device disclosed by the invention is provided with a zero-transition dynamic grid connection signal unit, a zero-transition dynamic grid connection condition detection and active power flow direction detection unit, an electronic power switch unit and a zero-transition dynamic grid connection control unit. Compared with the prior art, the method and the device have the characteristics that a filter is energy-saving, the wind power generation efficiency is improved, the grid voltage quality is improved, and the service life of the grid-connected inverter is prolonged.
Owner:WUHAN UNIV
AC-DC power grid vulnerable line analysis method and system
The invention provides an AC-DC power grid vulnerable line analysis method. The method comprises the steps of acquiring a topological structure of an AC-DC power grid to calculate an original active power flow of each line in the AC-DC power grid, determining and simulating the active power of each line after each line is cut off, calculating an active power flow increment matrix in combination with the original active power of each line, and further acquiring an AC power flow transfer correlation matrix in combination with the safety margin of each line, calculating AC line power flow increment caused by DC locking and influence indexes of AC line on-off on a DC system, and acquiring an AC-DC power flow transfer correlation matrix in combination with the AC power flow transfer correlationmatrix, and converting the AC-DC power flow transfer correlation matrix into a line vulnerability degree vector to obtain a line with the highest vulnerability value as a power grid power failure keyline. By implementing the method, the mutual influence between the AC system and the DC system is considered, and the key line which has an important influence on the cascading failure of the power system can be identified, so that the analysis on the vulnerable line of the AC and DC power grid is realized.
Owner:SHENZHEN POWER SUPPLY BUREAU
A 360-degree quadrature direct power flow controller and a working method thereof
PendingCN109088410AReduced insulation requirementsLow costAc networks with different sources same frequencyOutput transformerEngineering
A 360-degree quadrature direct power flow controller and a working method thereof are disclosed. That direct power flow controller comprises a three-phase input transformer module, an input selector switch, a single-phase Buck alternating current unit circuit module, a three-phase filter, an output selector switch and a three-phase output transformer module. The input end of the direct power flowcontroller is connected in parallel to the high-voltage power network, and the output end of the direct power flow controller is connected in series to the high-voltage power network. The input selector switch is connected to the primary side or the secondary side of the three-phase input transformer module, and the output selector switch is connected to the primary side or the secondary side of the three-phase output transformer module. The single-phase Buck alternating current unit circuit module comprises an A-phase Buck AC unit circuit, a B-phase Buck AC unit circuit and a C-phase Buck ACunit circuit with the same circuit structure. The controller only comprises a simple Buck alternating current unit circuit, and can control the voltage phase and amplitude of the transmission terminalof the power network at the same time through only one-stage power conversion, can respectively control the active power flow and the reactive power flow in the line, and realizes the adjustment of the phase angle of the output voltage by 360 DEG.
Owner:SUZHOU UNIV
Energy storage configuration method, system and device, and readable storage medium
ActiveCN110247397ATrend crossing does not happenGood receptivitySingle network parallel feeding arrangementsAc network load balancingNew energyPower grid
The invention discloses an energy storage configuration method, system and device, and a readable storage medium. The method comprises the steps of obtaining system parameters and historical operation data of each node, each branch and each generator set in a target power grid; determining intraday maximum operation data corresponding to each item of historical operation data under different guarantee rates; according to the intraday maximum operation data and the system parameters, calculating an intraday active power flow of each branch under different guarantee rates, and determining a corresponding intraday power flow out-of-limit curve; determining a track sensitivity curve and a corresponding absolute value mean value according to the intraday power flow out-of-limit curve of each branch under different assurance rates; selecting a branch corresponding to the absolute value mean value in the target range as a dominated branch, and determining an energy storage node on a to-be-configured branch; and calculating the energy storage power and the maximum charge-discharge electric quantity of the energy storage node so that the corresponding to-be-configured branch does not generate power flow out-of-limit at a preset guarantee rate. According to the invention, power grid operation is ensured, and excellent new energy acceptance capability and high economical efficiency are provided at the same time.
Owner:GUANGDONG POWER GRID CO LTD +1
Calculation method of active power of stable section after UHVDC lockout fault
ActiveCN109256815AQuick analysisElectric power transfer ac networkSingle network parallel feeding arrangementsUltra high voltageSafety control
The invention discloses a method for calculating the active power of a stable section after an ultra-high voltage direct current blocking fault. According to the active power imbalance caused by the direct current blocking fault, the method distributes the active power imbalance amount to each generator according to a synchronous power coefficient, and calculates the active power flow of the section at the fault instant. Aiming at the unbalance of active power caused by DC blocking fault and safety control system operation, the active power of generator and load node is determined according tothe static frequency characteristic, and the section active power flow from transient state to steady state is calculated. The active power of generator and load node is determined according to the spinning reserve and climbing rate of generator in the process of recovering to the rated frequency, and the section active power flow in the process of secondary frequency modulation is calculated. The invention respectively calculates the section active power flow in the instant of fault, the transient process transitioning to the steady state and the secondary frequency modulation operation process according to the DC blocking fault, and realizes the fast analysis of the stable section active power under the large-scale active power unbalance quantity.
Owner:STATE GRID NINGXIA ELECTRIC POWER +3
Power distribution transformer power supply area interconnection-based power distribution network management and control method and system
PendingCN110739694AImprove operational efficiencyLow load distribution transformer reliefAc networks with different sources same frequencyDistribution transformerPower grid
Owner:NARI TECH CO LTD
Negative sequence compensation control device, system and method of traction substation group
ActiveCN108923440ADoes not generate through powerSimple structureFlexible AC transmissionReactive power adjustment/elimination/compensationPower compensationThree-phase
The invention provides a negative sequence compensation control device, system and method of a traction substation group. The negative sequence compensation control device comprises n current transformers and n voltage transformers of n traction substations in the traction substation group, a fiber network and a controller, wherein an input end of the controller is connected with a first current transformer and a first voltage transformer of a first traction substation and then is connected with the current transformers and the voltage transformers of other (n-1) traction substations by the fiber network, and an output end of the controller is connected with a control end of a three-phase passive power compensation device. By the negative sequence compensation control device, the equipmentproblem of concentrated compensation of dispersed negative sequences generated by each traction substrate and the technical problem of real-time compensation can be effectively solved without changing active power flow of a traction network of the traction substation group.
Owner:SOUTHWEST JIAOTONG UNIV
Multi-section online stability limit calculation method and system based on sensitivity analysis
The invention discloses a multi-section online stability limit calculation method and system based on sensitivity analysis. The method comprises the steps of acquiring power transmission section composition branch information, determining a tide direction and a corresponding power vector of each branch according to the power transmission section composition branch information, and distinguishing asending end area and a receiving end area of a power transmission section; performing network topology analysis on a power grid, and determining a receiving-end generator node set and a sending-end generator node set; calculating the comprehensive sensitivity of each node in the receiving-end generator node set and the sending-end generator node set, and screening to generate a power grid unit output adjustment strategy; calculating section active power flow according to the unit output adjustment strategy; checking whether thermal stability out-of-limit exists in the section limit power flowor not; and if not, determining a stable limit according to the section active power flow. The method and the system do not need to depend on offline calculation experience of scheduling experts, andcan effectively adapt to real-time change of a power grid operation mode.
Owner:CHINA ELECTRIC POWER RES INST +3
UPFC line side reactive power flow optimization control method
ActiveCN105914741AImprove stabilityActive power is smallFlexible AC transmissionReactive power adjustment/elimination/compensationClosed loopPower grid
The invention relates to a UPFC line side reactive power flow optimization control method. The core idea is that reactive power consumed by lines is provided by a UPFC, and the sending end and receiving end power grids do not provide reactive power. The method comprises the following steps: calculating the reactive power loss of a line according to the current effective value of the line and the power grid impedance, and taking the reactive power loss as a line reactive power flow instruction of a series side converter of a UPFC; and performing subtraction between the reactive power of a sending end power grid and zero, and carrying out closed-loop control to get a reactive power instruction of a parallel side converter. Through the method, the capability of the UPFC to control the active power flow of lines is enhanced under constant capacity of the UPFC. Moreover, as the UPFC provides reactive power for lines, the influence of the reactive power loss of lines to the power grid voltage is reduced, and the stability of the sending end and receiving end power grids is improved.
Owner:XJ ELECTRIC +3
Single-phase and three-phase conversion system based on MMC units
InactiveCN103997232AEnables two-way power transferImprove efficiencyAc-ac conversionCapacitanceLow voltage
Disclosed is a single-phase and three-phase conversion system based on MMC units. Each MMC unit is formed by connecting 10 bridge arms, wherein four bridge arms constitute a single-phase inverter and form a single-phase alternating-current port, and the other six bridge arms constitute a three-phase inverter and form a three-phase alternating-current port. Each MMC bridge arm is formed by connecting p structurally-identical power modules and an MMC bridge arm inductor L in series. The power modules are of a single-phase half bridge structure and are respectively composed of an IGBT half bridge and a direct-current energy storage capacitor. The single-phase alternating-current ports of n MMC units are connected in series with a high-voltage system. The three-phase alternating-current ports of the MMC units are insulated from each other and are independently connected with a low-voltage system. Two-way active power flow between the single-phase high-voltage system and the three-phase low-voltage system is realized. A matching transformer is omitted, which enables the system to have the advantages of small size, light weight, high efficiency, and less investment. The single-phase and three-phase conversion system based on MMC units is advanced and reliable in technology, and is easy to implement.
Owner:SOUTHWEST JIAOTONG UNIV
Who we serve
- R&D Engineer
- R&D Manager
- IP Professional
Why Patsnap Eureka
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com