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.
35results about How to "Solving Harmonic Problems" 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
Microgrid system with asymmetric non-linear load and power balancing control method
InactiveCN105071405ASolving Harmonic ProblemsSolve balance problemsPolyphase network asymmetry elimination/reductionReactive power adjustment/elimination/compensationMicrogridPower balancing
The invention dsiclsoes a microgrid system with an asymmetric non-linear load and a power balancing control method. The system comprises a plurality of DG units connected in parallel and line impedors connected with all DG units. The line impedors are connected to a microgrid bus by PCC points. A three-phase balancing resistive load, an asymmetric linear load, and a diode rectifier non-linear load of a load unit are connected to the microgrid bus by PCC points. A measurement module for measuring voltage fundamental wave positive sequence and negative sequence components and harmonic wave components of the PCC points is also connected to the microgrid bus. The microgrid bus is connected with a 10-kV main power grid by a static switch and a transformer successively. According to the invention, reactive and harmonic power balancing of the microgrid is realized by using a selective virtual impedance based on the virtual fundamental positive and negative sequence impedance and the virtual variable harmonic impedance; a harmonic and unbalancing voltage compensation controller enables equal division of an unbalanced power and a harmonic power to be realized; and a problem of unbalancing of the harmonic wave and the voltage of the microgrid can be solved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
Interconnection detection cloud platform facing electric vehicle charging facilities
ActiveCN109633310AImprove work efficiencyLow costElectrical testingElectric vehicle charging technologyAnalysis centerEngineering
The invention discloses an interconnection detection cloud platform facing electric vehicle charging facilities. The platform is used for a charging facility network access detection, engineering acceptance detection, a business expansion operation detection, a transportation and maintenance detection, compatibility and consistency tests of charging facilities and an electric vehicle and the like;the cloud platform is composed of a detection management center, a knowledge expert database, a data analysis center and a service data interface, and are used for providing support of a detection standard, equipment state analysis, fault analysis and the like for on-site detection personnel, and providing technical support for an industry management equipment platform account, an electric vehicle characteristic library, a charging equipment detection library, a charging equipment fault library, a detection method and the detection standard, and providing professional charging facility detection statistic analysis reports for the national power grid, the government, charging operators and suppliers, and providing a device fault detection report and a diagnosis report interface for the charging operators.
Owner:SHANDONG LUNENG SOFTWARE TECH
Alternating current bus electronic control system of electric workover rig
InactiveCN102751751AAvoid shockImprove cycle lifeBatteries circuit arrangementsSingle network parallel feeding arrangementsFrequency changerSignal on
The invention provides an alternating current bus electronic control system of an electric workover rig. The alternating current bus electronic control system comprises an energy storing battery, a bidirectional direct current / direct current (DC / DC) converter, a pulse-width modulation (PWM) grid-tied current converter, a super capacitor, a one-way DC / DC converter, a frequency converter, measuring units, a controller and other loads of the workover rig. A first measuring unit sends a measured parameter signal on a first direct current bus to a controller and performs charge control, discharge control and protection control to the energy storing battery through sampling inspection. A second measuring unit sends a measured parameter signal on a second direct current bus to the controller, distributes energy on the second direct current bus through sampling inspection and performs protection control to a frequency converter. The controller is respectively connected with the DC / DC converter, the PWM grid-tied current converter, the one-way DC / DC converter, the measuring units and the frequency converter and controls operation of parts. By means of the alternating current bus electronic control system, the existing problems including harmonic waves, load power optimal coordination and distribution, energy feedback, impact of the energy storing battery, starting current impact of an electric motor and the like can be solved.
Owner:CHINA UNIV OF PETROLEUM (BEIJING) +1
DC supply mode of LED street lamp
InactiveCN102118906ASimple structureImprove reliabilityAc-dc conversion without reversalElectric light circuit arrangementLow voltageTransformer
The invention relates to a DC supply mode of an LED street lamp and belongs to the field of low-voltage power supply and distribution. A DC power supply system comprises a DC power station composed of a street lamp transformer (1), a rectifier filter (2) and a reactive power compensator (3), a DC transmission line, an LED street lamp driving power supply (4) and the like. With the advancement of the LED light source technology, the service life of the light source exceeds 50, 000 hours, the consumption of electric energy is lower than one half of that of a conventional light source, the LED street lamp technology gradually comes into practice, and the LED light source is more and more widely used; the working mode of the conventional LED street lamp is as follows: each lamp is provided with a driving power supply for converting alternating current into direct current, so that the LED light source emits light; the single-phase rectifier, the filter capacitor and the PFC (power factor correction) circuit in the power supply are the bottleneck of popularization and application of the LED street lamp due to shorter service life besides harmonic pollution; and to fully exert the advantages of the LED light source with energy conservation and long service life, the invention provides a solution for DC supply mode of the LED street lamp, electric energy is provided for the LED street lamp by the DC supply mode, and the rectifier bridge, the filter capacitor and the PFC circuit in the conventional power supply are saved, so that the purpose of long-term secure and reliable operation of the LED street lamp is achieved.
Owner:叶明宝
Alternating current signal effective value measuring device
ActiveCN105548667ASolve the problem with DC componentSolving Harmonic ProblemsEffective value measurementsMeasurement deviceEngineering
The invention provides an alternating current signal effective value measuring device which comprises an absolute value conversion circuit, a high-frequency triangular wave generation circuit, a PWM signal modulation circuit, a front-end integral circuit, a rear-end integral circuit, a reset circuit, a sampling maintaining circuit, a dividing circuit, a root circuit and a timing circuit. According to the alternating current signal effective value measuring device, the absolute value | v(t) / of signals to be tested v(t) and single-polarity symmetric high-frequency triangular wave signal v(t) are subjected to modulation, and high-frequency PWM signals far higher than the v(t) frequency are obtained; due to the fact that v(t) are continuous signals, and vc(t) frequency is far higher than v(t), the area of the PWM signals in each cycle is equal to the area formed by the| v(t) / in the corresponding PWM signal cycle; meanwhile, v(t)<2> is also a continuous function, so that the effective value of v(t) can be obtained by calculating the square and evolution of the PWM signals in the cycle T of v(t). According to the alternating current signal effective value measuring device, the alternating signals v(t) for calculating the effective value are all alternating cycle signals, namely alternating current cycle signals containing direct current components and alternating current components, so that the alternating current signal effective value measuring device can effectively solve the problem that the signal to be tested contains direct current components and harmonic waves and is wider in application range.
Owner:爱科赛智能科技(浙江)有限公司
Active damping optimization method for grid-connected current control of L-type grid-connected inverter
ActiveCN108321842ASolving Harmonic ProblemsFix stability issuesLoad forecast in ac networkSingle network parallel feeding arrangementsResearch ObjectIntermediate frequency
The invention discloses an active damping optimization method for grid-connected current control of an L-type grid-connected inverter, which solves the problem that the control system is unstable dueto the existence of a digital control delay, and solves the problem of insufficient mid-band phase margin due to a compensation delay. The active damping optimization method includes the following steps: obtaining a difference delta ie of a beat delay output of a current reference preset value iL_ref and an actual current sampled value iL sampled by the system; adding a current prediction method,using the predicted inductor current as a research object, and compensating the delay link. The active damping optimization method is added to a current loop, which essentially adds a second-order differential feedback link into the current loop, the problem that the active high-frequency damping method is added to cause instable mid-frequency band of the system can be solved; a resonance peak caused by a system delay is suppressed; the stability of the system is improved; the gain range of current control is expanded; and dynamic and static errors of the system are reduced.
Owner:XIAN UNIV OF TECH
Speed sensor-less control method and system for permanent magnet synchronous motor
ActiveCN107508521AAccurate outputDoes not affect the fundamental componentElectronic commutation motor controlElectric motor controlMotor speedIntegrator
The invention discloses a speed sensor-less control method and system for a permanent magnet synchronous motor. The method includes steps of: obtaining three-phase voltage and three-phase current of the permanent magnet synchronous motor, and performing Clark conversion of the three-phase voltage and the three-phase current of the permanent magnet synchronous motor to obtain equivalent current and equivalent voltage of the permanent magnet synchronous motor in the [alpha][beta]-axis coordinate system; obtaining the counter electromotive force of the motor in the [alpha][beta]-axis coordinate system according to the equivalent voltage and the equivalent current in the [alpha][beta]-axis coordinate system; placing the counter electromotive force of the motor in the [alpha][beta]-axis coordinate system into a high-order generalized integrator to automatically eliminate the direct current component and the alternating current component in the counter electromotive force of the motor, and then obtaining the rotor flux in the [alpha][beta]-axis coordinate system; based on the rotor flux in the [alpha][beta]-axis coordinate system, extracting the rotor position and motor speed, and driving the permanent magnet synchronous motor to operate. The method and the system have the advantages of high precision of dynamic steady state control and good parameter robustness, and improve the control accuracy and operation reliability of the speed sensor-less control of the permanent magnet synchronous motor.
Owner:HUAZHONG UNIV OF SCI & TECH
Direct hanging type large-capacity electric energy quality comprehensive managing device for electrified railway
ActiveCN103560508AFlexible configurationLow costReactive power adjustment/elimination/compensationReactive power compensationHarmonicActive compensation
The invention discloses a direct hanging type large-capacity electric energy quality comprehensive managing device for an electrified railway. The direct hanging type large-capacity electric energy quality comprehensive managing device comprises an active compensation system and a passive compensation system. The passive compensation system comprises two passive high-pass filters for filtering higher harmonics out and providing partial capacitive reactive power, and the active compensation system is formed by connecting a plurality of active compensation units in parallel. The direct hanging type large-capacity electric energy quality comprehensive managing device has the advantages of being simple in structure, low in cost, good in reliability, capable of solving various electric energy quality problems and the like.
Owner:ZHUZHOU NAT ENG RES CENT OF CONVERTERS
Antenna connecting device, antenna assembly and electronic equipment
ActiveCN113381167AWill not reduce heightDistance will not decreaseSimultaneous aerial operationsAntenna supports/mountingsComputer hardwarePersonal computer
The embodiment of the invention provides an antenna connecting device, an antenna assembly and electronic equipment. The electronic equipment can be a mobile phone, a tablet personal computer, a notebook computer, a super mobile personal computer (UMPC), a handheld computer, an interphone, a netbook, a POS machine, a personal digital assistant (PDA), a wearable device, a virtual reality device, a wireless USB flash disk, a Bluetooth loudspeaker / earphone, a vehicle-mounted front part or other mobile or fixed terminals with antennas. Through the antenna connecting device, non-contact coupling connection between the antenna and the feeding point or the grounding point is realized, arrangement of an elastic bonding pad or a flexible metal buffer material on the antenna is avoided, arrangement of an elastic pin and a flexible metal buffer material on the feeding point or the grounding point is avoided, and the cost of antenna connection is reduced; and the occupied space of the antenna connecting device in the mobile phone is reduced.
Owner:HONOR DEVICE CO LTD
A netted floating wave energy generating device and its working method
ActiveCN107143459BStable outputSolving Harmonic ProblemsWaterborne vesselsHydro energy generationEngineeringOmni directional
The invention provides a reticulation floating-type wave energy power generation device. The device comprises a power generation array composed of multiple wave energy power generation units, the power generation array is shaped like an orthogonal grid, each wave energy power generation unit is equipped with an independent power generator and a float cabin of an electrical energy conversion processing unit, the power generation array is floated on water surface, the relative vertical position of each power generation unit changes under the action of waves and connection components are driven to make rotations, the independent power generator inside the float cabin is driven to generate power after the speed acceleration by an acceleration mechanism, and finally through the float cabin, power conversion is conducted, and output to an energy storage system or an external load is conducted through processing units. By the reticulation floating-type wave energy power generation device, the omni-directional wave absorption of the wave energy can be achieved, the absorption efficiency is high, and the capacity of resistance to wind is strong.
Owner:TIANJIN UNIVERSITY OF TECHNOLOGY
Microgrid system with asymmetric nonlinear load and power balance control method
InactiveCN105071405BSolving Harmonic ProblemsSolve balance problemsPolyphase network asymmetry elimination/reductionReactive power adjustment/elimination/compensationMicrogridPower balancing
The invention discloses a microgrid system with an asymmetric nonlinear load and a power balance control method. The system includes a plurality of parallel DG units and line impedances respectively connected to each DG unit. The line impedance is connected to the microgrid through a PCC point. On the power grid bus, the three-phase balanced resistive load, asymmetric linear load and diode rectified nonlinear load of the load unit are all connected to the microgrid bus through the PCC point, and the microgrid bus is also connected to the positive sequence for measuring the fundamental voltage of the PCC point. , negative sequence component and harmonic component measurement module, the microgrid bus is connected to the 10kV main grid through static switches and transformers in turn. The invention utilizes the selective virtual impedance based on the virtual fundamental wave positive sequence, negative sequence impedance and virtual variable harmonic impedance to realize the reactive power and harmonic power balance of the microgrid, and the harmonic and unbalanced voltage compensation controller can realize unbalanced The equal sharing of balanced power and harmonic power solves the problem of microgrid harmonic and voltage imbalance.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
High-voltage direct current distribution system for captive balloon
ActiveCN108134411AImprove power transmission capacityReduce weightElectric power transfer ac networkHigh-voltage direct currentDistribution power system
The present invention discloses a high-voltage direct current distribution system for a captive balloon. The system comprises an aboveground power supply portion and an on-balloon power supply and distribution portion; the aboveground power supply portion comprises an alternating current supply network which is connected with an AC / DC rectifier; the aboveground power supply portion and the on-balloon power supply and distribution portion are connected through a high-voltage direct current cable, and an input end of the high-voltage direct current cable is connected with an output end of the AC / DC rectifier; the on-balloon power supply and distribution portion is configured to perform power supply and distribution for an on-balloon device, wherein the on-balloon device comprises an on-balloon DC / DC converter set, a load converter set and an on-balloon integrated distribution unit; and an output end of the on-balloon integrated distribution unit is connected with a balloon device and a load device, a direct current bus of the balloon device is distributed to the balloon device through the on-balloon integrated distribution unit, and electric energy output by the load converter set isdistributed to the load device through the on-balloon integrated distribution unit. The high-voltage direct current distribution system for the captive balloon can effectively improve the transmission capability of the high-voltage cable, reduce weight of the on-balloon power supply and distribution portion, simplify a power supply and distribution device and improve the system reliability.
Owner:CHINA ELECTRONIC TECH GRP CORP NO 38 RES INST
Mixed-type multifunctional direct current large-current ice melting device
ActiveCN106953287AAddress reliabilitySolve the problem of energy consumptionOverhead installationReactive power adjustment/elimination/compensationFull bridgeEngineering
The present invention relates to the high-voltage transmission and distribution system technology field, the structure is simple, and the usage is convenient. The full-bridge MMC converter of the mixed-type multifunctional direct current large-current ice melting device and the alternating current side of a thyristor direct current ice melting device are connected with the alternating current bus of a power supply; the positive electrode and the negative electrode of the direct current side of the thyristor direct current ice melting device are connected with the direct current buses of the positive electrode and the negative electrode through a disconnecting link K4 and a direct current smoothing reactor; the positive electrode of the direct current side of the full-bridge MMC converter is connected with the positive electrode direct current bus through a disconnecting link K1, and the direct current side negative electrode of the full-bridge MMC converter is connected with the negative direct current bus through a disconnecting link K2; a disconnecting link K3 is crossed between the positive electrode direct current bus and the negative electrode direct current bus, two ends of a disconnecting link K6 are respectively connected with nodes between the disconnecting link K4 and the direct current smoothing reactor and between a disconnecting link K5 and the direct current smoothing reactor; and the positive electrode direct current bus and the negative electrode direct current bus are connected with two phases of the power transmission line being subjected to ice melting through a disconnecting link K7 and a disconnecting link K8, and the tail ends A, B and C phases of the power transmission line being subjected to ice melting are in short connection.
Owner:ZHEJIANG GUIRONG XIEPING TECH
A Method of Measuring RMS Value of AC Signal Based on PWM
ActiveCN105699738BSolving Harmonic ProblemsHigh precisionEffective value measurementsArray data structureHarmonic
The invention provides a PWM-based AC signal effective value measurement method. The method comprises the steps of (1) conducting the absolute conversion on a to-be-measured AC periodic signal v(t) to obtain |v(t)|; (2) generating a centrally symmetrical triangular wave vc (t) by a triangular wave signal generator; (3) subjecting vc (t) and |v(t)| to the PWM modulation treatment to obtain a corresponding PWM modulation signal (img file='DDA000093622208000011.tif' wi='128' he='62' / ); (4) converting the zero point of the signal |v(t)| into an edge pulse signal vp(t); (5) capturing the falling edge of the edge pulse signal vp(t) by means of a controller, measuring the period T of the vc (t) and the conduction time (img file='DDA000093622208000013.tif' wi='85' he='68' / ) of the (img file='DDA000093622208000012.tif' wi='98' he='61' / ), storing the obtained result in an array Ton[K], and calculating the effective value (img file='DDA0000936222080000014.tif' wi='592' he='148' / ) of the to-be-measured AC periodic signal v(t). According to the technical scheme of the invention, the effective values of all AC periodic signals v(t) can be calculated, particularly AC periodic signals including DC components and harmonic components. Therefore, the problem of DC components and harmonic components in to-be-measured signals can be effectively solved. As a result, the method is wider in application range.
Owner:爱科赛智能科技(浙江)有限公司
Interconnection detection cloud platform for electric vehicle charging facilities
ActiveCN109633310BImprove work efficiencyLow costElectrical testingElectric vehicle charging technologyAnalysis centerElectric vehicle
The invention discloses an interconnection and intercommunication detection cloud platform for electric vehicle charging facilities, charging facility network access detection, engineering acceptance detection, business expansion and installation business detection, operation and maintenance detection, charging facility and electric vehicle compatibility and consistency test Wait. The cloud platform consists of four parts: inspection management center, knowledge expert database, data analysis center, and business data interface, which respectively provide inspection standards, equipment status analysis, fault analysis and other basis for on-site inspectors; provide industry management equipment account, electric vehicle Provide technical support for feature database, charging equipment detection database, charging equipment failure database, detection methods and detection standards; provide professional charging facility detection statistical analysis reports for State Grid, government, charging operators and suppliers; provide equipment for charging operators Fault detection report and diagnosis report interface.
Owner:SHANDONG LUNENG SOFTWARE TECH
A high-voltage direct current transmission and distribution system for tethered balloons
ActiveCN108134411BImprove power transmission capacityReduce weightElectric power transfer ac networkHigh-voltage direct currentDistribution power system
Owner:CHINA ELECTRONIC TECH GRP CORP NO 38 RES INST
High-voltage direct-current urban rail transit traction power supply system
ActiveCN111146823AImprove power densityOptimize quantityLoad balancing in dc networkPower supply linesDC - Direct currentTerminal voltage
According to a high-voltage direct-current urban rail transit traction power supply system, the input voltage of a main substation is converted into + / -10 kV or direct currents of other voltage classes and distributed to all traction substations, the output positive voltage of a direct traction station is connected to a traction network, and the output zero voltage of the direct traction station is connected to a walking rail. If a negative voltage output by the direct traction station is connected to the return line and the three-end voltage output by the direct current AT in the direct current autotransformer station is respectively connected to the traction network, the running rail and the return line, the direct current AT power supply system is formed. The multifunctional DC transformer in the direct traction station can realize bidirectional energy flow, so that high-voltage DC buses of stations such as a main substation, the direct traction station and a direct coupling stationand all DC capacitors on a traction network can be used as energy buffers during train braking, and the problem of train braking energy utilization is solved from the source. In addition, the systemcan effectively reduce rail potential and stray current.
Owner:BEIJING JIAOTONG UNIV +1
A device and method for suppressing harmonics of electron tube amplifier
ActiveCN106301245BNo reduction in powerSolving Harmonic ProblemsAmplifier modifications to reduce noise influenceHigh frequency amplifiersAudio power amplifierHarmonic
Owner:HEFEI CAS ION MEDICAL & TECHNICAL DEVICES CO LTD
Mobile outdoor high-voltage active filtering apparatus
InactiveCN106374467AGood securitySolve system harmonic problemsActive power filteringAc network to reduce harmonics/ripplesActive power filterHigh pressure
The invention relates to a mobile outdoor high-voltage active filtering apparatus. The mobile outdoor high-voltage active filtering apparatus comprises a body; a main casing installed on the body; a power supply module installed on the body; and a high-voltage active power filter which is installed in the main casing and is connected with the power supply module. Compared to the prior art, the apparatus has the advantages of effectively solving the problem of system harmonic waves of a remote region, being good in safety and wide in application scope, and the like.
Owner:LIVESINE ELECTRIC SHANGHAI CO LTD
Reconstruction method of harmonically polluted distribution network based on forward/backward sweep harmonic power flow
ActiveCN112134288BEasy to handleAccurate processingAc networks with different sources same frequencyTotal harmonic distortionReconstruction method
Harmonic pollution power distribution network reconstruction method based on forward / backward sweep harmonic power flow, input load network data; build a connection matrix, calculate the sum of each column, and judge whether the load network has an available end bus; starting from the end bus, According to the end bus load, determine the end branch current and flow direction, then ignore the end bus and its connected branches, update the connection matrix, and add the ignored branch current to the corresponding sending end bus; according to the method of forward / backward scanning , determine the flow direction of the branch while detecting the ring structure; the harmonic voltage drop of each bus relative to the first bus corresponds to its harmonic voltage, and the harmonic voltage of the load network is calculated; from the perspective of the load, according to the specified harmonic order The load impedance of the connection is calculated, and the bus harmonic voltage is calculated; the simulation analysis is performed to obtain the total harmonic distortion of the voltage; the distribution network is reconstructed. The method of the present invention considers the radial topology of the network, and has higher computational efficiency compared with the existing method.
Owner:国网江苏省电力有限公司滨海县供电分公司 +3
An Electromagnetic Hybrid Compensation System for Power Quality of Electrified Railway
InactiveCN103545825BSolve balance problemsSolving Harmonic ProblemsFlexible AC transmissionReactive power adjustment/elimination/compensationPower qualityEngineering
Owner:WUHAN UNIV
Hybrid Multifunctional DC High Current Ice Melting Device
ActiveCN106953287BAddress reliabilitySolve the problem of energy consumptionOverhead installationReactive power adjustment/elimination/compensationFull bridgeEngineering
The present invention relates to the high-voltage transmission and distribution system technology field, the structure is simple, and the usage is convenient. The full-bridge MMC converter of the mixed-type multifunctional direct current large-current ice melting device and the alternating current side of a thyristor direct current ice melting device are connected with the alternating current bus of a power supply; the positive electrode and the negative electrode of the direct current side of the thyristor direct current ice melting device are connected with the direct current buses of the positive electrode and the negative electrode through a disconnecting link K4 and a direct current smoothing reactor; the positive electrode of the direct current side of the full-bridge MMC converter is connected with the positive electrode direct current bus through a disconnecting link K1, and the direct current side negative electrode of the full-bridge MMC converter is connected with the negative direct current bus through a disconnecting link K2; a disconnecting link K3 is crossed between the positive electrode direct current bus and the negative electrode direct current bus, two ends of a disconnecting link K6 are respectively connected with nodes between the disconnecting link K4 and the direct current smoothing reactor and between a disconnecting link K5 and the direct current smoothing reactor; and the positive electrode direct current bus and the negative electrode direct current bus are connected with two phases of the power transmission line being subjected to ice melting through a disconnecting link K7 and a disconnecting link K8, and the tail ends A, B and C phases of the power transmission line being subjected to ice melting are in short connection.
Owner:ZHEJIANG GUIRONG XIEPING TECH
High Voltage DC Urban Rail Transit Traction Power Supply System
ActiveCN111146823BImprove power densityOptimize quantityLoad balancing in dc networkPower supply linesDC - Direct currentTerminal voltage
Owner:BEIJING JIAOTONG UNIV +1
Active damping optimization method for grid-connected current control of l-type grid-connected inverter
ActiveCN108321842BSolving Harmonic ProblemsFix stability issuesLoad forecast in ac networkSingle network parallel feeding arrangementsGrid connected inverterControl system
The invention discloses an active damping optimization method for grid-connected current control of an L-type grid-connected inverter, which solves the problem of instability of the control system due to the existence of digital control delay, and solves the problem caused by compensation delay The problem of insufficient phase margin in the mid-band. It specifically includes the following steps: Obtain the current reference given value i according to the system sampling L_ref and actual current sampling value i L The difference Δi of the one-beat delay output e . The current prediction method is added, and the predicted inductor current is taken as the research object, and the delay link is compensated. The essence of adding an active damping optimization method to the current loop is to add a second-order differential feedback link to the current loop, which solves the problem that the addition of the active high-frequency damping method causes the system The resonance peak caused by the time improves the system stability, expands the current control gain range, and reduces the system dynamic and static errors.
Owner:XIAN UNIV OF TECH
Alternating current bus electronic control system of electric workover rig
InactiveCN102751751BAvoid shockImprove cycle lifeBatteries circuit arrangementsSingle network parallel feeding arrangementsFrequency changerElectrical battery
The invention provides an alternating current bus electronic control system of an electric workover rig. The alternating current bus electronic control system comprises an energy storing battery, a bidirectional direct current / direct current (DC / DC) converter, a pulse-width modulation (PWM) grid-tied current converter, a super capacitor, a one-way DC / DC converter, a frequency converter, measuring units, a controller and other loads of the workover rig. A first measuring unit sends a measured parameter signal on a first direct current bus to a controller and performs charge control, discharge control and protection control to the energy storing battery through sampling inspection. A second measuring unit sends a measured parameter signal on a second direct current bus to the controller, distributes energy on the second direct current bus through sampling inspection and performs protection control to a frequency converter. The controller is respectively connected with the DC / DC converter, the PWM grid-tied current converter, the one-way DC / DC converter, the measuring units and the frequency converter and controls operation of parts. By means of the alternating current bus electronic control system, the existing problems including harmonic waves, load power optimal coordination and distribution, energy feedback, impact of the energy storing battery, starting current impact of an electric motor and the like can be solved.
Owner:CHINA UNIV OF PETROLEUM (BEIJING) +1
Control method for double closed-loop cascade in synchronous revolution coordinates system
ActiveCN101373897BSolving Harmonic ProblemsOvercoming the problem of low utilization rate of DC measuring voltageActive power filteringHarmonic reduction arrangementClosed loopEngineering
The invention relates to a double closed-loop cascade control method based on synchronous rotating coordinates, which adopts a double closed-loop cascade control policy with an outer voltage loop and an inner current loop, transforms through a phase locking and rotational coordinates, and comprises the steps such as outer loop pressure regulation, network voltage feedforward, instruction extraction, inner loop current regulation, three-dimensional vector generator collection processing, etc. The double closed-loop cascade control method not only solves the harmonic problem which commonly exists in the comprehensive application of the power electronic technology very effectively, but also overcomes the problem that the utilization ratio is low when measuring the voltage by using a direct current in the existing three phase four wire type active power filter system, thereby creating the technical support for the lectotype range expansion of power devices and safety of all devices of theentire running network system at the same time.
Owner:博格华纳新能源(襄阳)有限公司
Control circuit, control method, circuit board, air conditioner and storage medium
PendingCN114337330AAvoid overvoltage failureSimple designSpace heating and ventilation safety systemsLighting and heating apparatusAC - Alternating currentControl engineering
The invention provides a control circuit, a control method, a circuit board, an air conditioner and a storage medium, the control circuit comprises a Vienna circuit and a controller, the Vienna circuit is provided with three alternating current input ends and three groups of bidirectional switches, and the alternating current input ends and the bidirectional switches are in one-to-one correspondence; each group of bidirectional switches comprises a first switching device and a second switching device which are connected in series; the controller is connected to the first switching device and the second switching device; the controller is used for acquiring an electric signal of each alternating current input end and controlling the first switching device and the second switching device in the bidirectional switch corresponding to the alternating current input end of which the waveform of the electric signal is in a positive half cycle to be normally opened or normally closed; and controlling the second switching device in the bidirectional switch corresponding to the alternating current input end of which the waveform of the electric signal is in the negative half cycle to alternately switch and the first switching device to be normally opened or normally closed. According to the invention, the rectification effect can be better controlled and realized, and the normal operation of electric appliances is ensured.
Owner:CHONGQING MIDEA REFRIGERATION EQUIP CO LTD +1
Electronic control system of electric workover rig
InactiveCN102751943BReduce pollutionAchieving Unity Power FactorAC motor controlTransformerAlternating current
The invention provides an electronic control system of an electric workover rig. The electronic control system comprises a pulse-width modulation (PWM) rectifier, an energy storing battery, a bidirectional direct current-direct current (DC / DC) converter, a variable frequency inverter, a controller, a hydraulic system and a pneumatic system. The PWM rectifier is connected with a well field transformer and used for outputting constant voltage or constant current. The variable frequency inverter is connected with the PWM rectifier and used for driving an electric motor to operate in a loading mode. The energy storing battery is connected to a direct current bus between the variable frequency inverter and the PWM rectifier through the DC / DC converter, wherein the DC / DC converter is used for controlling charging and discharging functions of the energy storing battery and outputting bidirectional stable voltage. The hydraulic system and the pneumatic system are connected to an alternating current bus between the PWM rectifier and the well field transformer and used for loading. The controller is used for being connected with the PWM rectifier, the variable frequency inverter and the bidirectional DC / DC converter, detecting diameter information of parts and controlling operation of the parts. The electronic control system of the electric workover rig can solve the existing problems including harmonic wave, load power optimal coordination distribution and energy feedback in the prior art.
Owner:CHINA UNIV OF PETROLEUM (BEIJING) +1
Converter switching frequency control method and system
ActiveCN110943602ASolve the problem that the process of harmonic improvement method is relatively cumbersomeReduce switching frequencyEfficient power electronics conversionPower conversion systemsControl mannerControl system
The invention relates to a converter switching frequency control method and system, and the method comprises the steps: firstly detecting actual harmonic content of a converter, then comparing the actual harmonic content with a set content threshold value, and controlling to improve the switching frequency of the converter when the actual harmonic content is greater than the set content thresholdvalue and the converter is in a seven-segment control mode; and when the actual harmonic content is less than or equal to the set content threshold and the switching frequency of the converter is greater than the minimum allowable switching frequency, controlling to reduce the switching frequency of the converter. When grid-connected stable operation of the converter can be ensured, according to the change condition of the harmonic content output by the grid-connected point, the working mode and the switching frequency of a switching device of the converter are correspondingly controlled and changed, it is guaranteed that the converter has small harmonic content within the full-power output range, low-harmonic and high-efficiency operation within the full-power interval of the converter isachieved, and the working efficiency of the converter is improved.
Owner:XUJI GRP +3
A converter switching frequency control method and control system
ActiveCN110943602BSolve the problem that the process of harmonic improvement method is relatively cumbersomeReduce switching frequencyEfficient power electronics conversionPower conversion systemsControl systemControl manner
The invention relates to a switching frequency control method and control system of a converter. First, the actual harmonic content of the converter is detected, and then the actual harmonic content is compared with the threshold value of the set content. When the actual harmonic content is greater than the set content threshold, and the converter is a seven-stage control mode, the control increases the switching frequency of the converter; when the actual harmonic content is less than or equal to the set content threshold, and the switching frequency of the converter is greater than the minimum allowable switching frequency, the control Reduce the converter switching frequency. Through this control method, under the condition that the converter can be connected to the grid and run stably, according to the change of the harmonic content output from the grid-connected point, the working mode and switching frequency of the switching device of the converter can be controlled and changed accordingly, so as to ensure the In the full power output range of the converter, it has a small harmonic content, which realizes low harmonic and high efficiency operation in the full power range of the converter, and improves the working efficiency of the converter.
Owner:XUJI GRP +3
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