1111results about "Load balancing in dc network" patented technology

The invention discloses a DC bus voltage fluctuation suppression method of a renewable energy hydrogen production system, and relates to the technical field of renewable energy electrolysis hydrogen production. The method comprises the following steps: collecting system operation parameters in real time; bus voltage disturbance power is estimated based on a disturbance observer, and frequency decomposition is carried out; fusing the ARIMA model and the LSTM model to predict the load power, and calculating a prediction deviation; dynamically setting upper and lower limits of a bus voltage control interval according to the predicted deviation and the operation state; a multi-objective optimization function is constructed, bus voltage disturbance power, prediction deviation and a control limit value are comprehensively considered, and power regulation instructions of battery energy storage, a fuel cell and an electrolytic cell are solved; and executing power regulation control to realize bus voltage stabilization. The method can improve the grading response capability of voltage disturbance, the prediction accuracy of load power change, the adaptability of the control boundary and the overall operation stability of the system, and is suitable for the electric energy quality control of the hydrogen production system in a multi-source fluctuation scene.

The invention relates to the technical field of hydrogen production, in particular to a micro-grid hydrogen production system based on dynamic optimization control and a multi-mode energy scheduling method. Comprising a renewable energy power generation unit which comprises at least two distributed power supplies with different power generation characteristics; the multi-stage hydrogen production device is configured to receive the electric energy output of the renewable energy power generation unit and perform proton exchange membrane water electrolysis hydrogen production; the hybrid energy storage system comprises a super capacitor bank and a lithium ion battery pack which are connected in parallel to the direct current bus through a bidirectional DC / DC converter; the dynamic optimization controller is internally provided with a multi-time-scale coordination algorithm and is used for acquiring meteorological prediction data, load demand data and an energy storage SOC state in real time; the multi-mode scheduling module comprises three working modes including an island operation mode, a grid-connected operation mode and an emergency standby mode; according to the scheme, hydrogen production economy, equipment durability and power supply reliability can be considered at the same time.

The invention provides a self-adaptive constraint model active mismatch prediction control method based on voltage and current ripple resistance of a power converter in a hybrid energy storage system, and the method comprises the steps: building an island DC micro-grid system model, collecting the voltage and current information of a system, and designing a model prediction control frame of a power loop and a cost function of the model prediction control frame; designing a model predictive control framework of the current loop and a cost function of the model predictive control framework; designing an active model mismatch mechanism to enhance the response capability to dynamic change; determining an optimization problem with a normal value, and designing an adaptive constraint optimization algorithm to dynamically adjust constraint parameters and optimize control performance; and designing a steady-state and dynamic-mode trigger for adapting to the running state of the system. According to the invention, the trajectory tracking precision of the system under dynamic and steady-state working conditions can be significantly improved, current ripples caused by control delay can be effectively eliminated, damage to electrical equipment due to overlarge ripples can be avoided, and the service life of the equipment can be prolonged.

The invention discloses a hybrid hydrogen production system coupled with photovoltaic renewable energy and an optimal configuration method, and relates to the technical field of new energy utilization and energy storage control, and the hybrid hydrogen production system comprises a photovoltaic power generation unit, an alkaline water electrolytic tank unit, a proton exchange membrane electrolytic tank unit, a hydrogen storage unit, a control unit and the like. Photovoltaic electric energy is directly supplied to the two types of electrolytic cell stacks through the direct current bus, a traditional DC-DC power converter is omitted, and loss in the energy transmission process is reduced; and through a dynamic electrolytic cell switching algorithm configured by the control unit, the input proportion and the number of operation units of the two stacks are changed and adjusted in real time, and the quick response capability and the long-term stability are both considered. The system can stably produce hydrogen under the condition of renewable energy fluctuation, can dynamically adapt to input power change, can realize maximum power point tracking control on the premise of not using extra power conversion equipment, and remarkably reduces initial investment cost and operation energy consumption while ensuring hydrogen production efficiency.

The invention discloses a wind and light off-grid hydrogen production two-stage power optimization method considering reserved energy of energy storage, and belongs to the technical field of wind and light off-grid hydrogen production system power optimization, and the technical scheme is that the method comprises the following steps: S1, establishing a wind and light off-grid hydrogen production system mathematical model; s2, inputting minute-level wind and light historical data; s3, formulating a power distribution rule considering deep coupling of an electrolytic bath operation condition and energy storage preparation energy in a first operation stage, and determining hydrogen production power and hybrid energy storage initial distribution power; and S4, in the second operation stage, with the minimum unit hydrogen production cost and the minimum average charge and discharge depth of the storage battery as targets, the hybrid energy storage power is optimized by adopting an improved multi-target particle swarm algorithm. The method has the beneficial effects that the hydrogen production stability and the energy storage and power supply capacity can be improved, and the wind and light abandoning rate and the unit hydrogen production cost can be reduced.

The invention provides an AC / DC hybrid microgrid multi-target scheduling method and system based on digital twinning, and relates to the technical field of microgrid scheduling, and the method comprises the following steps: building an AC / DC hybrid microgrid digital twinning model, and dynamically integrating the related data of a power grid; establishing a comprehensive total cost model of the small AC / DC hybrid micro-grid system; according to the method, three power generation modes of photovoltaic power generation, photo-thermal power generation and wind power generation and an energy storage device are combined, and an equipment dynamic efficiency model is established based on the influence of factors such as a local load and an external large power grid environment on the efficiency of AC / DC hybrid micro-grid equipment; various twin data such as a local load and an external large power grid environment are obtained through a digital twin model, a multi-target particle swarm algorithm based on an improved archive maintenance strategy and a fuzzy decision method is proposed with economic benefits and the health degree of the energy storage device as targets, the output condition of the energy storage device is dispatched and optimized in real time, and the output efficiency of the energy storage device is improved. And the multi-energy complementation and conversion capability of the system is improved.

The invention discloses a micro-grid system based on a direct current bus and a control method, the micro-grid system comprises the direct current bus, an energy management unit and a plurality of power conversion modules, when the micro-grid system is in an independent adjusting mode, each power conversion module controls the direct current bus to operate according to bus operation parameters of the direct current bus; and when the micro-grid system is in a centralized regulation mode, the energy management unit issues a control instruction to coordinate the output power and / or the input power of each power conversion module. According to the technical scheme, a unified direct current bus framework is constructed, the photovoltaic energy unit, the energy storage energy unit, the commercial power energy unit, the direct current load and other loads are directly connected to the direct current bus, direct current direct supply and direct current direct charging are achieved, the energy link structure is simplified, the power conversion link is reduced, the overall energy efficiency of the system is improved, and the system cost is reduced. And the phenomena of multiple energy conversion and energy loss caused by dependence on an alternating current bus in the prior art are avoided.

A locomotive comprises a DC power bus, traction motors, batteries, and a charging source, but has no prime mover engine. Each traction motor includes armature and field windings connected in parallel across the DC power bus. The batteries provide power to the DC power bus when in a motoring mode, and receive power from the DC power bus when in a charging mode and a dynamic braking mode. The charging source is connected across the DC power bus to provide charging power to the batteries when in the charging mode. The traction motors also provide charging power to the batteries when in the dynamic braking mode. The power from the charging source is less than the power that would be provided by a prime mover engine. The charging source provides no power to the traction motors when in the charging mode.

The invention discloses a dynamic power distribution method and device for a direct-current micro-grid hybrid energy storage system, and relates to the technical field of electric energy storage management, and the method comprises the steps: collecting the power parameters, load demand fluctuation data and renewable energy power generation output data of each energy storage unit in the hybrid energy storage system in real time, calculating a multi-dimensional power entropy index, and calculating the power entropy index of the hybrid energy storage system; based on the indexes, power distribution weight coefficients are dynamically generated, power dynamic distribution is carried out, a charging and discharging strategy is generated, charging and discharging control of the hybrid energy storage system is executed, and power distribution is dynamically adjusted in combination with a real-time feedback mechanism. The technical problems that an existing energy storage system power distribution method lacks flexibility and cannot effectively cope with load fluctuation and unstable renewable energy sources, so that the system operation efficiency and stability are poor are solved, the charging and discharging strategy of the energy storage unit is dynamically adjusted through the multi-dimensional power entropy index and the real-time feedback mechanism, and the energy storage efficiency is improved. The technical effect of efficient and stable operation of the energy storage system is achieved.

The invention discloses a self-adaptive virtual inertia control and power distribution method of an energy storage converter suitable for a multi-direct-current micro-grid. The method comprises the following steps: establishing a virtual direct-current motor control model; based on the virtual direct current motor control model, designing an adaptive virtual inertial parameter control and power distribution algorithm, so that the energy storage converter can simulate the inertia and damping characteristics of the direct current generator; constructing a small-signal model of the common DC bus of the multi-DC micro-grid, analyzing the influence of inertia and damping parameters on the dynamic performance and stability of the system, and drawing a Nyquist curve based on an impedance ratio criterion to optimize the inertia and damping parameters; and verifying the adaptability of the adaptive virtual inertial parameter control and power distribution algorithm in the multi-direct-current micro-grid, and realizing effective control on the bus voltage stability and the power distribution of the energy storage unit by adjusting the power response characteristic of the energy storage unit. According to the invention, the stability and response speed of the multi-direct-current micro-grid system are improved, the bus voltage fluctuation is effectively slowed down, and the service life of the energy storage unit is prolonged.

The invention relates to the technical field of ship electric energy storage, and discloses a ship distributed electric energy storage and distribution balance control system which comprises a plurality of distributed storage units, a direct current bus, a plurality of power conversion modules and a dynamic balance control module. The dynamic balance control module is used for collecting the voltage deviation value of the direct current bus and the current response rate and the charge state parameter of each storage unit and determining a transient charge deviation compensation value, and the system determines the transient power flux of each node according to the current response rate and the charge state parameter. And dynamic linear calibration of feedback gain is realized based on the charge deviation compensation value so as to adjust the power output flow rate of each storage unit, the charge throughput of the direct current bus is balanced through real-time hedging of the surplus or deficient state of the transient charge of the bus, voltage oscillation during ship propulsion load switching is effectively inhibited, and the reliability of the ship propulsion load switching is improved. And the transient stability of the bus voltage is maintained.

The modular system for hydrogen generation includes a plurality of cores and a hub. Each core includes an electrolyzer and a power supply. The power supply is operable to manage power to the core's electrolyzer and is redundant to the power supply of at least one other of the plurality of cores. The hub includes a water module, a heat exchange module, and a switchgear module. The water module includes a water source in fluid communication with the electrolyzer of each of the plurality of cores, the heat exchange module includes a heat exchanger in thermal communication with the electrolyzer of each of the plurality of cores, and the switchgear module includes a switch activatable to electrically isolate the power supply of each of the plurality of cores.

The invention discloses an AC-DC hybrid microgrid power control method and system, and the method comprises the steps: measuring the operation state quantity of a system at the kth sampling moment of a current control period, and building an AC-side mathematical model of an interconnection converter according to the operation state quantity; according to the operation state quantity of the interconnected converter, judging the power transmission direction of the interconnected converter; a power prediction model is established, and active power and reactive power prediction values at the k + 1 moment are solved in combination with different switching states; calculating a power reference trajectory, and calculating a cost function value corresponding to each switching state by combining the predicted values of the active power and the reactive power; obtaining cost function values under all switching states, selecting the switching state corresponding to the minimum cost function value, and applying the switching state to the bridge arm switching control of the interconnected converter; and entering a next control period, and repeating the steps. According to the invention, bidirectional power mutual assistance between AC and DC hybrid power grids can be realized in multiple scenes of the flexible interconnection hybrid power grid, and the voltage stability is improved.

To provide a modular system for appropriately generating hydrogen, and a method of operating the same.SOLUTION: A modular system for hydrogen generation includes a plurality of cores and a hub. Each core includes an electrolyzer and a power feeder. The power feeder is operable to manage the electric power to the electrolyzer of the core and is redundant to the power feeder of at least the other one of the plurality of cores. The hub includes a water module, a heat exchange module, and a switchgear module. The water module includes a water source in fluid communication with the electrolyzer of each one of the plurality of cores, the heat exchange module includes a heat exchanger in thermal communication with the electrolyzer of each one of the plurality of cores, and the switchgear module includes a switch activatable to electrically isolate the power feeder of each one of the plurality of cores.SELECTED DRAWING: Figure 1A

An electrolyser plant (1A) is described. The electrolyser plant (1A) includes a first DC link (8) with at least one DC link capacitor (C1) and an AC / DC power converter (6). An electrolyser (10) is electrically connected to the first DC link (8) and adapted to receive a load current. During normal operation of the AC power network (2), a controller (12) is adapted to maintain a pre-event DC link voltage and supply a pre-event load current to the electrolyser (10). In response to a detected low voltage event, the controller (12) is adapted to: (a) initially supply the pre-event load current to the electrolyser (10) to maintain normal operation of the electrolyser (10), (b) monitor the DC link voltage, e.g., the voltage in the first DC link (8), and (c) if the monitored DC link voltage falls below a first voltage threshold that is less than the pre-event DC link voltage, reduce the load current supplied to the electrolyser (10), optionally by ramping down the load current at a suitable ramp rate.

The invention discloses an energy equipment control method and system based on a multi-terminal energy router and a medium, and relates to the field of expressways, and the method comprises the steps: collecting the real-time operation data, monitored by the multi-terminal energy router, of multi-terminal energy equipment along the expressway; based on the real-time operation data, constructing an energy network model of multi-terminal energy equipment along the highway; based on the energy network model, analyzing a supply-demand relationship of multi-terminal energy equipment along the highway, and determining an energy scheduling scheme; and based on the energy scheduling scheme, the multi-terminal energy equipment is scheduled through the multi-terminal energy router, and the energy scheduling scheme is dynamically adjusted according to the real-time monitoring result so as to optimize the transmission path and the flow direction of the energy in different scenes. The method can adapt to the dynamic change of the energy demand along the expressway, achieves the optimal scheduling and effective management of the multi-terminal energy equipment, and improves the energy utilization rate.

The invention provides a voltage fluctuation suppression method and device for a subway direct-current power supply system, and the method comprises the steps: obtaining the voltage amplitude change information of the subway direct-current power supply system at different sampling moments, and determining a real-time voltage fluctuation sequence and the operation state characteristics of each power supply node according to the voltage amplitude change information; space-time correlation mapping processing is carried out on the real-time voltage fluctuation sequence and the operation state features, a fluctuation correlation feature set is generated, and the fluctuation correlation feature set comprises voltage fluctuation space-time propagation path features and inter-node coupling influence features; calling a pre-trained fluctuation suppression decision model to perform dynamic suppression strategy generation processing on the fluctuation association feature set to obtain a voltage regulation parameter sequence for each power supply node; according to the voltage regulation parameter sequence and the operation state characteristics of the power supply nodes, generating a node-coordinated fluctuation suppression execution instruction set; and according to the fluctuation suppression execution instruction set, triggering voltage regulation operation of each power supply node to suppress voltage fluctuation.

An apparatus for extending battery life includes a control objective map module configured to derive a mapping between a state of charge (“SOC”) of each battery unit of a plurality of battery units with respect to an average SOC of the battery units. A highest capacity battery unit has a highest discharge amount between a SOC maximum and a SOC minimum and a lowest capacity battery unit has a lowest discharge amount between the SOC maximum and the SOC minimum. Each battery unit is connected to a shared bus through a direct current (“DC”) to DC power converter. The control objective map provides a current reference for a battery unit of the plurality of battery units in relation to a common current of the shared bus. The current reference for the battery unit includes a reference current for the DC to DC power converter connected to the battery unit.

The invention discloses a data center novel full direct current power supply system with multi-energy access, a method, electronic equipment and a storage medium, and the system comprises a 2N + 1 power supply scheme, a power supply from two 110kV buses is constructed into two sections of DC750 direct current buses through a unidirectional rectification link, the two sections of direct current buses can be interconnected for standby through a bus tie switch, and the two sections of direct current buses are connected with each other through a bus tie switch. The two sections of direct current buses convert voltage into DC240V through the DC / DC converter to supply power to the data center server, the power supply reliability of the data center is guaranteed, meanwhile, each section of bus is connected with the DC / DC photovoltaic converter, the AC / DC fan converter, the DC / DC energy storage converter and the AC / DC photovoltaic absorption unit through the direct current switch cabinet, the access capability of new energy is improved, and the power supply reliability of the data center is improved. And the power supply of the data center is further ensured by modifying the operation mode under various working conditions such as upper-level commercial power loss and alternating current system failure.

The invention discloses a wind-solar-storage integrated direct-current micro-grid device and a control method, and relates to the technical field of rural distributed energy. The device comprises a perovskite photovoltaic module array, a vertical axis fan set, a lithium iron phosphate energy storage module, a direct-current power distribution unit, an intelligent control module and a household direct-current terminal, each energy unit and a load are directly connected through a direct current bus, AC / DC conversion loss is reduced, the intelligent control module dynamically adjusts a wind-solar-storage cooperative operation strategy based on illumination, wind speed and electrical load data, and the functions of five-hour stable off-grid power supply and peak-valley arbitrage are achieved. The method adapts to a rural farm house roof resource concentration scene, solves the problems of high loss and poor off-grid stability of a traditional alternating current micro-grid, remarkably improves the energy utilization efficiency, reduces the electricity utilization cost of farmers, and can be widely applied to energy transformation projects in rural areas such as coastal areas.

The invention discloses a dynamic power management method for an all-electric ship hybrid energy storage system. The method comprises the following steps: S1, establishing a direct-current voltage dynamic model and a ship hybrid energy storage system model based on a ship micro-grid structure of a ship; s2, establishing a multi-working-condition propulsion power model based on the movement mechanism of the ship; s3, establishing a joint SOC-SOP estimation model based on the nonlinear relationship among the state of charge, the battery power characteristics and the ambient temperature; s4, on the basis of the direct-current voltage dynamic model, the ship hybrid energy storage system model and the multi-working-condition propulsion power model, establishing a dynamic power distribution model; and S5, estimating an available power range of the battery through a combined SOC-SOP estimation model, inputting the available power range into the dynamic power distribution model, obtaining a dynamic power distribution strategy, and realizing dynamic power distribution of the ship hybrid energy storage system. According to the method, the dynamic power management of the hybrid energy storage system of the all-electric ship under the uncertain navigation condition is optimized, and the stability and the economical efficiency of a ship power system are improved.

A packet energy transfer (PET) receiver comprising receiver front-end circuitry including an input, an output, and at least one switch connected at the output. There is receiver output control and conditioning circuity including an input and an output to be connected to an electrical load. There is a synchronizer circuit to close the switch to allow power to flow into the receiver output control and conditioning circuitry during each of the first plurality of transfer periods of the transmitter and to open the switch to prevent power to flow into the receiver output circuitry during a first plurality of sample periods. There is a load controller that disables the synchronizer circuit and operates the switch to close it and allow power to flow into the receiver output control and conditioning circuitry during subsequent transfer periods and to open the switch to prevent power to flow during a subsequent sample periods.

The invention discloses a light-diesel hybrid energy storage system and a control method thereof, and belongs to the field of microgrids. The system comprises a photovoltaic power generation unit, a diesel generator set, a hybrid energy storage unit (a storage battery and a super capacitor), an AC / DC bus, a bidirectional AC / DC converter and a system controller. The controller executes hybrid energy storage frequency division control (without sampling load power and distributing power through bus voltage), V / f control and nine multi-mode energy management strategies, and monitors parameters such as photovoltaic output, load power, energy storage charge state and the like in real time to realize intelligent mode switching. The super capacitor preferentially responds to the pulse load, and the voltage fluctuation ratio is smaller than or equal to 5%; the service life of the storage battery is prolonged in combination with energy storage charge state threshold management; photovoltaic maximum utilization enables the system efficiency to be greater than or equal to 90%, and the diesel oil consumption is obviously reduced. The method is suitable for power grid coverage difficulty scenes such as off-network communication base stations, remote sentries and emergency power supply stations, and has high reliability and maneuverability.

A system includes a plurality of power modules connected in parallel and a variable current load controller coupled to the plurality of power modules. The input terminals of the plurality of power modules are configured to be coupled to an output of a fuel cell stack, and the output terminals of the plurality of power modules are configured to supply power to a forklift. The plurality of power modules is further configured to provide electrical isolation between the fuel cell stack and the forklift. The variable current load controller is configured to regulate power distribution among the plurality of power modules.

A power backup system is provided for low power outdoor applications. The power backup system comprises a generator, a battery pack, a bus connecting the generator to the battery pack, and a current manager. The battery pack is connected to the bus in a series of parallel conductor paths. A voltage drop across a selected conductor path is different than other voltage drops across the other conductor paths. The current manager is configured to manage current between the generator and the battery pack based on bus voltage.

The invention relates to a method for operating an electrical load (10) in a vehicle electrical system (1) of a vehicle. The electrical load (10) is supplied with electrical energy via a supply line (12) of the vehicle electrical system (1) from an energy source (7) via a distributor module (9) connected between the energy source (7) and the electrical load (10). The distribution module (9) is provided with at least one converter (15) which converts a voltage from the energy source into a low voltage for the electrical load (10), wherein the converter (15) is used to adjust the voltage (18) according to individual requirements of the electrical load (10), wherein the voltage (18) for the electrical load (10) is varied by means of the converter (15) in order to thus transmit information to the electrical load (10), wherein information is transmitted to the electrical load (10) via a data line (13) of the vehicle electrical system (1), wherein the information is transmitted redundantly with respect to the information to the electrical load (10) via the data line (13) by varying the voltage (18). The invention further relates to a corresponding distribution module (9) and to a vehicle electrical system (1) of a vehicle having at least one such distribution module (9).

The present application discloses a power supply and backup network of a communication device. The network includes a medium-low voltage power distribution system, a high voltage battery backup power system, a power distribution system, and a high-voltage direct-current (HVDC) bus system, where the medium-low voltage power distribution system is connected to the power distribution system by the HVDC bus system; the high-voltage battery backup power system is bypassed on the HVDC bus system; the medium-low voltage power distribution system is configured to provide HVDC power for the power distribution system by the HVDC bus system by using input mains power and oil energy backup power; the high-voltage battery backup power system is configured to provide HVDC backup power for the power distribution system by the HVDC bus system; and the power distribution system is configured to distribute, to a connected electrical device, the HVDC power.

The method is applied to the fields of train regenerative braking energy utilization, stray current and rail potential treatment and the like in electrified rail transit, especially urban rail transit. The invention provides a direct-current traction power supply system capable of reducing the energy storage capacity of a super capacitor of urban rail transit, which is combined with a super capacitor energy storage device of the urban rail transit and supplies power to a power electronic device for treating stray current and rail potential by utilizing regenerative braking energy of a train. The super-capacitor energy storage device has the following advantages that on one hand, the energy storage capacity of the super-capacitor bank in the super-capacitor energy storage device between train braking and traction can be reduced, and the utilization efficiency of regenerative braking energy stored by the super-capacitor bank is improved; on the other hand, the problems of stray current, rail potential and the like in the system can be solved from the source, and the power supply distance of a traction substation is remarkably increased. Therefore, the direct-current traction power supply system is of great significance to green and safe operation of urban rail transit.

A locomotive comprises a DC power bus, traction motors, batteries, and a charging source, but has no prime mover engine. Each traction motor includes armature and field windings connected in parallel across the DC power bus. The batteries provide power to the DC power bus when in a motoring mode, and receive power from the DC power bus when in a charging mode and a dynamic braking mode. The charging source is connected across the DC power bus to provide charging power to the batteries when in the charging mode. The traction motors also provide charging power to the batteries when in the dynamic braking mode. The power from the charging source is less than the power that would be provided by a prime mover engine. The charging source provides no power to the traction motors when in the charging mode.

One or more embodiments of the invention provide a power distribution method and device for a multi-machine fuel cell power generation system. The method comprises the following steps: acquiring a corresponding relation between output power and efficiency of each fuel cell in a system; based on the corresponding relation of each fuel cell, constructing a target function by taking maximization of the overall efficiency of the system as a target; and performing iterative optimization on the objective function according to the load power of the system to obtain the optimal output power required to be borne by each fuel cell. According to the method, part of units can be prevented from running in a low-efficiency interval for a long time, the overall efficiency of the system is remarkably improved, dynamic distribution is achieved through iterative optimization, the system automatically adapts to load changes, it is ensured that the system always runs at the optimal efficiency point, and the running cost is effectively reduced.