6013 results about "Dc converter" patented technology

A tracking and adaptive compensation method for power fluctuation of a pulse load of a ship is provided. The method includes: based on a microgrid topology model of the ship, a pulse load model of the pulse load, and an interharmonic power and pulse parameter relationship model, performing power fluctuation tracking, frequency selection and a power spectrum analysis to obtain filtering parameters of a low-pass filter and filtering parameters of a band-pass filter; performing waveform adaptation to eliminate a phase delay caused by the low-pass filter and the band-pass filter, and obtaining a control command for a power compensation strategy; and generating, by a power loop, a pulse width modulation (PWM) signal to control a switching tube in a bidirectional direct current (DC) / DC converter of each of an energy storage battery pack and a supercapacitor of a hybrid energy storage system.

The invention provides an intelligent temperature field analysis-based heat dissipation optimization method for an IGBT (Insulated Gate Bipolar Translator) power module of an offshore flexible direct current converter valve. According to the method, an IGBT module space temperature data matrix and multi-point temperature sensor data are collected, and filtering processing is carried out through a multi-scale sliding window and a self-adaptive threshold value; establishing a multi-layer thermal network parameter model, and analyzing temperature dynamic change characteristics; layering the feature data according to the thermal response speed, and performing adaptive mapping and weight calculation; establishing a reinforcement learning model based on the heat dissipation efficiency index set to optimize a heat dissipation strategy; and predicting the temperature field distribution by using the graph structure neural network model. Accurate sensing, dynamic characteristic analysis, self-adaptive control and predictive maintenance of the temperature field of the IGBT module are realized, the heat dissipation efficiency and the temperature uniformity are improved, and the service life of equipment is prolonged.

The invention relates to the technical field of battery management, and discloses an equalizing charging method, device and equipment for a power battery pack. The method comprises the following steps: performing parameter acquisition on a power battery pack, measuring terminal voltage values, temperature values and charge and discharge current values of each single battery, and calculating a state-of-charge value and an internal resistance change rate of each single battery; inputting into a multi-head self-attention network for feature extraction, and generating a state correlation feature matrix; constructing an Actor network and a Critic network based on the state correlation characteristic matrix, and outputting an equalization current value, a constant-current or constant-voltage equalization mode and equalization time through the Actor network; according to the equalization current value, the equalization mode and the equalization time, the DC-DC converter in the main equalization loop is controlled to generate constant current output, or the Buck-Boost converter in the secondary equalization loop is controlled to generate constant voltage output, the equalization efficiency of the power battery pack is guaranteed, meanwhile, energy loss is reduced, and temperature self-adaptive control over the equalization circuit is achieved.

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 an intelligent scheduling control method, system and device of an optical storage hybrid inverter, and a medium, and belongs to the technical field of new energy power systems.The method comprises the steps that a scheduling controller collects the output power of a photovoltaic battery, the electric quantity state of an energy storage battery, the power grid electricity price and the load power; generating a photovoltaic power prediction value and a load prediction value by using the prediction model; solving an optimal power distribution scheme by taking economy optimization as a target to obtain photovoltaic side target power, energy storage side target power and power grid interaction target power; the duty ratio of the photovoltaic side bidirectional DC / DC converter is adjusted according to the photovoltaic side target power to achieve maximum power point tracking of the photovoltaic cell, the duty ratio of the energy storage side bidirectional DC / DC converter is adjusted according to the energy storage side target power to achieve charging and discharging power control of the energy storage cell, and the output current of the grid-connected inverter is adjusted according to the power grid interaction target power. According to the invention, efficient and intelligent control of the optical storage hybrid inverter can be realized.

A system includes: an AC-DC converter; and a DC-DC converter, the DC-DC converter including: a first high voltage buck-boost converter having a secondary side connectable to a first high voltage battery; a second high voltage buck-boost converter having a secondary side connectable to a second high voltage battery; a first low voltage buck-boost converter having a secondary side connectable to a first low voltage battery; a second low voltage buck-boost converter having a secondary side connectable to a second low voltage battery; and one or more transformers having a primary side connected to the AC-DC converter and a secondary side connected to each of a primary side of the first high voltage buck-boost converter, a primary side of the second high voltage buck-boost converter, a primary side of the first low voltage buck-boost converter, and a primary side of the second low voltage buck-boost converter.

The invention discloses an output conversion system and method for a UPS (Uninterrupted Power Supply), and the system comprises a main power input end which is connected with a bridge rectifier through a first electromagnetic relay; the energy storage module comprises a super capacitor group and a parallel lithium battery group, and is coupled with the bus capacitor through a bidirectional DC / DC converter; the input end of the multi-path regulation and control module is connected with the bus voltage sensor, and the output end is connected with the switching execution unit through a second electromagnetic relay group; the dynamic switching unit comprises an I-GBT matrix and a reverse blocking diode array which are respectively connected with the inverter and the bypass circuit in parallel; and the real-time monitoring module is provided with a current harmonic analysis unit and a load break variable detection unit, and the output end of the real-time monitoring module is connected with the ADC port of the central processor. According to the invention, systematic improvement is realized in three dimensions of electric energy quality guarantee, equipment reliability and dynamic response capability through an original multi-path regulation and control architecture and a deep cooperative intelligent control strategy.

The invention relates to an MPPT (Maximum Power Point Tracking) control method based on dynamic optimization of a lightweight convolutional neural network, and belongs to the field of artificial intelligence control power tracking. The method comprises the following steps: S0, constructing a convolution-fuzzy neural network model which at least comprises an input layer, a convolution layer, a fuzzy control layer, a deep reinforcement learning layer and an output layer; s1, key parameters of photovoltaic equipment are collected in real time to serve as input data of an input layer; s2, performing convolution operation on the input data by using a convolution layer, extracting a feature vector, and transmitting the feature vector to a fuzzy control layer; s3, combining a fuzzy control layer with a deep reinforcement learning layer, and dynamically adjusting an optimization process of a fuzzy rule through a reward signal; and S4, the fuzzy control layer generates a control signal, and the control signal is transmitted to a DC / DC converter of the photovoltaic system through the output layer. The control method is suitable for a dynamic environment of a photovoltaic power generation system, can be expanded to a grid-connected system, and provides a new thought and technical support for efficient operation of photovoltaic power generation.

The invention discloses a photovoltaic hydrogen production power supply topological structure based on MPPT and a control method, and relates to the technical field of renewable energy electrolysis hydrogen production, and the photovoltaic hydrogen production power supply topological structure mainly comprises a photovoltaic power module, a direct current bus, a water electrolysis hydrogen production unit, an energy storage unit and a control unit. The photovoltaic power modules are connected in parallel to the direct current bus through the independent DC / DC converter, and are matched with the automatic identification and scheduling functions of the control unit, the system operation strategy is automatically adjusted when the modules are newly added or faults exit, and plug-and-play, fault isolation and power reconstruction of the photovoltaic power modules can be supported; the duty ratio change step length of the DC / DC converter is limited when the current rapidly fluctuates due to the change of the photovoltaic output power, the current change rate of the electrolytic cell stack is effectively controlled, the service life protection of the electrolytic cell can be considered, the high modular access capability is achieved, multi-source collaborative scheduling is supported, and bus voltage stabilization and system current sharing optimization can be achieved.

A simulation system of a railway system for a Medium-Voltage Direct Current (MVDC) distribution network includes: a computing device which stores a simulation program including a converter station model configured to simulate a converter station included in the MVDC distribution network and a train operation model configured to simulate an operation state of a train that is supplied with power from the converter station and runs; a converter controller which controls a DC / DC converter included in the converter station model; and a Hardware In the Loop Simulation (HILS) device which performs a simulation based on the converter station model, the train operation model, and the converter controller. Herein, the converter station model and the train operation model are executed in software by the HILS device, and the converter controller is connected to the HILS device and driven to control the converter station model.

Presented are high-voltage (HV) electrical system architectures for vehicle-to-vehicle (V2V) charging of vehicle batteries, methods for making / using such systems, and vehicles equipped with such systems. An HV electrical system for a motor vehicle includes a main HV bus that electrically connects the vehicle's traction motor(s) to the vehicle's battery pack(s), and a charging inlet port that electrically mates with and receives direct-current (DC) power from DC fast-charging (DCFC) cables of a donor vehicle and a charging station. A DC-to-DC (DC-DC) converter is interposed between and electrically connects the charging inlet port to the main HV bus. The DC-DC converter is operable in a bypass mode, in which the DC-DC converter passes therethrough DC power received from the DCFC cable of the charging station, and a vehicle-to-vehicle (V2V) mode, in which the DC-DC converter modulates DC power received from the DCFC cable of the donor vehicle.

The invention provides an open-circuit fault diagnosis method for a three-phase interleaving three-level DC-DC converter, which comprises the following steps of: establishing a mathematical model of the three-phase interleaving three-level DC-DC converter by taking the sum of three-phase inductive current iL1 + iL4, iL2 + iL5 and iL3 + iL6 of inductive current iL1-iL6 of the three-phase interleaving three-level DC-DC converter as state variables; on the basis, designing an improved sliding-mode observer of the three-phase interleaving three-level DC-DC converter, and combining an observation value output by the improved sliding-mode observer with an actual value of the sum of inductive currents of upper and lower bridge arms of the same phase to construct a fault detection variable Mx (x = A, B and C) based on a residual gamma (t); a fault detection variable Nj based on the difference value between the inductive current iL1-iL6 and the current mean value is constructed by utilizing the characteristic that the corresponding inductive current declines at the fastest speed after the open-circuit fault of the switching tube, and j is equal to 1-6; and judging whether the corresponding switch tube has an open-circuit fault or not by comparing the two fault detection variables with a set threshold value.

The invention discloses a low-cost high reactive overload energy storage converter topology and a modulation strategy thereof, is used for improving the reactive overload capacity of an energy storage converter, and belongs to the technical field of alternating current-direct current converters. According to the invention, the auxiliary diode is additionally arranged on the traditional ANPC bridge arm, so that the reverse current of the IGBT module is shared during high-proportion reactive output of the converter, and the reactive overload capacity of the converter can be efficiently improved with low cost on the basis of fully utilizing the existing equipment. Besides, a reactive overload capacity enhancement modulation strategy based on third harmonic injection is provided for the topology, and third harmonics are injected into modulation waves, so that the utilization rate of an auxiliary diode is improved, and the output capacity of reactive current is further enhanced. According to the method, a 100kVA prototype is tested and verified in Simulink / Plecs, the device cost of the proposed topology is only increased by 5.45% on the basis of a traditional ANPC, the reactive overload capacity is increased by 22%, and the power grid voltage supporting capacity of the energy storage converter can be effectively enhanced.

A system includes: an alternating current (AC) to direct current (DC) converter (AC-DC converter), the AC-DC converter connectable to a line voltage; and a DC to DC converter (DC-DC converter) connected to the AC-DC converter, the DC-DC converter including: a high voltage buck-boost converter having a secondary side connectable to a high voltage battery; a low voltage buck-boost converter having a secondary side connectable to a low voltage battery; and one or more transformers having a primary side connected to the AC-DC converter, a secondary side connected to a primary side of the high voltage buck-boost converter, and a tertiary side connected to a primary side of the low voltage buck-boost converter.

There is provided a vehicle control device including: an inverter that is configured to drive an electric motor; a DC / DC converter that is configured to step down a voltage output from a high voltage battery; a pre-charge circuit including a pre-charge switch; a voltage detector that is configured to detect an input voltage input to the inverter and the DC / DC converter; and a controller. When the input voltage is lower than the input voltage at the time when pre-charge of the inverter is completed, the controller is configured to determine that power supplied from a power supply of the DC / DC converter to the DC / DC converter is not normally stopped.

The invention relates to the technical field of power systems, and discloses a broadband oscillation risk assessment method and system for offshore wind power through a flexible direct current sending-out system, and the method comprises the steps: dividing a broadband oscillation risk assessment frequency band into a medium-high frequency band and a sub-super-synchronous frequency band; aiming at different broadband oscillation risk assessment frequency bands, respectively establishing an offshore wind power plant side impedance model and a flexible direct current converter side impedance model in a corresponding offshore wind power flexible direct current sending-out system, and determining an equivalent impedance frequency characteristic curve of the offshore wind power plant side and the flexible direct current converter side. The broadband oscillation risk of the offshore wind power through the flexible direct current sending-out system is comprehensively evaluated by using the equivalent impedance frequency characteristic curve, the topological structure and the operation condition are fully considered, and the accuracy and adaptability of evaluation are improved. And when the broadband oscillation risk occurs, the system is adjusted in a targeted manner according to different evaluation frequency bands, so that the broadband oscillation risk is effectively eliminated, and the operation stability of the offshore wind power output system through the flexible direct current is enhanced.

The invention discloses a wide-temperature-range sodium-lithium hybrid energy storage system and a control method thereof. According to the system, the working temperature range of the energy storage system is effectively expanded through sodium-lithium hybrid energy storage; the sodium ion battery unit bears a low-temperature working condition, and the lithium ion battery unit bears a normal-temperature basic load, so that the low-temperature and power characteristics of a sodium battery and the high-energy density advantage of a lithium battery are exerted, and complementation of energy density and temperature adaptability is realized; and the independent bidirectional DC / DC converter is adopted for power coupling, so that the problem of voltage mismatching possibly caused by direct parallel connection is effectively avoided, and the reliability and the control precision of the system are improved. The system has intelligent environment perception and adaptive control capabilities, can adaptively adjust a working mode and a power distribution strategy according to environment conditions, and is high in intelligent degree. The modular design is adopted, system expansion and maintenance are facilitated, and the operation and maintenance cost is reduced.

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

A power-over-Ethernet (PoE) PD / PSE device comprises a powered device (PD) interface configured to connect to an upstream power sourcing equipment (PSE) and receive input PoE power from the PSE, and a PSE interface configured to connect to a downstream PD and to supply output PoE power to the PD. The PD / PSE also comprises a device power rail to supply operational power to one or more components of the PD / PSE, and a DC-DC converter comprising a multi-output transformer comprising a transformer input, a first transformer output electrically connected to the PSE interface, and a second transformer output electrically connected to the device power rail. The DC-DC converter is configured to receive the input PoE power and, in response, supply the input PoE power to the transformer input, generate the output PoE power at the first transformer output, and generate the operational power at the second transformer output.

The invention relates to an on-board electrical system (1) for a vehicle, comprising a high-voltage on-board electrical system (2) with a high-voltage battery (HVB) and a low-voltage area with an on-board electrical system channel (EBN) which is designed as a comfort on-board electrical system (EBN), wherein the comfort on-board electrical system (EBN) is connected to the high-voltage on-board electrical system (2) via a DC / DC converter (DCDC2) and is configured to supply static loads (L1), wherein a low-voltage battery (LVB1) is arranged in the comfort on-board electrical system (EBN), wherein the on-board electrical system (1) is designed to be expandable by means of further on-board electrical system channels (SBN1, SBN2).

A soft start circuit of a synchronous boost DC-DC converter is used for restraining current overshoot and voltage overshoot of the synchronous boost DC-DC converter in the starting process and comprises a first soft start module and a second soft start module. The first soft start module belongs to system open-loop work, and suppresses a channel length modulation effect through the same drain end voltage of a clamping matching tube and a power upper tube, so as to obtain a precisely controlled charging current. A second soft start module belongs to system closed-loop work, and the method comprises the following steps: in the first stage, VOUT partial voltage is synchronized; in the second stage, constant-current charging is carried out; and in the third stage, the error amplifier vref rises gently through preset voltage RC charging. According to the invention, current overshoot and voltage overshoot are effectively suppressed through two soft start stages, and the starting circuit has a wide application prospect in the field of starting circuits.

The present invention provides a battery energy storage parallel equalization converter topology and a control method therefor. The battery energy storage parallel equalization converter topology comprises a series-connected battery energy storage parallel equalization converter, a main converter, and a plurality of groups of filter inductors; in the main converter, the input side of a DC / DC or DC / AC converter is connected in parallel to a parallel voltage-stabilizing capacitor, and the output side of the DC / AC or DC / AC converter is correspondingly connected to an AC or DC source load; the series-connected battery energy storage parallel equalization converter comprises a plurality of groups of small-capacity DC / DC converters and a common DC bus capacitor; the output sides of all the small-capacity DC / DC converters are connected in parallel by means of the common DC bus capacitor to form a common DC bus; the input side of one group of small-capacity DC / DC converters is connected in series to the input side of the main converter, and the input sides of other groups of small-capacity DC / DC converters are connected in series to a battery pack by means of the filter inductors, respectively. According to the present invention, in a battery charging and discharging process, only a small amount of power flows through the converter, reducing the capacity requirements of the converter, and reducing the transmission efficiency.

A fault tolerance method based on a seabed medium-voltage direct-current converter, and a redundant topological structure are provided. The method controls and adjusts working states of resonant conversion modules and switch states of redundant switching structures connected to the resonant conversion modules, to supply power to a load; and in the process of supplying power to the load, obtains fault diagnosis results for the resonant conversion modules. Based on the fault diagnosis results, that a faulty module exists in the resonant conversion modules, the faulty module is removed. After the faulty module is removed, a redundant resonant conversion module is determined, and the working state of the redundant resonant conversion module and the switch state of the redundant switching structure connected to the redundant resonant conversion module are adjusted, wherein the redundant resonant conversion module is configured to replace the faulty module.

An electric work vehicle includes a body, a travel device in the body, a motor to drive the travel device, an inverter to supply power to the motor, an electric component, a DC / DC converter to convert a voltage of power to be supplied to the electric component, a radiator to cool coolant, and a cooling path through which the coolant cooled by the radiator circulates through the motor, the inverter, and the DC / DC converter and returns to the radiator. The cooling path extends from the radiator, passes through the inverter, the motor, and the DC / DC converter in this order, and returns to the radiator.

The invention provides an EIS on-line detection system and method for a high-power fuel cell system, a main loop of the EIS on-line detection system adopts two Boost type converter topological structures which are connected in parallel, and small signal excitation injection is carried out through an auxiliary DC / DC converter 2; the control system comprises a sampling system, a PWM drive circuit, a communication module and an embedded controller. Establishing a battery equivalent circuit model; when a high-power fuel cell system runs, a multi-frequency sine periodic signal optimized by a non-dominated sorting genetic algorithm improved based on Tent chaotic mapping is injected into an output current of an auxiliary DC / DC converter 2; sampling the voltage of a single body or a galvanic pile, measuring current data, calculating the voltage drop corresponding to the internal resistance of the current data, converting a time domain signal into a frequency domain signal, and obtaining the battery impedance information in the corrected Foouquet equivalent circuit model; importing the characteristic parameter data into a least square support vector machine (LSSVM) for training and testing, and performing in-situ detection and fault diagnosis on line; according to the invention, a new way can be provided for active diagnosis and early warning of faults.

The invention discloses a general transient DC bias suppression method for a dual-active-bridge converter under bidirectional power flow. The method comprises the following steps: when the dual-active-bridge DC converter operates stably, asynchronous carriers are generated; a certain modulation and control strategy is adopted, closed-loop operation is carried out in each switching period, and a primary side inner shift phase ratio D1, a secondary side inner shift phase ratio D2 and an outer shift phase ratio Df are generated; different working modes are selected according to the positive and negative relation of the external shift comparison between the current switching period and the previous switching period, and an asynchronously updated modulation wave is generated; and according to the selected working mode, determining a lead and lag relationship of the modulation wave, comparing the modulation wave with the carrier wave, and generating a driving signal of a power switch of the dual-active bridge converter. According to the method, the problem that an existing transient direct current bias suppression method is only suitable for a specific power flow direction or a specific modulation strategy can be solved, transient direct current bias suppression under power bidirectional flow is achieved, and safe operation of the dual active bridge converter is guaranteed.

The present invention relates to a new energy ship battery power control method and a system. Each battery pack correspondingly supplies power to one bus, one bidirectional DC-DC converter is arranged between two adjacent buses to form a bus loop, and a load correspondingly draws electrical power from a corresponding bus loop segment; a power supply state of each bus area is checked, and by controlling the bidirectional DC-DC converter between buses, surplus energy of one bus is distributed to another bus having insufficient energy. According to the solution, a low DC-DC capacity configuration is achieved, energy between battery packs can be flexibly scheduled, the remaining electrical power between battery packs can be effectively balanced, the system risk is low and controllable when a bus is short-circuited, the power performance of a ship is not reduced when a single point of failure occurs, and the reliability and safety of the ship are effectively improved.

An electric vehicle may be equipped with a swappable battery, and a power source management method. The electric vehicle includes a motor, an inverter configured to exchange three-phase power with the motor, a main battery unit which may be electrically connected to the inverter, includes a first battery and a first BMS for controlling the first battery, and may be fixedly disposed in the electric vehicle, an OBC which may be connected between the main battery unit and the inverter and includes a DC converter, and a switch unit configured to selectively connect a connector and the DC converter to each other, or the connector and the motor to each other, in which, when a swappable battery unit including a second battery and a second BMS for controlling the second battery may be connected to the connector, the first BMS acquires second-battery information output by the second BMS.

An EV charger has an AC-DC converter coupled to two DC-DC converters can be configured with V2V charging capability, together with a wide range of input / output voltages for accepting existing electric vehicle available on the market. The charger can include a variable transformer to partition the output voltage range into multiple subranges. In addition, the switching frequency of the DC-DC converter can be doubled when the voltage gain of the DC-DC converter deviates significantly from unity.

The present invention provides a topology, method and system for bi-directional power conversion of excitation power supply for power battery testing, wherein the topology comprises a three-phase PWM (pulse width modulation) converter, a high-frequency isolation three-level LLC (logical link control) resonant converter and a DC-DC (direct current) converter forming a topology structure for a three-stage power conversion; an input end of the three-phase PWM converter is connected to a power grid side; the high-frequency isolation three-level LLC resonant converter is connected between the three-phase PWM converter and the DC-DC converter in series and is configured for realizing bi-directional DC voltage conversion and isolation, and to raise a busbar voltage between the high-frequency isolation three-level LLC resonant converter and the DC-DC converter; and, the DC-DC converter is configured to generate charging and discharging excitation currents for a power battery testing.