4372 results about "Dc converter" patented technology

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.

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.

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).

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.

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.

The present disclosure relates to circuits for connecting components of a hydrogen plant to a power grid to power the components in an efficient manner. In one implementation, power-side alternate current (AC) to direct current (DC) converters may be connected to a source power grid without the need for an isolation transformer by providing separate buses between the power-side AC-DC converters and load-side DC-DC converters instead of a shared DC bus between the converters. Other implementations for connecting components of a hydrogen plant to a power grid may include an adjustable transformer, such as a tappable transformer or an autotransformer, to connect any number of auxiliary loads of the plant to the power grid. The adjustable transformer may provide for various types of auxiliary load devices to connect to the power provided by the transformer at the same time, including both three-phase devices and one-phase devices.

A system comprises: a high voltage (HV) direct current (DC) to DC converter (HVDC) including: one or more transformers; a bridge driver connected to a primary side of the one or more transformers; and one or more bridge rectifiers connected to a secondary side of the one or more transformers, the one or more bridge rectifiers including one or more bridge rectifier switches; a low voltage (LV) DC to DC converter (LVDC) connected to the HVDC; and a boost converter including: an inductor connected to the one or more bridge rectifier switches; and one or more boost configuration switches operable, in combination with the one or more bridge rectifier switches, to configure the boost converter into each of a bypass configuration and a boost configuration, to regulate a voltage at the LVDC.

The invention relates to the technical field of fuel cell control, and discloses a control method of a hydrogen fuel system controller, which comprises the following steps: in response to a system shutdown instruction, controlling a DC / DC converter to maintain operation and request a preset scavenging current, and consuming residual reaction gas in a flow channel and a pipeline by using an electrochemical power generation reaction in an electric pile; meanwhile, hydrogen-cut air-down operation is executed, and the average single voltage of the electric pile is collected in real time; when it is monitored that the average monomer voltage is reduced to be below a preset anti-corrosion safety threshold value, the DC / DC converter is controlled to be disconnected, and mechanical purging is started. A time sequence interlocking mechanism of electrochemical energy depletion and mechanical purging is established, a high-potential retention path in the shutdown process is blocked from the physical and chemical source, and the safety of the shutdown is improved. Reverse polarity corrosion caused by a hydrogen-air interface effect is avoided, and the service life of the galvanic pile is prolonged.

The invention discloses a three-phase vehicle-mounted charger hierarchical control method and system based on a battery state, and the method comprises the steps: obtaining the battery state data of a vehicle-mounted power battery, the battery state data at least comprising a battery voltage and a battery charge state; determining a charging mode according to the battery voltage and / or the battery charge state; when the charging mode is a first charging mode, controlling the PFC converter to operate in a constant voltage output mode, and executing voltage following control on the bidirectional DC-DC converter based on the battery voltage; and when the charging mode is a second charging mode, executing voltage following control on the PFC converter based on the battery voltage, and controlling the bidirectional DC-DC converter to operate in a constant-frequency or constant-phase output mode at the same time. By setting hierarchical control strategies under different working conditions, the output voltage of the PFC converter is adaptively adjusted, the voltage regulation transformation ratio under different working conditions is optimized, the overall circuit structure is improved, and the charging efficiency of the vehicle-mounted charger within the full working condition range is improved.

The invention belongs to the technical field of power distribution, and discloses a direct current transformer soft switch and a control method.The direct current transformer soft switch comprises a medium-voltage direct current bus and low-voltage direct current buses, the medium-voltage direct current bus is electrically connected with a modular multi-level multi-port direct current converter, and the modular multi-level multi-port direct current converter is electrically connected with a plurality of low-voltage direct current converters; the plurality of low-voltage direct-current converters are electrically connected with a low-voltage direct-current bus and are used for realizing bidirectional power transmission from medium-voltage direct current to low-voltage direct current; according to the method, the medium-voltage side inductance value is reduced, the medium-voltage side current ripple is enabled to pass zero, the M3DC operates in an approximate critical conduction mode, a constant valley current control strategy is adopted, the minimum value of the medium-voltage side inductance current is controlled to be constant under different working conditions, and then zero-voltage switching-on of a switching device in a wide operation range and zero-current switching-off of an anti-parallel diode are achieved.

A current comparator includes: a first capacitor having a first end coupled to a first input signal; a second capacitor having a first end coupled to a second input signal; a first transistor having a control electrode coupled to the second end of the first capacitor; and a third transistor having a control electrode coupled to the second end of the second capacitor. The first current electrodes of the first and second transistors are coupled, and the second current electrodes of the first and second transistors are coupled to the first and second circuit nodes, respectively. A single-ended cascode amplifier has an input coupled to the second circuit node via a third capacitor. A set of auto-zero switches selectively shorts the control electrode of the first transistor and the second current electrode in response to an auto-zero control signal, and selectively shorts the control electrode of the second transistor and the second current electrode.

The invention discloses a power grid friendly light storage direct current integrated grid-connected control method and device. The method comprises the following steps: acquiring a power grid dispatching instruction, a common connection point voltage / frequency deviation, the maximum power of a photovoltaic unit, the charge state of an energy storage unit and a power limit value in real time; calculating a total active / reactive power target value required to be injected into the power grid by the grid-connected converter based on the power grid dispatching instruction and the common connection point voltage / frequency deviation; generating a photovoltaic power / energy storage power dynamic adjustment coefficient in real time according to the power grid frequency deviation amplitude, the voltage out-of-limit grade and the charge state of the energy storage unit, and decomposing the total active power target value into photovoltaic unit / energy storage unit instruction power; adjusting the direct-current bus voltage based on the total active / reactive power target value in a grid-connected converter control layer to realize a power grid supporting function; in a local unit control layer, photovoltaic unit instruction power is tracked through a photovoltaic unit DC / DC converter, and energy storage unit instruction power is tracked through an energy storage unit bidirectional DC / DC converter.

An electric vehicle charging system comprising a Direct Current (DC) distributor, a site controller, one or more alternating current (AC) / DC rectifiers connected to the DC distributor and the site controller, and an electric vehicle charger having one or more DC / DC converters connected to the DC distributor and a charge controller in communication with the site controller and each of the one or more DC / DC converters. The one or more AC / DC rectifiers are decoupled from the one or more DC / DC converters.

A DC / DC converter includes a converter stage to receive an input voltage and to provide an output voltage from the input voltage in accordance with a modulated drive signal. The converter stage further provides a feedback voltage representing the output voltage. A controller circuit includes an error amplifier to receive the feedback voltage and a reference voltage and to provide an error signal based on the feedback voltage and the reference voltage. A PWM modulator receives a clock signal and the error signal and generates a modulated signal based on the clock signal and the error signal, and a logic circuit receives the modulated signal and generates the drive signal for the converter stage based on the modulated signal so that the drive signal has the same duty cycle as the modulated signal, when the duty cycle of the modulated signal is not smaller than a minimum duty cycle value.

The invention provides an intelligent charging system and method based on illumination intensity adaptive adjustment. The intelligent charging system and method are applied to a photovoltaic energy storage system comprising a photovoltaic cell, a DC-DC converter, a storage battery charging mode control module and a storage battery. The method comprises the following steps: firstly, acquiring current illumination intensity, an incident light angle and a working environment temperature, and sending the current illumination intensity, the incident light angle and the working environment temperature to a photovoltaic cell and storage battery charging mode control module; the photovoltaic cell outputs corresponding voltage and current based on the parameters and a temperature compensation mechanism; and the storage battery charging mode control module converts the output of the photovoltaic battery into charging voltage and current for the storage battery, and dynamically determines a constant-voltage or constant-current charging mode in combination with the illumination intensity, the environment temperature, the incident light angle and the charging parameters, so that the self-adaptive charging of the storage battery is realized. Through multi-parameter cooperative adjustment, the charging mode is accurately matched with the environment condition and the storage battery state, and the charging efficiency and the system stability can be improved.

A cascoded power switch includes a high-side (HS) switch between an output node and a first voltage supply terminal and a low-side switch. The HS switch includes a first, second, and third transistor in series between the first voltage supply terminal and the output node, and a fourth, fifth, and sixth transistor in series between the first voltage supply terminal and the output node. The first and fourth transistors are in parallel, the second and fifth transistors are in parallel, and the third and sixth transistors are in parallel. A HS driver circuit begins turning on the first transistor in response to assertion of a first control signal and delays turning on the fourth transistor until both the first and second controls signal are asserted. A voltage monitoring circuit includes logic which asserts the second control signal in response to a rise of an output voltage at the output node.

An electronic device includes: a DC / DC converter including an inductor and a first switch and a second switch; and a control circuit operatively coupled to the DC / DC converter. An end of the first switch is connected to a power source, another end of the first switch is connected to an end of the second switch, and another end of the second switch is connected to ground. The control circuit: determines a peak value of current applied to the inductor from the end of the first switch; determines a valley value of the current applied to the inductor from the other end of the second switch; and controls the first switch and the second switch such that the peak value of the current applied to the inductor is not greater than a current value corresponding to a difference between the output voltage of the DC / DC converter and a reference voltage.

The invention discloses an isolated high-voltage direct-hanging energy storage converter and energy balance integrated control method. The method comprises the following steps: S1, acquiring SOC and voltage of each battery cluster in an energy storage converter; s2, establishing a controlled energy channel between the battery clusters, and performing self-balancing transfer on energy between the adjacent battery clusters according to voltage and SOC differences between the battery clusters; s3, selecting an expansion phase shift mode according to the power flow direction between the battery clusters, and selecting a phase shift ratio under the constraint of transmission power to reduce current stress and backflow power; s4, generating a modulation coefficient of a shared bridge arm according to decoupling inductive current inner loop proportion tracking; performing PR current closed loop on the main bridge arm, and generating a switching sequence of each switching tube of the shared bridge arm by adopting unipolar carrier phase-shifting modulation; and S5, outputting the modulation coefficient of the shared bridge arm and the switching sequence of each switching tube, driving the isolated bidirectional DC-DC converter and each H-bridge module to work, and realizing grid-connected energy bidirectional flow and voltage and current index satisfaction.

A power converter (100) for converting multi-phase AC grid input power (GIV, GIC) to DC output power. For allowing efficient, cost-effective, easy installable, and reliable power supply to a DC power consumer with high power requirements, it includes at least one phase block (106A, 106B), each having at least two separate converter single-phase string arrangements (1), each of them including an individual active rectifier portion (10), including a H-bridge with semiconductor switches (12), for rectifying single-phase AC input power (SInV, SInC) to intermediate DC power and an individual DC / DC converter (20). The latter includes an inverter portion (30), having a H-bridge with semiconductor switches (32), for inverting the intermediate DC power to first intermediate AC power (PAC1) with an elevated frequency (f1), a transformer (40, 240) for transforming the first intermediate AC power (PAC1) to second intermediate AC power (PAC2, PAC2A, PAC2B), and a passive diode rectifier (50, 150, 250), including a diode bridge (51), for rectifying the second intermediate AC power (PAC2, PAC2A, PAC2B). The disclosure further discloses a hydrogen production facility (200) with an electrolyzer stack (20) and such a power converter (100).

A method and circuit for controlling a bidirectional resonant direct-current converter are provided. The method includes obtaining an input and / or output electrical parameter of the converter; determining respective delay time periods of bridge arms in the secondary circuit based on the input and / or output electrical parameter and a desired gain of the converter; determining a switching frequency to be greater than a resonant frequency of the resonant tank based on the input and / or output electrical parameter and a preset reference signal; and turning off, in response to a secondary resonant current of the converter reaching zero, corresponding switching transistors of the switching transistors in the secondary circuit immediately after the respective delay time periods starting from a zero-crossing point; and turning on other switching transistors complementary to the turned-off switching transistors in the secondary circuit immediately after a dead time.

The invention belongs to the technical field of storage and charging equipment, and particularly relates to a storage and charging all-in-one machine which comprises a shell cooling mechanism, the interior of a shell is divided into a battery bin and an inversion bin, a battery module is arranged in the battery bin and comprises a plurality of stacked battery cells, an alternating-current and direct-current inverter is arranged in the inversion bin, and the battery cells are connected with the alternating-current and direct-current inverter. And the AC / DC inverter is electrically connected with the battery module. According to the invention, a closed-loop liquid cooling circulation system is adopted, heat conduction liquid can rapidly take away heat when the battery cell works, performance degradation or potential safety hazards of the battery cell caused by too high temperature are avoided, the heat dissipation area is increased through the design of the circuitous and surrounding insulating heat conduction pipe, and the cooling efficiency is obviously higher than that of a traditional air cooling scheme in cooperation with constant temperature control of the industrial water cooler. The shell is divided into the battery bin and the inverter bin, the battery module and the alternating current and direct current inverter are arranged in a partitioned mode, mutual interference of heat generated when the battery and the inverter work can be properly avoided, maintenance of all parts is facilitated, and the operation stability of equipment is improved.

The present disclosure relates to a standby power supply, including: a first sub power supply configured to provide alternating current electrical energy, where the first sub power supply is connected to an input terminal of an alternating current / direct current (AC / DC) converter; the AC / DC converter configured to convert the alternating current electrical energy into direct current electrical energy, where an output terminal of the AC / DC converter is connected to an output terminal of the standby power supply; and second sub power supplies configured to provide the direct current electrical energy, where the second sub power supplies are connected to the output terminal of the standby power supply. Through the present disclosure, a standby power supply solution having high reliability and capable of meeting power consuming requirements of a load with a great change in power demand such as a wind generator may be provided.

The invention relates to an electric engine, a power device and an aircraft, and belongs to the technical field of aircraft power equipment.The electric engine comprises a power motor and a liquid cooling flow path arranged in the power motor and comprises a stator support; the heat dissipation system comprises a fan, a radiator and a heat dissipation motor, an outlet of the radiator is connected with an inlet of the liquid cooling flow path, an inlet of the radiator is communicated with an outlet of the liquid cooling flow path, and the fan is used for cooling the radiator and / or the power motor; the motor rear cover is fixedly connected with the stator bracket; and the two direct-current converters are both mounted on the motor rear cover and are both electrically connected with the heat dissipation motor. The two direct-current converters convert high-voltage direct current accessed by the electric engine into low-voltage direct current capable of being used by the heat dissipation motor, and the electricity utilization requirement of the heat dissipation motor is met. Due to the redundancy design of the two direct-current converters, when one path of low-voltage power supply breaks down, the other path of low-voltage power supply can still supply power to the heat dissipation motor in a low-voltage mode, and enough fault handling time can be provided for the whole power supply system.

A bidirectional high voltage AC-DC converter includes a primary three-phase three-level T-type power factor correction circuit, a full-bridge switching circuit connected to the primary three-phase three-level T-type power factor correction circuit output, an isolated capacitor-inductor-inductor-capacitor (CLLC) resonant tank connected to the full-bridge switching circuit, a T-type full-bridge output topology circuit connected to the CLLC resonant circuit, and a controller that controls one or more of the components of the bidirectional isolated high voltage AC-DC converter. The primary three-phase three-level T-type power factor correction circuit and the secondary three-level circuit include a split DC-link bus with respective voltages that are actively controlled by the controller. The CLLC resonant converter circuit includes an isolation transformer that electrically isolates the primary side from the secondary side of the bidirectional isolated high voltage AC-DC converter. A control method includes synthesizing, via a modified space vector pulse width modulation (SVPWM) scheme or a variable-amplitude double-carrier sine-triangle PWM with capacitor bank middle point voltage control, one or more output voltages of the front end three-phase three-level T-type PFC circuit, wherein the modified SVPWM scheme is based, at least in part on a nearest four vectors technique.

Systems and methods for supplying power (both active and reactive) at a medium voltage from a DCSTATCOM to an IT load without using a transformer are disclosed. The DCSTATCOM includes an energy storage device, a two-stage DC-DC converter, and a multi-level inverter, each of which are electrically coupled to a common negative bus. The DC-DC converter may include two stages in a bidirectional configuration. One stage of the DC-DC converter uses a flying capacitor topology. The voltages across the capacitors of the flying capacitor topology are balanced and switching losses are minimized by fixed duty cycle operation. The DC-DC converter generates a high DC voltage from a low or high voltage energy storage device such as batteries and / or ultra-capacitors. The multi-level, neutral point, diode-clamped inverter converts the high DC voltage into a medium AC voltage using a space vector pulse width modulation (SVPWM) technique.

The invention discloses a distributed light storage and charging integrated system, which comprises a photovoltaic power generation unit, an energy storage unit, a charging unit, a power grid interface unit, an energy management controller and a direct current bus, the photovoltaic power generation unit comprises a DC / DC converter, and the photovoltaic power generation unit is connected with the DC bus through the DC / DC converter; the energy storage unit comprises a lithium ion battery pack, a flywheel energy storage device, a bidirectional DC converter and a flywheel controller. The lithium ion battery pack and the flywheel energy storage device are connected to the DC bus through the bidirectional DC converter and the flywheel controller respectively. The charging unit comprises at least one direct-current quick charging pile, at least one alternating-current slow charging pile and a DC / AC inverter, the direct-current quick charging pile is directly connected with the direct-current bus, and the alternating-current slow charging pile is connected with the direct-current bus through the DC / AC inverter; the power grid interface unit comprises an AC / DC converter and is connected with the DC bus through the AC / DC converter. According to the invention, through collaborative design of a modular hardware architecture and an intelligent time-sharing strategy, comprehensive improvement of economy, reliability and functionality of the system is realized.

An onboard charging system for an electric vehicle includes a charging port configured to receive a single-phase AC power, a power outlet configured to provide the single-phase AC power to one or more external devices, a single-phase inverter connected to the power outlet and configured to provide power splitting functionality, a DC battery selectively coupled to the charging port, a bidirectional inverter configured to convert AC power to DC power and to convert DC power to AC power, the bidirectional inverter is selectively coupled to the battery, an electric motor coupled to the bidirectional inverter and selectively coupled to the charging port, a DC-AC converter selectively coupled to the electric motor and selectively coupled to the power outlet, and a DC-DC converter coupled to the DC-AC converter and selectively coupled to the battery.

The invention provides a DC Buck converter voltage and current sensor fault-tolerant control system, which comprises the following steps: establishing a time-varying state space model of a DC Buck converter, and dynamically reconstructing a parameter matrix by the time-varying state space model according to the real-time change of a duty ratio; the time-varying augmentation fault estimator is used for monitoring faults of a voltage sensor and a current sensor in real time, the fault estimator is implemented through a model reference adaptive filter, a Buck converter is adopted to construct a reference model in a healthy state, and efficient real-time diagnosis and correction can be achieved through the faults of the voltage sensor and the current sensor of the Buck converter. And various types of sensor faults such as a jump fault, an offset fault, a stuck fault, a high-frequency fault and a gap fault can be effectively estimated. For measurement distortion of the voltage sensor and the current sensor, the fault estimator can provide comprehensive evaluation information of fault types and fault severity.