41 results about "Active front end" patented technology

The invention discloses a domestic high-power IGBT rectification system and method, and relates to the technical field of IGBT rectification, and the method comprises the steps: constructing an active front-end rectification main circuit; a direct current side hybrid harmonic modulation auxiliary circuit is integrated; performing multiple delay signal elimination operation on the sampled signal, filtering out a harmonic interference signal, and locking the frequency and phase of the fundamental voltage of the power grid through a phase-locked loop; establishing a control structure of a voltage outer loop and a current inner loop, generating an instruction amplitude of a grid-side active current and an ideal sinusoidal current reference waveform, and controlling an IGBT in an active front-end rectification main circuit in real time; real-time fast Fourier transform analysis is carried out on the actual input current of the grid side, and residual harmonic components are identified; and feedback management of regenerated energy is realized. The invention provides a fused high-adaptability active front-end IGBT (Insulated Gate Bipolar Translator) rectification method and system which can stably operate under the condition of power grid voltage distortion and realize deep harmonic suppression and efficient energy bidirectional flow.

The invention relates to the technical field of DC bus anti-interference, in particular to an anti-interference control method and system for a DC bus. The DC bus anti-interference control method comprises the following steps: acquiring a first three-phase current actual value, a DC voltage reference value, a DC voltage actual value and a DC current actual value; determining a second three-phase current actual value corresponding to the first three-phase current actual value; determining a target current reference value according to the direct-current voltage reference value and the direct-current voltage actual value; determining a target disturbance parameter according to the DC voltage actual value and the DC current actual value; based on the second three-phase current actual value, the target current reference value, the target disturbance parameter, the target current reference value and the target disturbance parameter, calculating a value function corresponding to each switch state of the active front end; the active front end has eight different switching states; determining the switching state corresponding to the minimum value function as a target switching state; and controlling the switching state of the active front end based on the target switching state. And the anti-interference capability of the direct-current bus is improved.

The invention provides an alternating current charging and discharging system of a vehicle and an alternating current charging and discharging control method. The system comprises a plurality of first windings of a first motor of an electric drive system, a plurality of first inverters of the electric drive system, a direct current bus, an active front end rectifier and a controller. The first windings are correspondingly connected with the first inverters respectively; the plurality of first inverters are connected in parallel to the direct-current bus, and a first isolating switch is arranged on the direct-current bus between two adjacent first inverters; one end of the direct-current bus is connected to a battery of the vehicle, and the other end of the direct-current bus is connected to the active front-end rectifier; the controller is configured to control opening and closing of the first isolation switch, when the first isolation switch is controlled to be closed, the first motor outputs torque, when the first isolation switch is controlled to be disconnected, the multiple first windings and the multiple first inverters achieve DC / DC energy transmission and electrical insulation isolation of alternating current charging and discharging, and after the first isolation switch is controlled to be disconnected, the multiple second windings and the multiple first inverters achieve DC / DC energy transmission and electrical insulation isolation of alternating current charging and discharging. And controlling the bridge arm end of the first inverter to generate high-frequency pulse voltage.

The invention discloses a power recovery type tester for a high-pressure large-flow fuel pump, belongs to the technical field of aero-engine fuel pump tests, and solves the problem of large energy loss caused by the fact that redundant power of a tester is converted into heat dissipation. According to the technical scheme, the device mainly comprises a hydraulic motor, a generator, a safety overflow valve, an oil tank assembly and a refrigerating unit, one end of the oil tank assembly is connected with the refrigerating unit, the other end of the oil tank assembly is connected with a low-pressure oil supply pump, the low-pressure oil supply pump is connected with a tested piece, and one end of the tested piece is externally connected with a driving motor. One end of the control system is connected with a power supply system, the other end of the control system is connected with a safety overflow valve and a hydraulic motor, the hydraulic motor is connected with a generator, the generator is connected with an SMM converter system and an AEF active front end, the SMM converter system and the AEF active front end are matched to control a load system, and the generator is connected with a refrigerating unit. The invention is mainly used for reducing the energy dissipation and the installed power of the system.

The invention discloses an active front-end converter and a resonance suppression method thereof, and the active front-end converter comprises a rectifier circuit which is used for converting the AC electric energy of a power grid into DC electric energy and outputting the DC electric energy; the control module is connected with the rectifier circuit and is used for controlling the output current of the rectifier circuit; the filter circuit comprises an inductor unit and a capacitor unit, the capacitor unit comprises a filter capacitor and a split capacitor, the inductor unit is connected between the power grid and the input end of the rectifier circuit, one end of the filter capacitor is connected to the inductor unit, the other end of the filter capacitor is grounded, and the split capacitor is connected to the two ends of the filter capacitor in parallel. According to the active front-end converter, the loss can be reduced while resonance can be effectively suppressed, and the overall efficiency of the converter is higher.

A portable power supply may include an internal power source and a active front-end converter connected to the internal power source. The active front-end converter includes a positive DC connector lead, a negative DC connector lead, a positive source side lead, a negative source side lead, and a plurality of switches. The active front-end converter is configured to operate as a DC-DC converter for DC input signals and an AC-DC inverter for AC input signals. The portable power supply also includes an AC source input, and a DC source input.

Techniques to reduce discontinuities in power, for example, by controlling an electrical power output of an active front end unit during a transition between a first operating mode and a second operating mode. In some examples, to reduce discontinuities, a control unit of the active front end unit can seed the integrator of proportional-integral (PI) controllers that are brought online during the operating mode change with a value that represents the proper state of the current system, such as the measured or calculated value of the component the PI controller is controlling). In other examples, to reduce discontinuities, a control unit of the active front end unit can control reference frame alignment during a transition between a first operating mode and a second operating mode.

A variable speed drive motor system 10 comprises a variable speed drive motor 15, and an active front end (AFE) 14 for driving the variable speed motor, in which the AFE is configured to vary a DC lin

A solid-state transformer system comprises a plurality of isolated DC-DC converter modules, each module having a medium voltage port and a low voltage port. The medium voltage ports are series-connected in each phase of a single-phase or three-phase configuration to form a medium voltage AC interface, and each module comprises two quadrant switches with no active front end. The system includes a controller configured to generate voltage references for each module, the voltage references comprising a DC common-mode component and an AC differential-mode component, and optionally an AC common-mode component, wherein the DC common-mode component ensures unidirectional voltage operation across the medium voltage port of each module. The low voltage ports are interconnected to form a low voltage DC interface. The isolated DC-DC converter modules utilize conversion topologies including frequency modulated resonant converters, phase-shift modulated converters, and hybrid conversion topologies, operating at frequencies between 20 kHz and 100 kHz to achieve soft switching operation over wide operating ranges for improved efficiency and simplified manufacturability.

The application provides an alternating current charging and discharging system and an alternating current charging and discharging control method of a vehicle, which comprises a plurality of first windings of a first motor of an electric drive system, a plurality of first inverters of the electric drive system, a direct current bus, an active front-end rectifier and a controller; the first windings are respectively connected to the first inverters; the plurality of first inverters are connected in parallel to the direct current bus, and a first isolation switch is arranged on the direct current bus between two adjacent first inverters; one end of the direct current bus is connected to a battery of the vehicle, and the other end of the direct current bus is connected to the active front-end rectifier; the controller is configured to control the opening and closing of the first isolation switch; when the first isolation switch is closed, the first motor outputs a torque; when the first isolation switch is opened, the plurality of first windings and the plurality of first inverters realize DC / DC energy transmission and electrical insulation isolation of alternating current charging and discharging; and after the first isolation switch is opened, a high-frequency pulse voltage is generated at the bridge arm end of the first inverter.

The application discloses a kind of high-power IGBT rectifying system and method, it is related to the technical field of IGBT rectification, including active front-end rectification main circuit is constructed;Integrated dc side hybrid harmonic modulation auxiliary circuit;Multiple delay signal elimination operation is carried out to the signal obtained by sampling, filter harmonic interference signal, the frequency and phase of grid fundamental voltage are locked by phase-locked loop;Establish the control structure of voltage outer loop and current inner loop, generate the instruction amplitude of net side active current and ideal sine current reference waveform, and real-time control IGBT in active front-end rectification main circuit;Actual input current of net side is analyzed in real time by fast fourier transform, and residual harmonic component is identified;Realize the feedback management of regenerative energy.The application proposes a kind of active front-end IGBT rectification method and system with high adaptability of fusion type, which can operate stably under grid voltage distortion conditions, and realize deep harmonic suppression and high efficient energy bidirectional flow.

The present invention pertains to a power electronic converter, such as an inverter or converter, for an electric application such as a motor drive, electrolyzer or charger. The power electronic converter includes a DC link and an active front end (AFE) connected to grid via a filter and a grid board with a first inrush relay with a resistive device. The resistive device may be a resistor, more specifically an NTC resistor or a PTC thermistor. The grid board further includes a second inrush relay, wherein at least one of the inrush relays is controlled to engage or disengage during startup phase of the power electronic converter and during abnormal grid voltage conditions, such that the DC link is charged via the resistive device or by bypassing the resistive device, and such that the AFE is provided for boosting the DC link voltage to a save level and under controlled conditions. The invention also pertains to an electric motor drive according and a method for operating a power electronic converter.

A system for dissipating energy stored in a battery system includes a direct current (DC)-DC converter, an active front end (AFE), and a controller including one or more memories and one or more processors. The one or more processors are configured to determine a current state of charge (SOC) of the battery system; retrieve, from the one or more memories, the minimum energy value to be maintained in the battery system; compare the current SOC of the battery system with the minimum energy value; and dissipate the energy stored in the battery system if the current SOC is greater than the minimum energy value through the DC-DC converter, the AFE, both of the DC-DC converter and the AFE, and / or both of a first semiconductor device of the DC-DC converter and a second semiconductor device of the AFE.

Electronic devices and methods for controlling them. A method for controlling an electronic device comprising an AC input interface, an AC output interface, a DC bus, a battery interface, a bidirectional AC / DC active front-end (AFE) driver circuit, a bidirectional DC / DC converter, and an electronic processor, comprises determining a difference between a power level available from the AC input interface and a power demand at the AC output interface, and, if the power demand at the AC output interface is greater than or equal to the available power level, (i) controlling an output switch between the AFE driver circuit and the AC output interface to a closed state, and (ii) controlling the AFE driver circuit and the bidirectional DC / DC converter.to provide additional AC output power at the AC output interface using stored energy from a battery electrically connected to the battery interface.

The present invention provides a generator for a DC propulsion marine vessel based on DC power and a control method thereof. The generator for a DC propulsion marine vessel according to one embodiment of the present invention includes a synchronous generator that generates an AC voltage, an active front end (AFE) converter connected to an output terminal of the synchronous generator and converting the AC voltage into a DC voltage, and an automatic voltage regulator (AVR) that controls a field current so that a magnetic flux of a stator of the synchronous generator is maintained at a constant magnetic flux, and a sensor for measuring a rotational speed of the synchronous generator may be omitted.

The purpose of the present invention is to provide a power generation device for direct-current propulsion of a ship based on a direct-current power source and a control method therefor, the power generation device for direct-current propulsion of a ship according to one embodiment of the present invention comprising: a synchronous generator for generating an alternating-current voltage; the active front-end converter is connected to the output end of the synchronous generator and is used for converting the alternating-current voltage into direct-current voltage; and an automatic voltage regulator performing feedback control on an excitation current so that a magnetic flux of the synchronous generator or an output DC voltage of the active front-end converter is maintained constant, and a sensor for measuring a rotational speed of the synchronous generator may be omitted.

The utility model provides a power system based on variable frequency driving and a floating liquefied natural gas production, storage and unloading device, the power system comprises a power device and a variable frequency driver, the power device at least comprises a plurality of induction motors and power equipment, the induction motors are used for electrically driving the power equipment, and the variable frequency driver is used for electrically driving the power equipment. The power equipment comprises at least one of a water injection pump and gas compression equipment; the variable frequency driver is electrically connected with the input end of at least one induction motor, the variable frequency driver is used for driving the power device in a variable frequency mode, the variable frequency driver at least comprises a plurality of variable frequency units, and one variable frequency unit comprises an active front-end rectifier and a passive front-end rectifier. The performance of the power system can be improved.

The application provides a single-phase power electronic transformer and a control method, and belongs to the technical field of power electronic transformers.The single-phase power electronic transformer comprises a plurality of power modules, which are cascaded at a high-voltage alternating-current port and are connected in parallel at a low-voltage direct-current port; each power module comprises two solid-state switches, a high-voltage positive H-bridge unit, a high-voltage negative H-bridge unit, two high-frequency transformers and a low-voltage H-bridge unit; the two solid-state switches are connected in parallel with the high-voltage positive H-bridge unit and the high-voltage negative H-bridge unit, respectively; the alternating-current sides of the high-voltage positive H-bridge unit and the high-voltage negative H-bridge unit are connected to the high-voltage side windings of the two high-frequency transformers, respectively; the low-voltage side windings of the two high-frequency transformers are connected at different names; and the same name ends of the two high-frequency transformers are connected to the low-voltage H-bridge unit.The single-phase power electronic transformer provided by the application does not need an active front-end H-bridge unit, reduces the number of power conversion stages and has high operation efficiency.

A power module includes a power substrate, a number of power semiconductor die, and a number of connector pins. The power substrate includes a number of conductive traces. The power semiconductor die are mounted on the power substrate and electrically coupled to the conductive traces. The connector pins are each electrically coupled to a different one of the conductive traces and configured to be interconnected such that the power semiconductor die provide an active front-end and a switching power converter. By providing the power semiconductor die such that they can be interconnected to form an active front-end and a switching power converter in the same power module, the power module may provide a significantly more compact power converter system using both an active front-end and switching power converter.

The invention discloses a gas turbine control system, method and device and electronic equipment, and belongs to the technical field of gas turbine control, the system comprises a first circuit breaker, a second circuit breaker, a third circuit breaker, an active front end (AFE), a frequency converter (VFD), an uninterruptible power supply (UPS), a gas turbine and a controller, the first circuit breaker is connected between the UPS and a pre-charging circuit of the AFE, and the second circuit breaker is connected between the UPS and a pre-charging circuit of the AFE. The second circuit breaker is connected between the UPS and the alternating-current end of the AFE, the third circuit breaker is connected between a power grid or a load and the alternating-current end of the AFE, the direct-current end of the AFE is electrically connected with the direct-current end of the VFD, the alternating-current end of the VFD is electrically connected with the gas turbine, and the gas turbine can stably operate in an island mode through the system.

The invention relates to a power electronic converter, such as an inverter or converter, for electrical applications, such as motor drives, electrolyzers or chargers. The power electronic converter includes a DC link and an active front end (AFE) connected to a grid via a filter and a grid plate. The grid plate has a first surge relay. The first surge relay has a resistive device. The resistive device may be a resistor, more specifically an NTC resistor or a PTC thermistor. The power grid plate further comprises a second surge relay. During a start-up phase of the power electronic converter and during abnormal grid voltage conditions, the at least one surge relay is controlled to turn on or off such that the DC link is charged via or bypassing the resistive device, and the AFE is used to boost the voltage of the DC link to a safety level and in a controlled condition. The invention also relates to an electric motor drive and to a method for operating a power electronic converter.

Techniques to reduce discontinuities in power, for example, by controlling an electrical power output of an active front end unit during a transition between a first operating mode and a second operating mode. In some examples, to reduce discontinuities, a control unit of the active front end unit can seed the integrator of proportional-integral (PI) controllers that are brought online during the operating mode change with a value that represents the proper state of the current system, such as the measured or calculated value of the component the PI controller is controlling). In other examples, to reduce discontinuities, a control unit of the active front end unit can control reference frame alignment during a transition between a first operating mode and a second operating mode.

A system (104) for dissipating energy stored in a battery system (102) includes a direct current (DC)-DC converter (104), an active front end (AFE) (108), and a controller (112) including one or more memories (114) and one or more processors (116). The one or more processors (116) are configured to determine a current state of charge (SOC) of the battery system (102); retrieve, from the one or more memories (114), the minimum energy value to be maintained in the battery system (102); compare the current SOC of the battery system (102) with the minimum energy value; and dissipate the energy stored in the battery system (102) if the current SOC is greater than the minimum energy value through the DC-DC converter (104), the AFE (108), both of the DC-DC converter (104) and the AFE (108), and / or both of a first semiconductor device (106) of the DC-DC converter (104) and a second semiconductor device (110) of the AFE (108).

The disclosure relates to a rectifier (1) for rectifying alternating current from a power source (80) with N phases (PA, PB, PC), wherein N is at least two. It includes a power input (2) for connection with the power source (80), an LCL filter (30) connected to the power input (2) via an interruption unit (40), an active front end (10) with at least two levels that includes a direct current bus (11) and is connected to the power input (2) via the LCL filter (30) and the interruption unit (40). The interruption unit (40) is switchable to an interrupting state in which it disconnects the LCL filter (30) and hence the active front end (10) from the power input (2) for N-1 phases (PA, PB), said N-1 phases (PA, PB) including a first phase (PA). The rectifier (1) has an inrush protection bypass (50) for bypassing the interruption unit (40) for the first phase (PA). In order to provide reliable and cheap protection from excessive inrush currents for the rectifier (1) while allowing for particularly high efficiency of the rectifier (1) in normal operation, the inrush protection bypass (50) is conductive only for current flow in one specific direction.

SOLUTION: A signal collection unit and a battery module are disclosed, in which the signal collection unit contains: a plastic support 1; a bus bar 2; a first printed circuit board (PCB) substrate 3; and a flexible flat cable (FFC) connection wire 4, the bus bar is distributed to one side surface that is separated from a cell of the plastic support, the first PCB substrate is arranged to the plastic support, an active front end (AFE) is collected to the first PCB substrate, and the FFC connection wire includes an input end connected to the bus bar, and an output end electrically connected to the AFE.EFFECT: A connection distance between a signal collection unit and an active front end (AFE) can be effectively reduced. In a signal transmission step to the AFE, an interference received by a flexible flat cable (FFC) connection wire can be effectively reduced, and a transmission accuracy of a signal can be secured. Also, in a step of transmitting the signal to a battery management system (BMS), the number of relay cables is small, a cost is low, and two cables is hardly dislocated, and thus a failure rate at their place can be largely reduced.SELECTED DRAWING: Figure 1

The invention relates to an electrical power converter, in particular for an MVAC / LVAC to LVDC electrical power conversion drive, comprising an active front end (AFE), a transformer and an LCL filter having a grid-side choke and a drive-side choke. According to the invention, the transformer and the LCL filter are at least partially magnetically bonded to each other.

The application discloses an active front-end rectifier and a prediction control method thereof, and the method comprises the following steps: according to a voltage model of a three-level active front-end rectifier, calculating active power and reactive power of a power grid according to instantaneous power theory; according to the voltage model, combining the active power and the reactive power, calculating a power gradient; converting the power gradient into a second-order state space equation, predicting the control input of the active front-end rectifier by using a super-helix observer, and obtaining the input voltage of the active front-end rectifier according to the predicted control input and the grid-side voltage; based on the input voltage, obtaining an optimal voltage vector by using a limited set model prediction control framework, and controlling the active front-end rectifier based on the switching state corresponding to the optimal voltage vector. The method combines power gradient modeling, super-helix observer disturbance compensation and limited set prediction control, so that the rectifier overcomes the influence of parameter mismatch, and realizes high-sinusoidal current, stable DC voltage and power tracking control.

This invention discloses a method for transient control of module voltage in a wideband and wide-voltage device. The wideband and wide-voltage device of this invention includes an input transformer, a converter valve, and an output transformer. The converter valve adopts a three-phase independent configuration, with each phase consisting of multiple cascaded dual H-bridge modules. Each dual H-bridge module includes an active front-end H-bridge and an inverter H-bridge. The control methods for the active front-end H-bridge and the inverter H-bridge are improved and optimized: the active front-end H-bridge employs a constant DC voltage control strategy to achieve real-time balance of the module's DC side voltage; the inverter H-bridge employs a carrier phase-shift modulation strategy. By simultaneously controlling the active front-end H-bridge and the inverter H-bridge, this invention promotes the rapid dissipation of voltage accumulation within the module, effectively suppresses voltage rise, and rapidly suppresses voltage fluctuations under transient conditions, preventing overvoltage damage and ensuring the safe and stable operation of the module under transient conditions.

Electronic devices and methods of controlling the same. One method of controlling an electronic device including an AC input interface, an AC output interface, a DC bus, a battery interface, a bidirectional AC / DC active front end (AFE) drive circuit, a bidirectional DC / DC converter, and an electronic processor includes determining a difference between a power level available from the AC input interface and a power demand at the AC output interface, and, in response to the power demand at the AC output interface being greater than or equal to the available power level, (i) controlling an output switch between the AFE drive circuit and the AC output interface to a closed state and (ii) controlling the AFE drive circuit and the bidirectional DC / DC converter to provide supplemental AC output power at the AC output interface using stored energy from a battery electrically connected to the battery interface.

A regenerative drive system includes a plurality of power cells receiving power from a source and supplying power to one or more output phases, wherein each power cell is operable in multiple operation modes, each power cell including multiple switching devices including active front-end switching devices, and a central control system controlling operation of the plurality of power cells, wherein the central control system is configured to control the active front-end switching devices of each power cell with variable conduction angles in the multiple operation modes.