224results about "Conversion with reversal" patented technology

Disclosed is a multi-port charger capable of charging a higher-voltage battery by boosting low DC charging voltage using an on-board charger (OBC) installed in a vehicle without adding a separate part or device and capable of being used for various applications, such as V2G and V2L, in addition to charging.

The invention relates to the technical field of power electronics, and particularly provides a double-rectification single-inversion redundant uninterruptible power supply system and a control protection method thereof, and the system comprises a power distribution system, a variable current power module and a control protection system. The power distribution system has double AC inputs, a common DC bus and AC outputs. The converter module comprises three converters, two of which serve as rectifiers and are connected in parallel with the direct current bus, and the other one serves as inverter output. The control method comprises the following steps: in a double-path load balancing mode, realizing power equalization through composite voltage control; in a single-path operation mode, fault seamless switching is realized based on load feedforward and adaptive slope control; in a power distribution mode, triggering according to capacity margin and cooperatively adjusting a droop coefficient based on an optimization target to realize power redistribution; and complete real-time fault protection logic is realized. According to the invention, uninterruptible power supply with high reliability and high electric energy quality is realized, and active regulation and control of power are realized.

The invention discloses an energy storage converter cabinet with double DC / DC converters. The energy storage converter cabinet comprises a cabinet body, a bidirectional DC / AC converter, a first DC / DC converter, a second DC / DC converter, a common DC bus and a central controller, the AC side of the bidirectional DC / AC converter is connected with a local AC load and / or a power grid, and the DC side is connected with a common DC bus; the low-voltage end of the first DC / DC converter is connected with the battery pack, and the high-voltage end is connected with the common DC The first end of the second DC / DC converter is connected with the photovoltaic array, and the second end is connected with the common DC bus; the central controller is connected with the bidirectional DC / AC converter, the first DC / DC converter and the second DC / DC converter; according to the power grid instruction, the battery state and the photovoltaic power generation condition, the bidirectional DC / AC converter, the first DC / DC converter and the second DC / DC converter are controlled, and photovoltaic power, battery power and power grid power are dispatched in real time.

An electrical converter may include AC terminals, a first and second DC terminal, and converter modules. Each of the converter modules has an AC node. The second DC terminal forms a common node of the converter modules. A connection between the AC nodes of the converter modules and the AC terminals is reconfigurable allowing the electrical converter to operate according to a first mode of operation converting between a first AC signal having a first plurality of phase voltages and the DC signal, in which the converter modules are grouped in first groups, and according to a second mode of operation converting between a second AC signal having a single-phase voltage and the DC signal, in which the converter modules are rearranged in second groups. The electrical converter is configured to operate multiple converter modules assigned to a same group of the first groups and the second groups in parallel.

The invention discloses a bidirectional DC-AC converter control method considering a soft switching condition and current optimization. According to the invention, the switching loss of the converter is reduced by optimizing the phase shift angle and the switching condition of the converter, and the energy transmission efficiency is optimized by minimizing the effective value of the current, so that the performance of the whole sodium battery energy storage system is improved. Specifically, based on the relation between the excitation inductance Lm and the current effective value Iprms, the phase shift angle of the converter is accurately controlled, the current transmission efficiency is optimized, and it is ensured that the zero-voltage switching condition of a primary side bridge arm and a secondary side bridge arm can be achieved in the working process, so that the loss of the converter is remarkably reduced, and the energy conversion efficiency is improved.

A power supply circuit and an energy storage device are provided. The power supply circuit includes a DC / DC conversion module, a first AC / DC conversion module, a second AC / DC conversion module, an alternating current input interface, a first alternating current output interface, and a second alternating current output interface. A first end of the first AC / DC conversion module is connected to a battery module through the DC / DC conversion module, a first end of the second AC / DC conversion module is connected to the first end of the first AC / DC conversion module through a direct current bus, the first alternating current output interface is connected to a second end of the first AC / DC conversion module and a first terminal of the alternating current input interface, the second alternating current output interface is connected to a second end of the second AC / DC conversion module, both the first AC / DC conversion module and the second AC / DC conversion module may operate in a rectification mode or an inversion mode, and the DC / DC conversion module operates in a discharging mode or a charging mode.

Charging device comprising: a battery (106) suitable and configured to store DC voltage; first and second motors (101, 102) suitable and configured to operate as a motor or a generator; first and second inverters (103, 104) suitable and configured to operate the first and second motors (101, 102); a voltage transformer (105) suitable and configured to increase the DC voltage of the battery (106) to supply it to the first and second inverters (103, 104) and to increase the DC voltage of the inverter to supply it to the battery (106); and a charging controller (200) suitable and configured to operate the first and second inverters (103, 104) as a booster or generator.to operate voltage amplifiers or to operate the voltage transformer (105) as a step-down converter, according to a voltage which is input via a neutral point of the first and second motors (101, 102) and the voltage of the battery (106), wherein the charging control element (200) is configured to switch off the voltage transformer (105) so that the voltage which is increased by the first inverter (103) or the second inverter (104) charges the battery (106) when the voltage which is input via the neutral point of the first and second motors (101, 102) is less than the battery voltage.

The invention discloses a self-adaptive control method and system for an outdoor energy storage converter, and the method comprises the steps: a current inner loop control process: carrying out the decoupling control of a current inner loop of the outdoor energy storage converter through a feedforward decoupling control strategy based on a dq model of the outdoor energy storage converter; in the voltage outer loop control process, adjustable parameters of the outdoor energy storage converter are obtained, the adaptive law of the outdoor energy storage converter is obtained through a Narendra stable adaptive control algorithm, and the influence of parameter changes of a controlled object on a control result is counteracted by continuously changing the adjustable parameters; in the smooth switching control process, the output voltage of the outdoor energy storage converter is adjusted by obtaining the voltage frequency, amplitude and phase information of the power grid side and / or the load side according to the current inner loop control process and the voltage outer loop control process, and grid-connected and off-grid switching is conducted on the outdoor energy storage converter; according to the invention, the stable operation of the outdoor energy storage converter is ensured, and the system robustness is enhanced.

This invention proposes a method and system for coordinated charging and discharging of electric vehicles based on energy storage substations. This method is used to solve the problems of transformer overload and three-phase load imbalance during charging and discharging. The core steps include: Step 1: The centralized controller acquires real-time substation operation data and uploads it to the cloud service controller for analysis; Step 2: Determines whether load imbalance and transformer overload exist; Step 3: When load imbalance and substation transformer overload are detected, a substation scheduling and control model is established to optimize the charging and discharging loads of energy storage batteries, AC charging piles, and DC charging piles; Step 4: Finds the optimal load switching scheme based on the model; Step 5: Evaluates the load balance improvement effect; If the load imbalance exceeds the adjustment range or exceeds the transformer load rate threshold, the DC charging pile can be connected to the 10kV incoming line via the second branch boost inverter where the inverter is located.

The application discloses a power assembly and a liquid-cooled converter, the power assembly comprising a capacitor module, a power module and a radiator; the capacitor module comprises DC capacitor banks and a capacitor busbar connected with each other; the power module comprises an input busbar, an output busbar and three single-phase switch tube groups, each single-phase switch tube group comprising a plurality of switch modules and being connected to the input busbar and the output busbar; the input busbar is connected to the connecting part; the output busbar is used for outputting electric energy; and all single-phase switch tube groups in the power module are mounted on the radiator, and the arrangement direction of each switch module in each single-phase switch tube group is parallel to the connecting part. The power assembly can solve the problem of large volume of the existing power assembly.

The application provides a control method of a converter and an energy storage system. The method is applied to a bidirectional converter; a first port of the bidirectional converter is provided with a first capacitor, and a second port of the bidirectional converter is provided with a second capacitor; the control method comprises the following steps: obtaining a voltage effective value of the first port and a voltage effective value of the second port; if the voltage effective value of the first port is greater than a first preset voltage or the voltage effective value of the second port is greater than a second preset voltage, the bidirectional converter is controlled to alternately work in a first conversion state and a second conversion state until the voltage effective value of the first port is not greater than the first preset voltage and the voltage effective value of the second port is not greater than the second preset voltage. The application only controls the switching tube of the bidirectional converter to work alternately, continuously consumes the stored energy until the port voltage meets the requirement, and the control method is simple, and a separate discharge circuit is not needed, so that the circuit complexity is reduced.

This utility model discloses a water-cooled energy storage converter, including a cabinet. The cabinet is divided into an independent electrical cavity, a reactor cavity, and a water-cooling cavity, with the water-cooling cavity positioned at the top. The water-cooling cavity and the electrical cavity are interconnected for water circulation heat exchange. The reactor cavity is independently cooled by forced air cooling or water cooling. This utility model features a compact structure, high space utilization, high stability, and good heat dissipation. The water-cooling system is integrated inside the converter, minimizing the cabinet size and significantly reducing transportation and land costs. It overcomes the shortcomings of existing water-cooled converters, such as low integration and large footprint.

A control method for an alternating current (AC) / direct current (DC) conversion circuit includes: controlling the AC / DC conversion circuit to operate in a first drive mode, where in the first drive mode, a switching frequency of a switching transistor of a first bridge arm is a first frequency, and a switching frequency of a switching transistor of a second bridge arm is a second frequency; determining a switching moment based on an alternating current side voltage of the AC / DC conversion circuit when an operating status of the AC / DC conversion circuit satisfies a preset condition; and controlling the inverter circuit to operate in a second drive mode from the switching moment, where in the second drive mode, the switching frequency of the switching transistor of the first bridge arm is the second frequency, and the switching frequency of the switching transistor of the second bridge arm is the first frequency.

A gravity energy storage system suitable for a meteorite crater environment comprises a gravity energy storage device, a motor drive / power generation device and an energy conversion and power supply device. The motor driving / generating device comprises a permanent magnet synchronous motor and a direct current motor; the energy conversion and power supply device comprises a first bidirectional power converter, a second bidirectional power converter and a boost converter, the second bidirectional power converter is electrically connected with the photovoltaic array through the boost converter and electrically connected with a power grid through the first bidirectional power converter, and the direct current motor is electrically connected with the photovoltaic array through the boost converter. And the first bidirectional power converter is electrically connected with a power grid. The natural elevation difference of the meteorite crater is utilized, rocks around and inside the meteorite crater serve as gravity energy storage loads, and storage and release of gravitational potential energy are achieved through lifting and lowering of a mine car or a cable car along a transportation channel. According to the system, a photovoltaic array and a power grid are used as dual-power input, and bidirectional conversion and grid-connected output of energy are realized through switching between a driving mode and a power generation mode by a bidirectional power converter and a motor, so that the dependence of a gravity energy storage system on an artificial structure and an external weight is reduced, and the adaptability of the system to a complex terrain environment is improved.

The invention relates to the technical field of power electronic control, and discloses an ACDC bidirectional single-stage energy storage converter and a modulation method thereof, and a storage medium, through configuring a power control unit, an energy conversion unit, a filtering unit and a bus capacitor into a whole, dual functions of boost inversion and rectification voltage reduction are realized, the integration level of a system is significantly improved, and the system reliability is improved. Particularly, bidirectional unobstructed flow of power is realized based on the energy conversion unit, the energy storage converter can be ensured to stably work in a bidirectional mode of discharging and charging, and a first SPWM modulation signal and a second SPWM modulation signal are generated through a plurality of pre-configured signals. Therefore, the turn-off states of the third switch tube and the fourth switch tube are controlled based on the first SPWM modulation signal, and the turn-off states of the first switch tube and the second switch tube are controlled based on the second SPWM modulation signal, so that the complementary turn-off control of the switch tubes is realized, and the high efficiency of the energy storage converter in different application occasions is maintained. The device is especially suitable for application occasions with low power and high portability requirements.

The invention discloses a power control method and device for a self-adaptive virtual impedance network-building type energy storage converter, and belongs to the technical field of generator control, and the method comprises the steps: analyzing the parallel operation circuit topology of the network-building type energy storage converter, building a mathematical model, and building a VSG control model containing a virtual impedance unit; based on a model reference adaptive control principle, taking a power distribution error as input, deducing an adaptive updating law of a virtual impedance parameter by utilizing a Lyapunov stability theory, and designing a model reference adaptive controller; and applying the model reference adaptive controller to the VSG control model, dynamically adjusting the virtual impedance, and performing distribution control on the power of the converter. According to the method, the power distribution precision can be improved by adaptively adjusting the virtual impedance and compensating the line impedance difference and the parameter change.

The invention discloses a control method of an electric energy conversion circuit, the electric energy conversion circuit and an energy storage system, the electric energy conversion circuit is connected between an input port and a battery port, the electric energy conversion circuit comprises a driving module and a plurality of switch tubes, at least one switch tube is a discharge switch tube, the driving module comprises a grounding end and a working voltage end for supplying power to the driving module, the leakage switch tube is connected to the grounding end and a reference ground, and the control method comprises the following steps: detecting the working state of the electric energy conversion circuit; and when it is detected that the electric energy conversion circuit is in a non-working state, the discharge switch tube is controlled to be switched on, and the working voltage end and the reference ground form a discharge loop through the grounding end, so that the quiescent current of the driving module is discharged through the discharge loop. According to the control method, when the electric energy conversion circuit does not work, the leakage switch tube is actively controlled to be transiently conducted, a to-ground leakage path is provided for the quiescent current of the working voltage end, therefore, false voltage is prevented from being generated at the input port, and the misjudgment phenomenon of the system is avoided.

The embodiment of the application discloses a modular bidirectional converter and a phase locking method thereof. The bidirectional converter comprises a conversion circuit composed of multiple modules; each module corresponds to a module control card; a first end of the conversion circuit is connected with a direct-current traction network, and a second end of the conversion circuit is connected with an alternating-current power grid; a system control card is configured to, in a post-buffer starting stage, perform phase locking on the alternating-current power grid to obtain a first phase, and synchronize the first phase to the module control card, so that the module control card controls the output voltage of the module based on the first phase; the post-buffer starting stage represents that the voltage of a direct-current side bus of the conversion circuit has been buffered to a first threshold value, and the buffer starting stage comprises the post-buffer starting stage; the module control card is configured to, in a non-buffer starting stage, perform phase locking on the alternating-current power grid to obtain a second phase, and control the output voltage of the module based on the second phase; and the non-buffer starting stage represents a state in which the alternating-current side of the bidirectional converter is completed and the module control card can sample the alternating current.

The charging / discharging device is connected to a power grid through a first cable and a plug, and to an electric vehicle through a second cable and a connector. The charging / discharging device includes a charging circuit, a reverse flow circuit, and a controller, where the charging circuit provides a charging path that supplies power from the power grid from the plug to the connector, and the reverse flow circuit provides a reverse flow path that supplies power from the connector to the plug. In a charging mode, the controller sets a first current through the charging path, and in a reverse flow mode, the controller sets a second current through the reverse flow path. The present disclosure also relates to a charger for an electric vehicle.

The present disclosure relates to a direct-current / alternating-current conversion circuit and an energy storage and conversion apparatus. The direct-current / alternating-current conversion circuit comprises: three single-phase conversion circuits, a first end of each single-phase conversion circuit being a direct-current end, a second end of the single-phase conversion circuit being an alternating-current end, and the single-phase conversion circuit being used for mutual conversion between a direct-current current and a single-phase alternating-current current. When the second ends of the three single-phase conversion circuits are shorted, the alternating-current phases of the three single-phase conversion circuits are the same, and when the second ends of the three single-phase conversion circuits are not shorted, phase differences exist among the alternating-current phases of the three single-phase conversion circuits. The direct-current / alternating-current conversion circuit can be compatible with a three-phase power grid and a single-phase power grid, so that an energy storage device using the direct-current / alternating-current conversion circuit has good flexibility during grid connection.

Even in the event of a malfunction in the vehicle's control system, this prevents the unintended application of external power voltage to electrical equipment connected to the vehicle's power supply port. [Solution] The power conversion system 110 comprises an inlet 107, an outlet 108, a power conversion device 120, electrical contacts 142 and 162, and a control device 170. The power conversion device 120 converts the power received by the inlet 107 to charge the battery 105, or converts the power from the battery 105 to supply to the outlet 108. Electrical contact 142 is provided on a first power line extending from the inlet 107 to the power conversion device 120. Electrical contact 162 is provided on a second power line extending from power lines PL1b and PL2b to the outlet 108 and is opened and closed complementaryly with electrical contact 132. The control device 170 generates a control signal CS1 to control the operating state of both electrical contacts 132 and 152.

The invention provides a cascade system control method and a cascade system, the cascade system comprises a first inductor and N power modules (N is an integer greater than or equal to 2), each power module is provided with a first side and a second side, a branch formed by connecting the first sides of the N power modules in series bears a first voltage, and the second side of the N power modules bears a second voltage. The second side of each power module is subjected to a second voltage. Each power module includes a switch operating with a switching cycle. And determining the number of the power modules working in the high-frequency modulation mode according to the ratio of the first voltage to the second voltage, so that the moment when the current flowing through the switch is 0 exists in one switching period. The invention provides a soft switching solution, which can reduce the turn-on loss and is favorable for improving the power density of the cascade system. The condition that ZVS cannot be realized when the duty ratio is about 0 or 1 in a carrier cascading modulation means and the condition that ZVS cannot be realized due to ripple cancellation in a carrier phase-shifting modulation means can be avoided.

The application provides an inverter circuit control method and device and an inverter module, and relates to the technical field of power electronics. The inverter circuit control method comprises the following steps: acquiring a detected AC parameter of an inverter circuit and a detected DC parameter of the inverter circuit; determining a switching control parameter of the inverter circuit according to the detected AC parameter, a corresponding given AC parameter, the detected DC parameter and a corresponding given DC parameter; and determining a switching control signal according to the switching control parameter, the switching control signal being used for controlling a switching unit of the inverter circuit. According to the given DC parameter of the DC side, the given AC parameter of the AC side and the detected AC parameter and the detected DC parameter, the switching control parameter of the inverter circuit is determined, then the switching control signal is determined according to the switching control parameter, the control of the inverter circuit is realized, the mutual constraint between the DC side and the AC side is realized, and the comprehensive optimization control is more favorable.

The invention belongs to the field of energy storage converters, and discloses an energy storage converter suitable for being compactly placed in a station, which comprises a converter shell, a first protective electrical assembly, a hollow radiator, a protective cover shell and a heat exchange core body, and is characterized in that the converter shell is provided with an air inlet space, a component space and an air outlet space; the hollow radiator and the protective cover form an air-passing heat dissipation channel which is closed in the circumferential direction, other part spaces except the air-passing heat dissipation channel serve as sub-spaces outside the channel, the first protective electrical assembly is located in the sub-spaces outside the channel, and the converter shell is provided with a first air inlet, a second air inlet and an air outlet. The second air inlet communicates with the air inlet space through a cold side channel of the heat exchange core body, the first air inlet communicates with the air inlet space, the air outlet selectively faces the same direction as the first air inlet and the second air inlet, and the air outlet correspondingly communicates with the air outlet space. The invention further discloses a heat dissipation method of the energy storage converter.

The application provides a kind of hybrid vector variable frequency control method based on three-phase rectifier, it is related to power electronic electric energy conversion technical field;Current three-phase PWM rectification technology is important front-stage equipment, and the current of switch tube is large, and the loss of switch tube is composed of turn-on loss and conduction loss, and conduction loss cannot be avoided in high-power state, and switch loss is related to frequency, if switch tube loss is not controlled, switch tube loss will accumulate in the form of heat, when temperature exceeds the limit of switch tube, it often causes irreversible damage to switch tube, therefore, on the basis of considering the power quality of DC side, the action frequency of switch tube of three-phase PWM rectifier is dynamically controlled to realize the continuous operation of three-phase PWM system under high power, and the method considers the stability of DC side voltage and the temperature characteristics of IGBT to carry out frequency modulation.

A converter (100), comprising: a bidirectional conversion circuit (12), a detection circuit (11), and a voltage detection module (13). The detection circuit (11) comprises a first resistor (111), a second resistor (112), a third resistor (113), a first switch (114), and a second switch (115). A first terminal of the first resistor (111) is electrically connected to a direct current positive terminal of the bidirectional conversion circuit (12). A second terminal of the first resistor (111) is connected to a first terminal of the second resistor (112). A second terminal of the second resistor (112) is connected to a first terminal of the third resistor (113). A second terminal of the third resistor (113) is electrically connected to a direct current negative terminal of the bidirectional conversion circuit (12). A connection point between the first resistor (111) and the second resistor (112) is electrically connected to the direct current negative terminal of the bidirectional conversion circuit (12) via the second switch (115), and a connection point between the second resistor (112) and the third resistor (113) is grounded via the first switch (114). The voltage detection module (13) is configured to acquire a voltage between the direct current negative terminal of the bidirectional conversion circuit (12) and ground. The converter (100) enables detection of insulation impedance to ground, and the sensitivity, accuracy, and response speed of the converter (100) in detecting ground short circuits can also be improved.

The application discloses a control method of a current source type converter based on a bidirectional switch, which comprises the following steps: firstly, obtaining a current sector where a three-phase current space vector is located; secondly, sampling three-phase voltages of the current source type converter by using a voltage detection circuit; thirdly, dividing the whole working interval into a main interval and a transition interval according to the three-phase voltage values; fourthly, using the same vector distribution table in the main interval and the transition interval; fifthly, not limiting the type of zero vector in each current sector; sixthly, adopting a two-step commutation mode in the main interval; seventhly, adopting a four-step commutation mode when commutation is performed between two phases with relatively close voltage values in the transition interval; and eighthly, adopting the two-step commutation mode in other cases. The control method can reduce the commutation time of the current source type converter, reduce the common-mode voltage in the transition interval of the converter, and reduce harmonic distortion, so as to guarantee the efficient and reliable operation of the current source type converter system.

This utility model provides a bidirectional charging and discharging system for ship-shore use, relating to the field of ship energy supply technology. It includes a high-voltage input module, an AC power distribution module, a low-voltage power distribution module, an AC / DC conversion module, and cable equipment. The high-voltage input module connects to a shore-based AC power source, which is stepped down by a first transformer to supply power to the low-voltage power distribution module. The voltage is then stepped down by a second transformer and output as DC power via the AC / DC conversion module to charge the ship's energy storage unit. The AC / DC conversion module employs a bidirectional AC / DC conversion structure, enabling bidirectional power transmission between the ship and the shore-based power grid. The system uses a modular prefabricated structure, isolating the AC and DC side functional units to improve system integration and operational efficiency. It also ensures flexible switching between shore power supply and ship energy storage discharge during ship berthing, possessing excellent energy regulation capabilities and grid adaptability.

The application discloses a control method and device of a balanced bridge circuit, electronic equipment and a storage medium, relates to the technical field of balanced bridges, and obtains a neutral line voltage deviation value signal; controls the direct current and the alternating current of the neutral line voltage deviation value signal based on at least two control loops, obtains a direct current control signal and an alternating current control signal; adjusts an adjustment coefficient based on the neutral line voltage deviation value signal, and obtains a target adjustment coefficient; fuses the direct current control signal and the alternating current control signal based on the target adjustment coefficient, obtains a target control signal, and controls the balanced bridge based on the target control signal. The control method of the balanced bridge circuit controls the direct current and the alternating current of the neutral line voltage deviation value signal respectively, adjusts the adjustment coefficients of different control signals adaptively, and solves the problem of heating of the neutral line capacitor without affecting the control effect of the original positive bus voltage and the negative bus voltage.

The invention relates to a direct current exchange conversion circuit, which comprises three single-phase conversion circuits, the first ends of the single-phase conversion circuits are direct current ends, the second ends of the single-phase conversion circuits are alternating current ends, and the single-phase conversion circuits are used for mutual conversion between direct current and single-phase alternating current; under the condition that the second ends of the three single-phase conversion circuits are short-circuited, the alternating current phases of the three single-phase conversion circuits are consistent, and under the condition that the second ends of the three single-phase conversion circuits are not short-circuited, the alternating current phases of the three single-phase conversion circuits have phase differences. The DC-AC conversion circuit can be compatible with a three-phase power grid and a single-phase power grid, so that the energy storage equipment applying the DC-AC conversion circuit has better flexibility during grid connection.