Abstract: An energy storage module includes a bus connection part, a battery pack, a capacitor and a series compensation DC conversion device. A first conduction terminal of the series compensation DC conversion device is electrically connected with a positive bus connection terminal and a negative bus connection terminal of the bus connection part, or the first conduction terminal is connected with a battery positive terminal and a battery negative terminal of the battery pack. A second conduction terminal of the series compensation DC conversion device is electrically connected with two terminals of the capacitor. A four-quadrant DC/DC converter of the series compensation DC conversion device controls the capacitor to generate a compensation voltage to compensate a voltage between the two terminals of the battery pack, or the four-quadrant DC/DC converter adjusts a current flowing through the battery pack to a set value.

Abstract: The present disclosure provides a three-phase AC system and a control method thereof. The method includes: receiving an output signal of the three-phase AC system and obtaining a characteristic value of the output signal according to the output signal; performing virtual synchronous generator control on the inverter to obtain a fundamental electric potential; extracting a harmonic component from the output signal and obtaining an error signal according to the harmonic component and a reference value of the harmonic component; controlling the error signal to obtain a harmonic compensation electric potential; obtaining a control electric potential by superimposing the harmonic compensation electric potential with the fundamental electric potential; obtaining a pulse signal by modulating the control electric potential, and obtaining a switching signal of the inverter according to the pulse signal.

Abstract: A lipid delivery system, a virus-like structure (VLS) vaccine constructed therefrom, and a lipid particle capable of encapsulating an mRNA molecule encoding a SARS-CoV-2-specific antigen are provided. After the lipid particle encapsulates an mRNA molecule encoding a SARS-CoV-2 antigen, a SARS-CoV-2 S1 antigen protein can be embedded on a surface of an envelope structure of the lipid under specific buffer conditions to produce a VLS vaccine with an antigen-encoding mRNA molecule encapsulated inside and an outer membrane presenting a required viral antigen protein. The vaccine has a superior specific antibody-inducing ability to a SARS-CoV-2 mRNA vaccine and a polypeptide vaccine, can maintain a long-lasting high antibody level, and can also exhibit excellent immune binding abilities for the emerging different variants.

Abstract: The application relates to battery internal resistance detection device and method for power conversion device. The detection device includes a data acquisition module for acquiring a battery voltage and a battery current to obtain a DC voltage, an AC voltage, a DC current and an AC current, a first calculation module for receiving the AC current and the AC voltage at a certain instant to output a first internal resistance value and a battery capacitance, a second calculation module for receiving a plurality of DC currents and a plurality of DC voltages at multiple instants and the battery capacitance to output a second internal resistance value, and a selection module for receiving the first and second internal resistance value and selecting one of the first and second internal resistance value as battery internal resistance value. The application improves detection accuracy of battery internal resistance by combining DC and AC algorithms.

Abstract: A high-voltage DC transformation apparatus, a power system and a control method of the power system. The high-voltage DC transformation apparatus is electrically connected to at least one high-voltage DC power generator. The high-voltage DC transformation apparatus includes at least one bidirectional AC/DC conversion module, at least one first transformer and at least one unidirectional rectifier module. A DC terminal of the bidirectional AC/DC conversion module is electrically connected to the corresponding high-voltage DC power generator. The first transformer includes a first transmission terminal and a second transmission terminal. The first transmission terminal is electrically connected to an AC terminal of the corresponding bidirectional AC/DC conversion module. The unidirectional rectifier module includes an input terminal and an output terminal.

Abstract: The present disclosure provides an islanding detection method for an inverter and a corresponding apparatus. The islanding detection method includes: step A1: obtaining a parameter of an output voltage of a three-phase AC system and a steady-state value corresponding to the parameter within a period of time; step A2: obtaining a disturbance signal based on the parameter and the steady-state value; step A3: superimposing the disturbance signal on at least one reference value of a droop control; and step A4: detecting the parameter added with the disturbance signal, and determining that island occurs in response to the parameter greater than an upper limit or less than a lower limit.

Abstract: An energy storage system is provided. The energy storage system includes a plurality of battery clusters, a plurality of power regulators, a transformer, and a central controller. The plurality of power regulators is configured to control charging and discharging of the plurality of battery clusters. Each power regulator is electrically coupled to corresponding two, at most, of the plurality of battery clusters. A first terminal of the transformer is electrically coupled to the plurality of power regulators, and a second terminal of the transformer is electrically coupled to the power grid. The central controller is coupled to the plurality of power regulators and the plurality of battery clusters for controlling the plurality of power regulators and the plurality of battery clusters. The central controller is in communication with the plurality of power regulators through optical fibers, and a data transmission rate of the optical fibers is greater than 1 Mbit/s.

Abstract: A power conversion system is coupled between a power grid and a load. The power conversion system includes a battery, a first converter, a second converter and a DC/DC converter. The first converter is configured to selectively convert an input power from the power grid into a first charging power when the power grid is operated normally. The second converter is configured to convert the input power from the power grid into an output power when the power grid is operated normally. The DC/DC converter is electrically connected between the battery and the second converter. The DC/DC converter is configured to convert a storage power in the battery into a backup power when the power grid is not operated normally.

Abstract: A distributed power supply system includes a plurality of energy modules, a plurality of power conversion modules, and a bus voltage controller. The energy modules are electrically connected to a DC bus via corresponding power conversion modules, and the bus voltage controller is connected to the power conversion modules. An energy regulation method includes: acquiring at least one energy state parameter of the corresponding energy module and computing a base value of the respective power conversion module; generating a normalized control signal based on a bus voltage of the DC bus and transmitting the control signal to the power conversion modules by the bus voltage controller; and obtaining a specified control reference value of the power conversion module depending on the control signal and the base value and regulating the corresponding energy module depending on the specified control reference value by the power conversion module.

Abstract: A photovoltaic energy storage system includes an energy storage device, an inverter, a photovoltaic array device, a DC/DC conversion device and a controller. When an output voltage of the photovoltaic array device is greater than or equal to a predetermined threshold value, the photovoltaic energy storage system is operated in a first working mode. When the output voltage of the photovoltaic array device is lower than the predetermined threshold value, the photovoltaic energy storage system is operated in a second working mode. The DC/DC conversion device includes a bypass switch and a DC/DC converter. When the photovoltaic energy storage system is operated in the second working mode, the bypass switch is turned on and the DC/DC converter is disabled. Consequently, the electric power of the energy storage device is transmitted to the inverter through the bypass switch.

Abstract: A wind power converting device includes a plurality of grid-side converters, a plurality of generator-side converters and a plurality of DC buses. The grid-side converters are connected with each other in series and electrically coupled to a power grid. The generator-side converters are connected with each other in series and electrically coupled to a generator device. The DC buses are electrically coupled between the grid-side converters and the generator-side converters. The DC buses include a positive DC bus, a negative DC bus and at least one intermediate DC bus between the positive DC bus and the negative DC bus. A cross section area of a conductor of the intermediate DC bus is smaller than 30% of a cross section area of a conductor of the positive DC bus or smaller than 30% of a cross section area of a conductor of the negative DC bus.

Abstract: The present application provides a monitoring and protection system and an energy storage device. The monitoring and protection system is applied to at least one battery module and includes a temperature monitoring apparatus, a deformation monitoring apparatus, and a control apparatus. The temperature monitoring apparatus includes a plurality of grating temperature sensors, and each grating temperature sensor is arranged on a corresponding battery module to obtain a current temperature of the battery module. The deformation monitoring apparatus obtains a current deformation amount of each battery module, and includes a plurality of grating strain sensors, and each grating strain sensor are arranged on a corresponding battery module. The control apparatus controls a protective unit to perform a corresponding protective action according to the current temperature and current deformation amount.

Abstract: A photovoltaic energy storage system includes an energy storage device, an inverter, a photovoltaic array device, a DC/DC conversion device and a controller. When an output voltage of the photovoltaic array device is greater than or equal to a predetermined threshold value, the photovoltaic energy storage system is operated in a first working mode. When the output voltage of the photovoltaic array device is lower than the predetermined threshold value, the photovoltaic energy storage system is operated in a second working mode. The DC/DC conversion device includes a bypass switch and a DC/DC converter. When the photovoltaic energy storage system is operated in the second working mode, the bypass switch is turned on and the DC/DC converter is disabled. Consequently, the electric power of the energy storage device is transmitted to the inverter through the bypass switch.

Abstract: The application discloses a power conversion system and a controlling method of the same. The power conversion system includes: n choppers, comprising n switching arms connected in parallel, each chopper including: the switching arm, an inductor having a first end connected to a midpoint of the switching arm, and a first capacitor connected in parallel to the switching arm; and n DC components corresponding to the n choppers with a one-to-one relation, wherein one of the DC components is a DC power supply or a DC load, first ends of the DC components are connected together, and a second end of each of the DC components is connected to a second ends of the inductor of the corresponding chopper, where n is a natural number of 2 or more.

Abstract: An energy storage device for a power system is provided. The energy storage device is electrically connected with a high voltage DC transmission grid. The energy storage device includes at least one energy storage element, at least one bidirectional inverter module, at least one medium frequency transformer and at least one bidirectional AC/DC conversion module. A DC terminal of each bidirectional inverter module is electrically connected with the corresponding energy storage element. A first transmission terminal of each medium frequency transformer is electrically connected with an AC terminal of the corresponding bidirectional inverter module. An AC terminal of each bidirectional AC/DC conversion module is electrically connected with a second transmission terminal of the corresponding medium frequency transformer. A DC terminal of each bidirectional AC/DC conversion module is electrically connected with the high voltage DC transmission grid.

Abstract: The present disclosure provides a power supply system method for an AC load. The system includes a power supply device and a DC/AC converter. An AC side of the DC/AC converter is coupled to an AC grid and the AC load through an AC bus. The power supply device outputs DC electric energy and is coupled to a DC side of the DC/AC converter through a DC bus. The power supply device includes an energy storage circuit and a controller. The energy storage circuit includes a first energy storage circuitry and a second energy storage circuitry. The controller is configured to control a conversion operation of the first energy storage circuitry to output a low-frequency power to the DC bus, and a conversion operation of the second energy storage circuitry to output a high-frequency power to the DC bus.

Abstract: The present disclosure provides a three-phase AC system and a control method thereof. The method includes: receiving an output signal of the three-phase AC system and obtaining a characteristic value of the output signal according to the output signal; performing virtual synchronous generator control on the inverter to obtain a fundamental electric potential; extracting a harmonic component from the output signal and obtaining an error signal according to the harmonic component and a reference value of the harmonic component; controlling the error signal to obtain a harmonic compensation electric potential; obtaining a control electric potential by superimposing the harmonic compensation electric potential with the fundamental electric potential; obtaining a pulse signal by modulating the control electric potential, and obtaining a switching signal of the inverter according to the pulse signal.

Abstract: The present disclosure provides an islanding detection method for an inverter and a corresponding apparatus. The islanding detection method includes: step A1: obtaining a parameter of an output voltage of a three-phase AC system and a steady-state value corresponding to the parameter within a period of time; step A2: obtaining a disturbance signal based on the parameter and the steady-state value; step A3: superimposing the disturbance signal on at least one reference value of a droop control; and step A4: detecting the parameter added with the disturbance signal, and determining that island occurs in response to the parameter greater than an upper limit or less than a lower limit.

Abstract: The application relates to battery internal resistance detection device and method for power conversion device. The detection device includes a data acquisition module for acquiring a battery voltage and a battery current to obtain a DC voltage, an AC voltage, a DC current and an AC current, a first calculation module for receiving the AC current and the AC voltage at a certain instant to output a first internal resistance value and a battery capacitance, a second calculation module for receiving a plurality of DC currents and a plurality of DC voltages at multiple instants and the battery capacitance to output a second internal resistance value, and a selection module for receiving the first and second internal resistance value and selecting one of the first and second internal resistance value as battery internal resistance value. The application improves detection accuracy of battery internal resistance by combining DC and AC algorithms.

Abstract: A distributed power supply system includes a plurality of energy modules, a plurality of power conversion modules, and a bus voltage controller. The energy modules are electrically connected to a DC bus via corresponding power conversion modules, and the bus voltage controller is connected to the power conversion modules. An energy regulation method includes: acquiring at least one energy state parameter of the corresponding energy module and computing a base value of the respective power conversion module; generating a normalized control signal based on a bus voltage of the DC bus and transmitting the control signal to the power conversion modules by the bus voltage controller; and obtaining a specified control reference value of the power conversion module depending on the control signal and the base value and regulating the corresponding energy module depending on the specified control reference value by the power conversion module.