Abstract: The present invention discloses a flue gas low-temperature adsorption denitrification method, including: pressurizing a flue gas that has been subjected to dust removal and desulfurization, precooling the pressurized flue gas, cooling the precooled flue gas to a temperature lower than room temperature by a flue gas cooling system, flowing the flue gas at the temperature lower than room temperature into a low-temperature denitrification system, performing physical adsorption denitrification in the low-temperature denitrification system, precooling the flue gas that has been subjected to dust removal and desulfurization with the denitrificated flue gas, and flowing the heat-absorbed clean flue gas into a chimney to be discharged.

Abstract: The present disclosure provides a control method for a DC converter and a DC converter. the DC converter comprises a switching circuit, a sampling circuit, and a controller, the method comprising: acquiring a duty ratio of a Burst cycle according to an output reference signal and an output signal; acquiring a first number of switching cycles and a burst on time according to the duty ratio of the Burst cycle, a first preset value, and a switching period of the switching device; acquiring a Burst cycle value according to the burst on time and the duty ratio of the Burst cycle; and generating a driving signal according to the Burst cycle value, the first number of switching cycles, and the switching period.

Abstract: An electrical conversion system includes: an inductor electrically connected to an alternating current (AC) power grid; a medium voltage direct current (MVDC) bus; a non-isolated AC/DC converter, provided with a first terminal electrically connected to the inductor and a second terminal electrically connected to the MVDC bus, wherein the non-isolated AC/DC converter is configured to output a bus voltage based on an input voltage from the AC power grid; a plurality of circuit branches connected in parallel, wherein each circuit branch is connected to the MVDC bus via a corresponding converter; and a filtering network disposed between the AC power grid and the MVDC bus and is grounded through at least one capacitor.

Abstract: The present disclosure provides a DC conversion system and a control method thereof. The DC conversion system comprises: an upper power module group, a lower power module group, input terminals of the upper and lower power module group are connected in series, and output terminals of the upper and lower power module groups are connected in parallel; the controller configured to receive an input voltage of respective input terminal of each of the first and second power modules, a first output current of the output terminal of the upper power module group, a second output current of the output terminal of the lower power module group, and a total output signal of the output terminal of the DC conversion system, and generate a modulation signal according to them to control a power switch of the corresponding power module.

Abstract: A conversion device includes: an inductor connected to the AC power grid; a first-stage converter configured to output a bus voltage based on the AC power grid; a second-stage converter configured to convert the bus voltage into an output voltage to the load; and a filtering network, wherein a first resistance-capacitance circuit is disposed between the first and third terminals of the filtering network, a second resistance-capacitance circuit is disposed between the second and third terminals of the filtering network, the first terminal of the filtering network is connected to the AC power grid, the second terminal of the filtering network is connected to the bus or the second terminal of the second-stage converter, and the third terminal of the filtering network is grounded through a first capacitor.

Abstract: A conversion device includes: an inductor electrically connected to the AC power grid; a first-stage converter configured to output a bus voltage according to the AC power grid, wherein the first-stage converter includes an N-level alternating current-direct current (AC-DC) converter, and the N-level AC-DC converter includes a plurality of switch bridge arms, wherein both an upper bridge arm and a lower bridge arm of each of the plurality of switch bridge arms of the N-level AC-DC converter include a plurality of semiconductor devices connected in series, and a rated withstand voltage Vsemi of each of the semiconductor devices is greater than or equal to (Vbus*?)/((N?1)*Nseries*?); and a second-stage converter configured to convert the bus voltage into an output voltage to supply energy to the load.

Abstract: A ground fault detection method for a power converter is provided, including: measuring, by a voltage sensor, a first voltage and a second voltage respectively, and converting the first voltage and the second voltage into a first digital voltage signal and a second digital voltage signal; receiving, by a controller, the first digital voltage signal and the second digital voltage signal, extracting a corresponding feature quantity of the first voltage and a corresponding feature quantity of the second voltage according to the first digital voltage signal and the second digital voltage signal; and further determining a type of the ground fault of the power converter and locating a ground fault; and when the power converter has a ground fault, shutting down the power converter.

Abstract: The present invention relates to the technical field of bee product processing, and discloses a continuous drying apparatus for bee pollen and related drying method. The continuous drying apparatus for bee pollen comprises: a box body; a first drying conveying structure; a second drying conveying structure; and a heat pump dehumidification heating structure. The continuous drying apparatus for bee pollen has the advantage of high drying efficiency.

Abstract: The present disclosure provides a DC conversion system and a control method thereof. The DC conversion system comprises: an upper power module group, a lower power module group, input terminals of the upper and lower power module group are connected in series, and output terminals of the upper and lower power module groups are connected in parallel; the controller configured to receive an input voltage of respective input terminal of each of the first and second power modules, a first output current of the output terminal of the upper power module group, a second output current of the output terminal of the lower power module group, and a total output signal of the output terminal of the DC conversion system, and generate a modulation signal according to them to control a power switch of the corresponding power module.

Abstract: A conversion device includes: an inductor connected to the AC power grid; a first-stage converter configured to output a bus voltage based on the AC power grid; a second-stage converter configured to convert the bus voltage into an output voltage to the load; and a filtering network, wherein a first resistance-capacitance circuit is disposed between the first and third terminals of the filtering network, a second resistance-capacitance circuit is disposed between the second and third terminals of the filtering network, the first terminal of the filtering network is connected to the AC power grid, the second terminal of the filtering network is connected to the bus or the second terminal of the second-stage converter, and the third terminal of the filtering network is grounded through a first capacitor.

Abstract: A conversion device comprises: an inductor electrically connected to the AC power grid; a first-stage converter configured to output a bus voltage according to the AC power grid, wherein the first-stage converter comprises an N-level alternating current-direct current (AC-DC) converter, and the N-level AC-DC converter comprises a plurality of switch bridge arms, wherein both an upper bridge arm and a lower bridge arm of each of the plurality of switch bridge arms of the N-level AC-DC converter include a plurality of semiconductor devices connected in series, and a rated withstand voltage Vsemi of each of the semiconductor devices is greater than or equal to (Vbus*?)/((N?1)*Nseries*?); and a second-stage converter configured to convert the bus voltage into an output voltage to supply energy to the load.

Abstract: The present disclosure provides a control method for a DC converter and a DC converter. the DC converter comprises a switching circuit, a sampling circuit, and a controller, the method comprising: acquiring a duty ratio of a Burst cycle according to an output reference signal and an output signal; acquiring a first number of switching cycles and a burst on time according to the duty ratio of the Burst cycle, a first preset value, and a switching period of the switching device; acquiring a Burst cycle value according to the burst on time and the duty ratio of the Burst cycle; and generating a driving signal according to the Burst cycle value, the first number of switching cycles, and the switching period.

Abstract: The present invention relates to the technical field of bee product processing, and discloses a continuous drying apparatus for bee pollen and related drying method. The continuous drying apparatus for bee pollen comprises: a box body; a first drying conveying structure; a second drying conveying structure; and a heat pump dehumidification heating structure. The continuous drying apparatus for bee pollen has the advantage of high drying efficiency.

Abstract: The present disclosure discloses a method of discharging a bus capacitor in a power converter, the method comprising: outputting a plurality of pulse control signals to the corresponding plurality of power semiconductor switch groups when the working state of the power converter is in a discharge state and the state of the main circuit breaker is open to control the ON and OFF of the plurality of power semiconductor switch groups, respectively, so as to form a discharge loop between the positive terminal and the negative terminal of the bus capacitor within at least a preset time, thereby causing the bus capacitor to discharge. Since a discharge loop is formed by the bus capacitor and the bridge arms and the energy of the bus capacitor is consumed by a power device, thereby the peak value and discharge rate of discharge current can be effectively controlled without adding additional discharge elements.

Abstract: A ground fault detection method for a power converter is provided, including: measuring, by a voltage sensor, a first voltage and a second voltage respectively, and converting the first voltage and the second voltage into a first digital voltage signal and a second digital voltage signal; receiving, by a controller, the first digital voltage signal and the second digital voltage signal, extracting a corresponding feature quantity of the first voltage and a corresponding feature quantity of the second voltage according to the first digital voltage signal and the second digital voltage signal; and further determining a type of the ground fault of the power converter and locating a ground fault; and when the power converter has a ground fault, shutting down the power converter.

Abstract: The present disclosure discloses a method of discharging a bus capacitor in a power converter, the method comprising: outputting a plurality of pulse control signals to the corresponding plurality of power semiconductor switch groups when the working state of the power converter is in a discharge state and the state of the main circuit breaker is open to control the ON and OFF of the plurality of power semiconductor switch groups, respectively, so as to form a discharge loop between the positive terminal and the negative terminal of the bus capacitor within at least a preset time, thereby causing the bus capacitor to discharge. Since a discharge loop is formed by the bus capacitor and the bridge arms and the energy of the bus capacitor is consumed by a power device, thereby the peak value and discharge rate of discharge current can be effectively controlled without adding additional discharge elements.

Abstract: A pig myostatin gene locus and uses thereof are provided. Also provided includes an expression cassette comprising a promoter, a foreign gene and a following terminator; the promoter is a DNA molecule as set forth in any of 1)-4): 1) nucleotides at positions 2642-3778 starting from the 5? end of SEQ ID NO. 1 in the sequence listing; 2) nucleotides as set forth in SEQ ID NO. 1 in the sequence listing; 3) a DNA molecule, hybridizing and having the same function with the DNA sequence as defined in 1) or 2) under stringent condition. Experiments show that the pig myostatin gene locus provides a valuable gene source for gene targeting, as well as introducing and expressing a foreign gene at this site.