Abstract: A system for controlling a direct current bus voltage includes a controller and an inverter. The controller is configured to: obtain a power grid voltage; obtain a maximum sampling value of a direct current bus voltage of the inverter when the power grid voltage jumps, where the maximum sampling value of the direct current bus voltage is a maximum voltage value on the direct current bus in a time period for detecting a power grid voltage jump; obtain a first direct current bus voltage reference value based on the maximum sampling value of the direct current bus voltage; and obtain a second direct current bus voltage reference value based on the first direct current bus voltage reference value and a preset first rising gradient value, to limit a rising rate of the direct current bus voltage.

Abstract: Provided are a method for service status analysis, a server, and a storage medium. The method includes: for each vertex of multiple vertices in a graph database: reading out attribute data of the vertex, where the graph database is generated in advance according to a service description table, the vertex represents a service, and the attribute data of the vertex includes at least one service attribute of the service represented by the vertex; and according to the attribute data of the vertex and attribute data of each of multiple related vertices, determining a service status level of the service represented by the vertex, where each of the multiple related vertices has a propagation relationship with the vertex; and according to the service status level of each of the services represented by the vertices, analyzing a service propagation network.

Abstract: Providing heteraromatic compounds and uses thereof. In particular, providing heteraromatic compounds of formula (I), pharmaceutical compositions comprising same, methods for preparing same and uses thereof, wherein the variables are as defined in the description.

Abstract: This application provides a photovoltaic energy storage control module and a photovoltaic energy storage control method. A control component included in the photovoltaic energy storage control module can set reference values of bus voltages of a first direct-current converter, a second direct-current converter, and an inverter. Further, the first direct-current converter, the second direct-current converter, and the inverter can automatically adjust a power supply relationship among the first direct-current converter, the second direct-current converter, and the inverter based on a value relationship among the reference values of the bus voltages of the first direct-current converter, the second direct-current converter, and the inverter. In this way, flexibility of the photovoltaic energy storage control module is improved.

Abstract: A continuous operation method is employed for the microwave high-temperature pyrolysis of a solid material containing an organic matter. The method includes the steps of mixing a solid material containing an organic matter with a liquid organic medium; transferring the obtained mixture to a microwave field; and in the microwave field, continuously contacting the mixture with a strong wave absorption material in an inert atmosphere or in vacuum. The strong wave absorption material continuously generates a high temperature under a microwave such that the solid material containing an organic matter and the liquid organic medium are continuously pyrolyzed to implement a continuous operation.

Abstract: A power system includes N direct current coupling units, N direct current buses, and a main controller. The main controller is configured to: obtain a total network input demand power (a network input power required by the power grid); obtain first amplitude limiting values (indicate a maximum discharging power that can be supplied by each energy unit to the power grid); and determine first network input power values (a power value allocated to each energy unit and that is input to the power grid, and at least one direct current coupling unit is in a first amplitude limiting state) based on the total network input demand power and the first amplitude limiting values, and the first amplitude limiting state is that a first network input power value of direct current coupling unit is equal to a first amplitude limiting value corresponding to the direct current coupling unit.

Abstract: A voltage source inverter includes a bus capacitor, a bidirectional power tube, a filter inductor, and a filter capacitor. A voltage control method includes: respectively obtaining a first feedback current and a first feedback voltage from an output end of the filter inductor and an output end of the filter capacitor; obtaining a first duty cycle and a second duty cycle based on the first feedback current, a maximum current reference value, and a minimum current reference value in a current loop; obtaining a third duty cycle based on the first feedback voltage and a voltage reference value in a voltage loop; and selecting one of the first duty cycle, the second duty cycle, and the third duty cycle, and controlling the bidirectional power tube, so that a duty cycle of the bidirectional power tube is between the first duty cycle and the second duty cycle.

Abstract: This application discloses a common-mode voltage adjustment method and apparatus, and a control system, and relates to the field of electronic technologies. In an example method, a controller generates an injection instruction of a first common-mode voltage based on a first modulation scheme, generates an injection instruction of a second common-mode voltage based on a second modulation scheme, and generates an injection instruction of a third common-mode voltage based on the injection instruction of the first common-mode voltage and the injection instruction of the second common-mode voltage during a modulation scheme switching period. The injection instruction of the third common-mode voltage may be used to control a inverter circuit to output the third common-mode voltage.

Abstract: A power supply system and an IV curve scanning method for a power supply system. The power supply system includes at least a first inverter and a second inverter. The first inverter starts, at an IV curve scanning start time of the first inverter, to perform IV curve scanning on a string connected to the first inverter, and the second inverter starts, at an IV curve scanning start time of the second inverter, to perform IV curve scanning on a string connected to the second inverter. Their IV curve scanning start time is different. In addition, a time interval between the IV curve scanning their start time is less than a preset IV curve scanning period. In the embodiments, fluctuation of an output power of the power supply system during IV curve scanning can be reduced, thereby improving system stability of the power supply system.

Abstract: A power conversion module includes a power transistor and a sampling control unit. The sampling control unit determines a given duty cycle of the power conversion module based on the bus reference duty cycle, the power supply reference duty cycle, and the current limiting reference duty cycle, and controls, based on the given duty cycle, the power transistor to work, to control the direct current bus to have a target bus voltage and enable the power conversion module to run at the maximum power point. In this application, the direct current bus can be stabilized and the power conversion module can be controlled to run at the maximum power point.

Abstract: A photovoltaic system and a leakage current control method for the photovoltaic system includes at least one photovoltaic module group, at least one photovoltaic inverter, a grounded metal frame, and a sampling control unit. The photovoltaic module group is mounted on the grounded metal frame. An output end of the photovoltaic module group is connected to an input end of the photovoltaic inverter, and an output end of the photovoltaic inverter is connected to a power grid. The sampling control unit is coupled to both the photovoltaic module group and the photovoltaic inverter and is configured to detect a current value of a leakage current formed by a common-mode voltage of the photovoltaic inverter on a parasitic capacitor. Herein, the parasitic capacitor exists between the photovoltaic module group and the grounded metal frame.

Abstract: A detection method and a related apparatus. Whether a first converter and a second converter are connected to a same combiner device is determined by determining an output port voltage signal of the first converter and an output port voltage signal of the second converter, so that first information or second information is generated and notified to staff. Generally, if a first converter and a second converter in a combiner system are not connected to a same combiner device, it may be considered as that a wire connection of the first converter or the second converter is incorrect. In the detection method and the related apparatus, whether there is a wiring error in the combiner system of the converters can be quickly and accurately determined in an application scenario in which voltage information at a combiner point cannot be obtained.

Abstract: Example three-level inverters, control methods, and systems are provided. One example three-level inverter includes a first bus capacitor, a second bus capacitor, a power conversion circuit, and a controller. The first bus capacitor is connected in the middle of the current bus and the power conversion circuit. The power conversion circuit is configured to convert a direct current into a three-phase alternating current for output. The controller is configured to determine a balance reference by using a difference between absolute values of voltages of the positive and negative direct current buses and an even harmonic current in a grid-connected current, where the balance reference is used to enable the three-level inverter to generate a current signal for balancing the voltages of the positive and negative direct current buses.

Abstract: A power system includes a controller, configured to adjust an output current of a first converter to a first current value based on a voltage of a direct current bus and a voltage threshold, where a difference between an adjusted voltage of the direct current bus and the voltage threshold is less than a difference between the unadjusted voltage of the direct current bus and the voltage threshold. The controller adjusts the output current of the first converter to a second current value based on output power of the first converter and a power threshold, where a difference between adjusted output power of the first converter and the power threshold is less than a difference between the unadjusted output power of the first converter and the power threshold. The controller adjusts the output current of the first converter based on the first current value and the second current value.

Abstract: A current control method and system for a voltage asymmetry fault is disclosed. When a voltage asymmetry fault occurs, a first current limit value is obtained based on a post-fault positive-sequence voltage and a pre-fault positive-sequence reactive current, and a second current limit value is obtained based on a post-fault negative-sequence voltage and a pre-fault negative-sequence voltage. A third current limit value and a fourth current limit value are obtained based on the first current limit value and the second current limit value. A magnitude of a positive-sequence reactive current is limited by using the third current limit value, and a magnitude of a negative-sequence reactive current is limited by using the fourth current limit value.

Abstract: Embodiments of this application provide a direct current bus voltage control method and apparatus, and a power system, and relate to the field of electric power technologies, to quickly identify a voltage between an inverter circuit and an alternating current grid, so as to timely control a voltage of a direct current bus, thereby improving stability of the power system. The method includes: obtaining an electrical parameter between the conversion circuit and the direct current bus; generating a predicted voltage between the inverter circuit and the alternating current grid based on the electrical parameter and a voltage prediction model; and controlling a voltage between the conversion circuit and the direct current bus based on the predicted voltage.

Abstract: An energy storage system and a control method thereof, so that a voltage level of an energy storage module in the energy storage system can be flexibly matched and the energy storage module can be effectively controlled based on a voltage of a direct current bus, to implement a high response speed. The energy storage system includes a plurality of energy storage modules, and each of the plurality of energy storage modules is connected to the direct current bus. The energy storage module includes a plurality of battery clusters and a plurality of first direct current-direct current converters. The battery cluster is configured to provide a direct current to the first direct current-direct current converter, or store a direct current transmitted by the first direct current-direct current converter.

Abstract: An energy storage system includes a control apparatus and one or more battery sub-arrays. Each battery sub-array includes one or more energy storage racks. Each energy storage rack includes one or more battery packs. The control apparatus is configured to: determine that parameter calibration needs to be performed on a first energy storage rack in a first battery sub-array; when the first energy storage rack meets a preset condition, increase a weight of the first energy storage rack in the first battery sub-array; and after each battery pack in the first energy storage rack is fully charged or remaining power of the battery pack is fully discharged, perform calibration on a parameter of the battery pack.

Abstract: An energy storage system includes N switch units and N battery packs connected in series. The N switch units are separately connected to two ends of the N battery packs in a one-to-one correspondence. Each of the N switch units is configured to: when the energy storage system is in a charging state and remaining power of a battery pack correspondingly connected to each switch unit meets a first preset condition, and/or when the energy storage system is in a discharging state and the remaining power of the battery pack correspondingly connected to each switch unit meets a second preset condition, perform disconnection processing on the battery pack correspondingly connected to each switch unit. The first preset condition includes being greater than or equal to a first preset power value. The second preset condition includes being less than or equal to a second preset power value.

Abstract: A control method of a three-phase multi-level inverter includes: determining a modulation ratio based on output of the three-phase multi-level inverter, where the modulation ratio indicates a ratio of an amplitude value of a sinusoidal modulation wave in pulse width modulation to an amplitude value of a carrier; generating, based on the modulation ratio and a modulation ratio threshold, a common-mode voltage regulation signal for regulating a common-mode voltage in phase voltages of the three-phase multi-level inverter; adding the common-mode voltage regulation signal and a differential-mode voltage regulation signal for regulating a differential-mode voltage in the phase voltages of the three-phase multi-level inverter to obtain a composite regulation signal, where the composite regulation signal is presented as a modulation wave for discontinuous pulse width modulation (DPWM); and generating, based on the composite regulation signal, drive signals for controlling switches of phases of the three-phase multi-