Abstract: A power supply system includes direct current combiner boxes and an inverter, where output terminals of all direct current combiner boxes are connected in series and/or in parallel and then coupled to an input terminal of the inverter, and the direct current combiner box includes a controller, a detection circuit, and a direct current conversion circuit. The direct current conversion circuit performs direct current conversion on an input terminal voltage of the direct current combiner box to obtain an output terminal voltage of the direct current combiner box. The detection circuit detects an output terminal parameter of the direct current combiner box, and sends the output terminal parameter of the direct current combiner box to the controller. The controller controls an output voltage of the direct current conversion circuit based on the output terminal parameter of the direct current combiner box.

Abstract: A circuit breaker includes a mechanical switch circuit, and the mechanical switch circuit includes a busbar, a power module, and a drive module. The power module includes a movable contact and a stationary contact that is electrically connected to the busbar. When the movable contact is connected to the stationary contact, the mechanical switch circuit is connected. The drive module includes a switch circuit, a movable coil, and a stationary coil. The movable coil and the stationary coil are disposed adjacently, the switch circuit is configured to control a current direction of the movable coil and a current direction of the stationary coil, and the movable coil and the stationary coil attract or repel each other based on whether the current directions are the same to enable the movable coil to drive the movable contact to be connected to or disconnected from the stationary contact.

Abstract: An energy storage system, a battery monitoring method, and an energy storage device, to improve precision and stability of the energy storage system. The system includes: a battery module, a temperature sensor, and a battery monitoring unit. The battery module includes at least two battery areas. The temperature sensor is disposed in each battery area. The battery monitoring unit determines, based on a plurality of temperature signals sent by temperature sensors, a first battery area corresponding to an abnormal temperature signal that reaches a first preset temperature threshold. When an adjacent temperature signal of a second battery area that is connected to the first battery area is greater than a second preset temperature threshold, rated power of the battery module is reduced.

Abstract: A wireless charger includes an upper housing assembly, a lower housing assembly, a magnetic sheet coil, and a heat dissipation ring. A concave structure is provided on an upper surface of the lower housing assembly, and the concave structure is coupled to the upper housing assembly to form a cavity structure. The cavity structure accommodates the magnetic sheet coil and the heat dissipation ring. The heat dissipation ring is embedded in the magnetic sheet coil and is in contact with the magnetic sheet coil. An upper surface of the heat dissipation ring is coupled to the upper housing assembly. A lower surface of the heat dissipation ring is coupled to a bottom of the concave structure of the lower housing assembly. The heat dissipation ring may transfer heat in the upper housing assembly to the bottom of the lower housing assembly.

Abstract: A method for controlling a totem-pole PFC circuit. When an alternating current of an input end of a totem-pole PFC circuit is in a positive half period, if a previous switching period is less than specified duration, after charging of a PFC inductor is completed, a switch that enables the PFC inductor to be discharged is first delayed for specified threshold duration, and then the switch that enables the PFC inductor to be discharged is turned on, so that the switch that enables the PFC inductor to be discharged is turned on only once. In an existing PFC application, when an input voltage is in a positive half period, a switch that enables a PFC inductor to be discharged needs to be turned on twice.

Abstract: A protection apparatus includes an interface, a protection switch, a direct current bus, and a controller. The apparatus is connected to at least two photovoltaic units via the interface, the at least two photovoltaic units are coupled to the direct current bus inside the apparatus to form at least two branches, and each branch is connected to at least one photovoltaic unit. The protection switch is configured to disconnect all or some of the photovoltaic units from the direct current bus, to enable a maximum of three photovoltaic units to be directly connected in parallel. According to the apparatus, a photovoltaic unit and a line are protected with a low power loss when a photovoltaic power generation system is faulty.

Abstract: A wireless charging receiving apparatus of a mobile terminal. The wireless charging receiving apparatus is configured to be disposed inside the mobile terminal and close to a metal rear housing of the mobile terminal, and includes two interconnected coils. The two coils are located in a same plane and are connected in series, and winding directions of the two coils are opposite, so that directions of magnetic fluxes generated by the two coils on the metal rear housing are opposite, thereby resolving a problem of an eddy current on the metal rear housing of the mobile terminal such as a smartphone including a wireless charging system, and reducing a temperature of a metal body and reducing an energy loss without forming a hole or a seam on the metal rear housing.

Abstract: A DC-DC converter includes: a first capacitor, a second capacitor, a first switch device, a second switch device, a third switch device, a fourth switch device, a flying capacitor, where one end of the flying capacitor is coupled to the first intermediate node, the other end of the flying capacitor is coupled the second intermediate node; and the protective circuit, including a clamping unit and a buffering unit, where when a voltage between the positive end of the bus and the negative end of the bus increases, the clamping unit clamps the first switch device to a voltage of the first capacitor, and clamps the fourth switch device to a voltage of the second capacitor, and the buffering unit reduces a current flowing through the clamping unit and the flying capacitor.

Abstract: An electric drive system and a heating method. The electric drive system includes an inverter circuit, a direct current-direct current conversion circuit, and a controller. An input end of the inverter circuit is connected to an input end of the electric drive system, and an output end of the inverter circuit is connected to three-phase motor windings of an electric excitation synchronous motor. An input end of the direct current-direct current conversion circuit is connected to the input end of the electric drive system, and an output end of the direct current-direct current conversion circuit is connected to an excitation winding of the electric excitation synchronous motor. In this solution, a heating apparatus does not need to be disposed when the power battery pack is heated, thereby reducing costs and saving space.

Abstract: A charger, a soft-start method, an electric vehicle, and a charging system. The charger includes a control module, a DC-DC conversion circuit, and a first capacitor. When the electric vehicle is charged, the control module in the charger may first control the DC-DC conversion circuit to charge the first capacitor by using battery electric energy output by a battery system, and after determining that a capacitance voltage of the first capacitor reaches a first threshold voltage, indicate a charging pile to output charging electric energy. A soft-start circuit does not need to be disposed in a soft-start process of the charger, which helps simplify a circuit of the charger and implement a miniaturization design of the charger.

Abstract: An isolated bidirectional active-half-bridge resonant DC-DC power conversion apparatus employs dual control strategies to regulate bi-directional power flow between two DC sources. The apparatus includes a first half bridge switching network configured to convert a first DC power to an AC power. A series resonant impedance transfers the AC power to a first winding of a transformer. A first inductor and a second inductor are connected in series across a second winding of the transformer and form a positive DC node. A second half bridge switching network is connected in parallel with a first clamping capacitor, with a central node connected to the first end of the second winding. A third half bridge switching network is connected in parallel with a second clamping capacitor, with a central node connected with the second end of the second winding. The clamping capacitors are connected with a negative DC node.

Abstract: A heat exchanger includes a vapor collection pipe, a liquid collection pipe, and an exchange pipeline. The exchange pipeline includes a condensing section, an evaporation section, and a transition section. An upper end of the condensing section is connected to the vapor collection pipe. A lower end of the condensing section is connected to a first end of the transition section. An upper end of the evaporation section is connected to a second end of the transition section. A lower end of the evaporation section is connected to the liquid collection pipe. The evaporation section and the condensing section respectively extend in directions opposite to each other.

Abstract: Embodiments of this application provide a motor rotor, a motor, and a vehicle. A conductive pillar passes through an inner ring of a conductive bearing, an outer wall of the conductive pillar interference fits with the inner ring of the conductive bearing, and an end of the conductive pillar is grounded. In this way, it is ensured that a shaft current on a rotor body is discharged by using the conductive bearing and the conductive pillar, to prevent a main bearing of the motor rotor from being electrically corroded by the shaft current. In addition, the conductive bearing is sleeved on the grounded conductive pillar, so that the inner ring of the conductive bearing can interference fit with the outer wall of the conductive pillar.

Abstract: A photovoltaic system includes an inverter, a controller, and at least two converters. An input terminal of each of the at least two converters are connected to a corresponding photovoltaic module, and output terminals of the at least two converters are connected in series and connected to an input terminal of the inverter. The controller is configured to set a voltage limiting value of at least one of the at least two converters, so that an output voltage of the at least one converter is less than or equal to the voltage limiting value when the converter works in a voltage limiting mode. The voltage limiting value of the at least one converter is proportional to an open circuit voltage of the photovoltaic module connected to an input terminal of the converter. Open circuit voltages of different photovoltaic modules vary with different parameters or models of the photovoltaic modules.

Abstract: A plug status detection circuit, a controller, and a vehicle are provided, to detect a plug status in different standards by using one detection circuit. The plug status detection circuit includes a wake-up circuit and a sampling circuit. The wake-up circuit is configured to immediately output or delay outputting a wake-up signal based on a resistance value of a connected resistor of the plug status detection circuit when a plug is connected to a socket, where the wake-up signal is used to trigger a CPU to drive the sampling circuit. The sampling circuit is configured to inject a startup voltage under the drive of the CPU, and after the startup voltage is injected, a level of a detection point of the sampling circuit is used to indicate a plug status.

Abstract: A distributed power supply system and a control method. The system includes a battery management system and M battery units, where the battery unit includes a battery management unit and a cell. The battery management system is configured to communicate with the M battery management units to obtain M pieces of state information and send an instruction to a target battery management unit in the M battery management units based on the M pieces of state information. The target battery management unit is configured to control, according to the instruction, voltage balancing for a battery unit in which the target battery unit is located.

Abstract: A three-level neutral point clamped inverter includes four switch units. When an average value of an output current of the three-level neutral point clamped inverter is greater than a first current threshold or less than a second current threshold, only one of the four switch units is controlled to perform a high-frequency operation, to reduce power consumption caused by a high-frequency operation. The average value of the output current is an average value of the output current of the three-level neutral point clamped inverter in a switching cycle. The first current threshold is a positive number, and the second current threshold is a negative number. Power consumption caused by the high-frequency operation of the switch unit in the inverter may be reduced, and electric energy conversion efficiency of the inverter may be improved. A time period in which two switch units perform complementary operations at high frequency is very small.

Abstract: A lightning protection apparatus disposed in a photovoltaic power generation system includes first lightning protection units in a one-to-one correspondence with phase lines at a to-be-protected location in the photovoltaic power generation system and a second lightning protection unit connected in series to the first lightning protection units. A first terminal of each first lightning protection unit is connected to a corresponding to-be-protected phase line, and a second terminal of each first lightning protection unit is connected to a first terminal of the second lightning protection unit. A second terminal of the second lightning protection unit is connected to an earth wire. The second lightning protection unit includes at least one gas discharge tube.

Abstract: A photovoltaic inverter is provided, including an inverter circuit, a data sampling module, and a control module. The inverter circuit includes a switch component and an alternating current output terminal. The data sampling module is configured to collect, from the alternating current output terminal, an instantaneous current value at each sampling point moment in target sampling duration and an instantaneous value of each-phase current at a target moment. The control module is configured to: determine a valid current value of the target sampling duration based on the instantaneous current value at each sampling point moment, determine an upper switching frequency limit and a lower switching frequency limit of an Nth switching period based on the valid current value, and determine a target instantaneous current value IN based on the instantaneous value of each-phase current at the target moment.

Abstract: A photovoltaic energy system and a method for detecting a ground insulation impedance, improve accuracy of detecting a ground insulation impedance after one or more conversion circuits are connected in parallel. The photovoltaic energy system includes one or more conversion circuits and a detection circuit. The detection circuit includes an alternating current signal source and a sampling resistor that are connected in series, a first sampling circuit, and a control circuit. The control circuit is configured to control the alternating current signal source to output harmonic signals of a first frequency and a second frequency. The first sampling circuit is configured to: when the alternating current signal source outputs the harmonic signal of the first frequency, collect a voltage at both terminals of the sampling resistor to obtain a first voltage.