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 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.

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: An apparatus includes a controller configured to generate a PWM signal for controlling a power switch of a forward converter, a bias switch and a bias capacitor connected in series and coupled to a bias winding of the forward converter, and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the bias winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

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: 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 photovoltaic system, a power supply system, and an insulation fault detection method. An insulation impedance detection circuit is connected between a bus and the ground. The bus includes the direct current positive bus, the neutral bus, or the direct current negative bus. The insulation impedance detection circuit includes at least a switch. The direct current negative bus is connected to the neutral bus by using an electrical element or a voltage source. A controller obtains insulation impedance based on voltages to ground of the bus that are separately corresponding to the switch before and after the switch is turned on, and determines, based on the insulation impedance, whether there is an insulation fault in the photovoltaic system, to perform protection in a timely manner.

Abstract: A power supply topology includes a first flyback power supply and a first forward power supply. The first flyback power supply is coupled to a first battery module and is configured to convert a first direct current output by the first battery module into a second direct current, where the second direct current is used to supply power to a lower bridge arm drive circuit in the motor drive controller. The first forward power supply is coupled to the first flyback power supply, and is configured to convert the second direct current into a third direct current, where the third direct current is used to supply power to an upper bridge arm drive circuit. The power supply topology is configured to supply power to the motor drive controller, thereby reducing a size of a transformer, and saving space of the whole vehicle.

Abstract: This application discloses a converter and a power adapter, to reduce an energy loss of the power adapter. The converter includes: a DC power supply, a primary power transistor, an auxiliary power transistor, a first capacitor, a transformer, and a control circuit. The first capacitor is connected in series to the transformer to form a series circuit, the series circuit is connected in parallel to a first terminal and a second terminal of the auxiliary power transistor. The control circuit is configured to: when an excitation current in the transformer is in a continuous state, regulate a target voltage to a preset voltage threshold, and control the primary power transistor to be turned on when first dead time ends, where the target voltage is a voltage between the first terminal of the primary power transistor and the ground.