Abstract: This application provides a resonant conversion system, including a controller and a resonant conversion circuit. The resonant conversion circuit includes a high frequency chopper circuit, a resonant cavity, a transformer, and a rectification filter network, and the high frequency chopper circuit includes switches S1 and S2. The controller is configured to: detect a bridge arm midpoint voltage VSW, and determine based on the VSW a current threshold signal used to indicate a current threshold; detect a resonant current on a primary side of the transformer, and compare the resonant current with the current threshold signal to control on/off of the switch S1 or S2 based on the second electrical signal, so that the system operates in an inductive mode to ensure zero voltage switching of the switch, while operating in a state close to a capacitive mode to maximize the use of a gain region.

Abstract: A breaker apparatus and an inverter system are configured to disconnect an electrical connection when a fault occurs in a protected circuit. The breaker apparatus is connected in series in a protected circuit, and is configured to disconnect the electrical connection when a fault occurs in the protected circuit. The breaker apparatus includes a first branch, and a second branch. The first branch includes an overcurrent-automatic-disconnection unit and a first current limiting unit that are connected in series, where the overcurrent-automatic-disconnection unit is configured to be automatically disconnected when a current flowing through the overcurrent-automatic-disconnection unit exceeds a breaking current threshold. The a second branch is configured to be open or closed under control of the controller.

Abstract: A converter system includes a plurality of converters, a sampling circuit, and a control circuit. The plurality of converters are connected in parallel. Each converter includes a detection circuit which includes a first switch and at least two resistors. The first switch is connected in parallel with one of the at least two resistors. The control circuit control the sampling circuit to collect a first voltage and a second voltage, where the first voltage is a voltage that is between a second bus and a ground cable and that is collected by the sampling circuit when first switches in detection circuits of a first quantity are in a turn-on state, the second voltage is a voltage that is between the second bus and the ground cable and that is collected by the sampling circuit when first switches in detection circuits of a second quantity are in a turn-on state.

Abstract: A battery pack including fire extinguishing equipment. The fire extinguishing equipment includes a first chamber, a second chamber, and an activation line. The first chamber stores a fire extinguishing chemical agent, the second chamber stores a gas-generating chemical agent, and the activation line extends into the second chamber to be in contact with the gas-generating chemical agent. The second chamber includes a pressure relief opening, and the pressure relief opening is in communication with the first chamber, and is configured to spray the gas in the second chamber to the first chamber. The first chamber includes a discharge opening, and the discharge opening is configured to discharge the fire extinguishing chemical agent in the first chamber after the gas generated after the gas-generating chemical agent is ignited enters the first chamber.

Abstract: A bonding structure and a power device. The bonding structure includes a first power unit and at least two bonding wires. At least one end of the bonding wire is connected to the first power unit through bonding. Projections that are of lead paths of the at least two bonding wires and that are on a preset plane have at least one intersection point. Spatial cross wire bonding is performed on the bonding wires, so that lead paths of the bonding wires form an angle with each other, thereby weakening electromagnetic force between the bonding wires. Therefore, fatigue due to fluctuating stress of the bonding wires can be alleviated, service lives of the bonding wires can be prolonged, and bonding effect can be ensured to a maximum extent.

Abstract: A charging apparatus, a charging pile, and a charging system. The charging apparatus includes a positive bus, a negative bus, a DC/DC conversion circuit, and a soft-start circuit. The soft-start circuit is connected to an input end of the DC/DC conversion circuit through the positive bus and the negative bus, and the input end of the DC/DC conversion circuit is connected to a photovoltaic apparatus or an energy storage apparatus through the positive bus and the negative bus. Therefore, when a first voltage between the positive bus and the negative bus is greater than or equal to a first threshold, the DC/DC conversion circuit may perform power conversion on a second voltage received from the photovoltaic apparatus or the energy storage apparatus, and output the second voltage obtained after power conversion.

Abstract: This application provides a two-speed transmission system. The two-speed transmission system includes a first fixed gear fastened on a first shaft, a first floating gear connected to a second shaft through rotation, a first connection mechanism, and a one-way clutch. The first connection mechanism is configured to implement connection or disconnection between the first floating gear and the second shaft. The one-way clutch is located between the first floating gear and the first connection mechanism. An inner surface of the one-way clutch is connected to the first floating gear. An outer surface of the one-way clutch abuts against the first connection mechanism. The outer surface of the one-way clutch is connected to the first connection mechanism. An acting force of the outer surface directly acts on the first connection mechanism instead of a tooth surface of the first floating gear, to reduce an impact on accuracy of gear transmission.

Abstract: A charging module and a charging device. The charging module includes a three-phase rectifier module, a bus capacitor module, an inductor, and a controller. An input end of the three-phase rectifier module is electrically connected to an input power supply, and an output end of the three-phase rectifier module is electrically connected to an input end of the bus capacitor module. The bus capacitor module includes a first bus capacitor and a second bus capacitor. The first bus capacitor is connected between a first output end of a three-phase bridge arm and a midpoint of the three-phase bridge arm, and the second bus capacitor is electrically connected between a second output end of the three-phase bridge arm and the midpoint. The inductor is electrically connected to the midpoint of the three-phase bridge arm and a midpoint between the first bus capacitor and the second bus capacitor.

Abstract: A resonant converter, a control method of a resonant converter, and a related device. The resonant converter includes a control circuit, a drive circuit, and a switch circuit. The control circuit is configured to generate, based on a target output electrical parameter of the resonant converter, a first pulse signal and a second pulse signal that have different frequencies. The control circuit is further configured to: obtain a first drive signal based on the first pulse signal and the second pulse signal and send the first drive signal to the drive circuit. The drive circuit is configured to: convert the first drive signal into one or more second drive signals and send the one or more second drive signals to the switch circuit, to turn on or off a switch component in the switch circuit.

Abstract: This application provides a power supply system and a conversion method. The power supply system includes a power generation apparatus, a converter circuit, and a drive control circuit. The drive control circuit may be configured to: when a power grid fails, control, based on duration of previous low voltage ride-through, the converter circuit to increase a value of a current to be output to the power grid from a first operating current value to a low voltage ride-through current value, to increase a voltage value at an output end of the converter circuit. Herein, the previous low voltage ride-through is latest low voltage ride-through. In this application, the system can control, based on duration of previous voltage ride-through, a current to be output by the converter circuit to the power grid, to reduce circuit oscillation, with a simple structure, a simple control method, and high safety.

Abstract: This disclosure provides an energy storage apparatus, an energy storage apparatus control method, and a photovoltaic system. The energy storage apparatus includes: a plurality of battery clusters, a plurality of conversion units, a start unit, and a controller. The controller includes a plurality of control units. The start unit is configured to: after receiving a start signal, control a control switch in at least one battery cluster to close, to start a control unit corresponding to the battery cluster. The control unit is configured to: determine, based on a state of the control switch in the battery cluster, whether a black start mode is on; and when determining that the black start mode is on, control a DC-DC converter in the corresponding conversion unit to release electric energy stored in a battery pack in the corresponding battery cluster, to energize a direct current bus.

Abstract: A battery system is provided, including a processing module and a plurality of battery modules. Each of the plurality of battery modules includes a battery management system and an electrochemical cell pack controlled by the battery management system. The processing module is configured to control the electrochemical cell pack to alternately perform a discharging or charging operation. A sum of power of battery modules other than a first battery module in the plurality of battery modules is greater than power required by a target power-supplied object, and the first battery module is any one of the plurality of battery modules. A battery management system is configured to record a target time. The processing module or the battery management system is configured to determine a state of health of the electrochemical cell pack in the first battery module based on the target time.

Abstract: The photovoltaic system includes an inverter, a fan, and a controller. A photovoltaic string and a direct current bus capacitor are connected between a positive input end and negative input end of the inverter. The controller receives a fast shutdown instruction and sends a drive signal to a switching transistor in the inverter, so that the switching transistor performs a switching action under the action of the drive signal, and the switching transistor consumes electric energy during the switching action; or the controller turns on the fan after receiving the fast shutdown instruction to consume electric energy by using the fan; or the controller may send the drive signal to the switching transistor and also control the fan to be turned on, so that both the switching transistor and the fan consume electric energy.

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: A powertrain system and an electric vehicle to reduce a structure size of the powertrain system. The powertrain system includes two subsystems. The two subsystems are disposed side by side in a first direction and are symmetrical to each other. Each of the subsystems includes a motor, a deceleration mechanism, and an output shaft. A rotation shaft of the motor is disposed in a second direction. The deceleration mechanism includes a cylindrical gear pair and a bevel gear pair. The cylindrical gear pair includes an active cylindrical gear and a driven cylindrical gear, and the active cylindrical gear is connected to the rotation shaft of the motor. The driven cylindrical gear is located on a side that is of the active cylindrical gear and that is away or distal from the other subsystem. The bevel gear pair includes an active bevel gear and a driven bevel gear.

Abstract: A powertrain, a control method, and a hybrid electric vehicle. The powertrain includes a motor controller unit and a motor. The motor controller unit includes N bridge arms, and the motor includes N motor windings corresponding to the N bridge arms. Each of the N bridge arms includes a first end and a second end, the first end of each bridge arm is connected to a positive bus, the second end of each bridge arm is connected to a negative bus, a midpoint of each bridge arm is connected to one end of one motor winding, the other end of each of the N motor windings is connected to one end of a power battery, and the other end of the power battery is connected to the positive bus or the negative bus.

Abstract: A data processing system in the power station operation and maintenance system may determine a faulty module and a normal module based on module data of each photovoltaic module in a photovoltaic string, and obtain first power generation data of the faulty module and second power generation data of the normal module. Further, the data processing system may determine an annual lost energy yield of the faulty module based on the first power generation data, the second power generation data, and a preset energy yield of the photovoltaic power station, and obtain a target operation and maintenance measure from a plurality of operation and maintenance measures based on the annual lost energy yield. In this case, a communication system in the power station operation and maintenance system may notify an operation and maintenance user of the photovoltaic power station to perform operation and maintenance on the faulty module.

Abstract: A variable flux permanent-magnet synchronous motor, a powertrain, and a fan are disclosed, which are applied to the field of motors. The variable flux permanent-magnet synchronous motor includes a stator system 10, a rotor system 20, and a variable magnet system 30. The variable magnet system 30 is located in the stator system 10 or the rotor system 20. The rotor system 20 includes a first permanent magnet 201. The variable magnet system 30 includes a second permanent magnet 301 and a heating apparatus 302. Coercive force of the second permanent magnet 301 is lower than coercive force of the first permanent magnet 201. The heating apparatus 302 is configured to heat the second permanent magnet 301, so that the second permanent magnet 301 has variable flux in a magnetic field.

Abstract: A power distribution subrack and power distribution equipment, and is related to the field of circuit technologies. The power distribution subrack includes a subrack body and a collection board, the collection board is disposed inside the subrack body, and the collection board includes a plurality of connection terminals and a plurality of controllers. Second ends of at least two of the plurality of connection terminals are connected to a same controller. First ends of at least some of the plurality of connection terminals are plug-connected to jacks of one or more circuit breakers, and the at least some connection terminals are in a one-to-one correspondence with the one or more circuit breakers. Each of the at least some connection terminals obtains a status signal of a corresponding circuit breaker, and transmits the status signal to a corresponding controller.

Abstract: A photovoltaic system includes at least one first direct current module, an electromagnetic apparatus, a direct current switch-on/off apparatus, and a second direct current module. First connection ends of all first direct current modules in the at least one first direct current module are connected in parallel and then connected to a first connection end of the electromagnetic apparatus, a second connection end and a third connection end of the electromagnetic apparatus are connected to a first connection end of the second direct current module by using the direct current switch-on/off apparatus, and second connection ends of all the first direct current modules are connected in parallel and then connected to a second connection end of the second direct current module. The electromagnetic apparatus is configured to control the direct current switch-on/off apparatus to disconnect a loop between each first direct current module and the second direct current module.