Abstract: A photovoltaic power generation system includes a single-stage inverter, an anti-backflow circuit, a photovoltaic string, and a coupling capacitor. The anti-backflow circuit is connected to one input end of the single-stage inverter, one output end of the photovoltaic string is connected to the other input end of the single-stage inverter, and the other output end of the photovoltaic string is connected to the anti-backflow circuit. The photovoltaic string includes a buck optimizer and a photovoltaic panel. The anti-backflow circuit is configured to prevent a backflow current from flowing back to the photovoltaic string. The coupling capacitor is connected in parallel to two ends of the anti-backflow circuit and is configured to transmit a signal between each buck optimizer in the photovoltaic string and the single-stage inverter, to control backflow of the backflow current when the anti-backflow circuit fails.

Abstract: A current detection system, a current detection method, and a detection apparatus are provided. The current detection system includes a printed circuit board and N groups of amplification apparatuses, wherein N is a positive integer greater than or equal to 1. Each group includes at least one amplification apparatus. N Rogowski coils are mounted on the printed circuit board. The nth Rogowski coil is capable of being mounted concentric with the nth current-carrying conductor in N current-carrying conductors, which is perpendicular to a plane of the nth Rogowski coil. An output end of the nth Rogowski coil is connected to an input end of the first amplification apparatus in the nth group of the N groups of amplification apparatuses. The foregoing current detection system provides more convenience when being integrated into different electrical equipment, in particular when each group of amplification apparatus includes multiple amplification apparatuses.

Abstract: A gear shifting mechanism includes a drive motor, a shifting drum, and a first shifting mechanism. The first shifting mechanism includes a first shifting fork, an inner shaft, an outer hub, a first coupling pin, and an elastic component. The elastic component is sleeved on the inner shaft and is located between the inner shaft and the outer hub. There is a first limiting portion and a second limiting portion between the outer hub and the inner shaft. The elastic component is located between the first limiting portion and the second limiting portion. The first limiting portion is connected to one of the outer hub and the inner shaft, and the second limiting portion is connected to the other of the outer hub and the inner shaft.

Abstract: A battery module, a battery pack, and a vehicle are described in this patent application. In the battery module, a plurality of grooves separated by partition parts are disposed in a module casing, a plurality of jelly rolls of the battery module are embedded in the grooves, and a top cover covers an opening of each groove to seal the groove as an independent mounting cavity. In this way, each groove wall in the module casing and the top cover may be used as a housing for sealing each jelly roll, to avoid a case in which an electrolyte in each jelly roll decomposes and produces gas in a process of using the battery module because the electrolyte is leaked from one jelly roll to another jelly roll.

Abstract: A reverse power connection preventing circuit includes a diode and an actuation unit that are connected in series between a positive input terminal and a negative input terminal of a circuit breaker. A positive electrode of the diode points to the negative input terminal of the circuit breaker, and a negative electrode of the diode points to the positive input terminal of the circuit breaker. When a power supply is forward connected to the circuit breaker, the diode is cut off, there is no current on the actuation unit, and the reverse power connection preventing circuit is in a power-off state. When the power supply is reversely connected to the circuit breaker, the diode conducts, and the actuation unit is configured to prevent closing of the circuit breaker, and/or the actuation unit is configured to perform an alarm prompt, to perform an early warning.

Abstract: A three-level converter includes a high-voltage side unit, a low-voltage side unit, a flying capacitor, a first switch to a fourth switch, and a control unit. When a voltage of the flying capacitor falls outside a safe target voltage range, the control unit may control the third switch and the fourth switch to be normally open, and control, based on the voltage of the flying capacitor and a voltage of the low-voltage side unit, each of the first switch and the second switch to be turned on or off, so that the voltage of the flying capacitor falls within the target voltage range. Alternatively, the control unit may control the first switch and the second switch to be normally open, and control, based on the voltage of the flying capacitor and a voltage of the low-voltage side unit.

Abstract: An electronic device includes a lower housing and an upper cover that are connected to each other. The upper cover has a bending structure that faces a direction of the lower housing, an end that is of the lower housing and that faces the upper cover has a flanging structure, the flanging structure overlaps a bottom wall of the bending structure, and the upper cover and the lower housing are connected at an overlapping part of the bending structure and the flanging structure.

Abstract: A power conversion apparatus and an energy storage system, including a power conversion circuit, a first power terminal, a second power terminal, and a third power terminal. The power conversion circuit includes a first positive end, a first negative end, a second positive end, a second negative end, and at least one power device. The first negative end and the second negative end have a same potential. The power conversion circuit is configured to convert a first voltage input by a first device into a second voltage and output the second voltage to a second device. The first power terminal is connected to the first positive end, the first negative end or the second negative end is connected to the second power terminal, and the third power terminal is connected to the second positive end.

Abstract: A voltage conversion apparatus, a control method, and a power supply device. The voltage conversion apparatus includes a control circuit. The control circuit is configured to: obtain a first sampling voltage and a second sampling voltage; detect a resonant period based on the second sampling voltage when it is determined, based on the first sampling voltage, that a voltage range of an output voltage of the voltage conversion apparatus changes and a voltage threshold is exceeded; and output a drive signal based on the detected resonant period. The drive signal is used to control turn-on and turn-off of a first switching transistor and a second switching transistor.

Abstract: The embodiments provide an RSCC and a control method thereof. The RSCC includes an input capacitor, an output capacitor, N parallel RSC branches, and a controller. The controller is configured to: determine an average value of characteristic currents of N resonance units; and reduce a duty cycle of a control signal of a charging switch in a first switch unit when determining that a characteristic current of a first resonance unit is greater than the average value, where a corresponding branch is in a charging stage when the charging switch is turned on; or reduce a duty cycle of a control signal of a discharging switch in a first switch unit when determining that a characteristic current of a first resonance unit is less than the average value, where a corresponding branch is in a discharging stage when the discharging switch is turned on.

Abstract: A stator, a motor, and an electric vehicle are provided. The stator includes: a housing, where the housing has an accommodation space, and an oil inlet is disposed on the housing; a ring-shaped iron core punching sheet, where the iron core punching sheet is disposed in the accommodation space, and abuts against an inner wall of the housing; a spacer sleeve, where the spacer sleeve is sleeved in the iron core punching sheet, an outer surface of the spacer sleeve abuts against a side that is of the tooth part and that faces away from the yoke part, and a slot opening of the stator slot fits with the spacer sleeve to form a third cooling channel; and a flow guiding assembly, where the flow guiding assembly is disposed in the accommodation space. The three-layer oil-injection cooling design can improve a heat dissipation capability of the stator.

Abstract: A photovoltaic power generation system and a conversion circuit. Two groups of photovoltaic arrays are cascaded by using the conversion circuit disposed in the photovoltaic power generation system to effectively increase an input voltage of a DC/AC conversion circuit. In this way, a cable with an existing diameter specification can improve current transmission in the photovoltaic power generation system, to effectively reduce costs of the photovoltaic power generation system. A voltage to earth at an intermediate node in the conversion circuit is adjusted to a first preset value, so that both an absolute value of a voltage to earth of a first group of photovoltaic arrays and an absolute value of a voltage to earth of a second group of photovoltaic arrays are less than a first threshold.

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: The control system includes a PFC circuit and a sampling control circuit, and the PFC circuit includes an inductor, a first power supply drive circuit, and a first bridge arm and a second bridge arm that are connected in parallel, and a first bridge arm midpoint is a serial connection point between a first upper bridge arm and a first lower bridge arm of the first bridge arm. The sampling control circuit is configured to control, based on voltages of two ends of an alternating current power supply, the first lower bridge arm to be turned on, so that the first power supply drive circuit starts charging. The sampling control circuit is further configured to: when charging duration of the first power supply drive circuit reaches first target duration, control the first lower bridge arm to be turned off, so that the first power supply drive circuit completes charging.

Abstract: A wireless power supply apparatus includes a controller, a beamforming module, and an antenna array. When direction finding information is obtained, the controller determines an electromagnetic wave transmission direction, and transmits information about the transmission direction to the beamforming module. The beamforming module aggregates energy of electromagnetic waves corresponding to a plurality of radio frequency signals to the transmission direction. The antenna array receives the direction finding information, and transmits the electromagnetic waves.

Abstract: A power module, a totem-pole power factor correction circuit, and a control circuit thereof. In response to a case in which a phase value of a transient voltage of an input voltage of the totem-pole power factor correction circuit is within a predetermined phase range, and an absolute value of a voltage value is less than a predetermined voltage value, the control circuit controls a main power switch in the totem-pole power factor correction circuit to be turned on and off, and controls an auxiliary power switch to remain off.

Abstract: A power supply switching apparatus and a multi-input power supply, which is applicable to the field of power supply technologies. In the solution of the embodiments, a voltage output by a secondary winding of a transformer in a power conversion circuit is reused to provide a working voltage for a multi-input switching relay. Compared with using an additional boost circuit to provide a higher working voltage for the multi-input switching relay, this can reduce an occupied board area, save costs, and reduce control complexity of the power supply switching apparatus.

Abstract: A power supply apparatus includes a totem-pole power factor correction (PFC) circuit and a control apparatus, and the totem-pole PFC circuit includes a first switching transistor and a second switching transistor. The control apparatus includes a controller and a dead time detection circuit, and the dead time detection circuit includes a detection capacitor and a detection resistor. A first end of the detection capacitor is connected to a first reference point, a second end of the detection capacitor is connected to a first end of the detection resistor, and a second end of the detection resistor is grounded. The controller is configured to, respectively, control an on/off status of the first switching transistor and an on/off status of the second switching transistor based on a voltage of the detection resistor and polarity of a voltage input by an alternating current input source.

Abstract: An electronic apparatus and a photovoltaic power optimizer. The electronic apparatus includes a circuit board, a heat dissipation housing, and an insulation member. The circuit board has a first surface and a second surface opposite to each other, where a first heat dissipation region is formed on the first surface and a second heat dissipation region is formed on the second surface. A first heat dissipation member has a first heat dissipation surface that is in direct contact with the first heat dissipation region. A second heat dissipation member is connected to the first heat dissipation member in a first direction, and has a second heat dissipation surface that is in direct contact with the second heat dissipation region. The first heat dissipation region and the second heat dissipation region are sealed by using the first heat dissipation member and the second heat dissipation member.

Abstract: A circuit board assembly includes a circuit board and a conductive plate. The circuit board includes a substrate and a conductive trace. The conductive trace is disposed on the substrate. The conductive plate is fastened in a first region of the circuit board, and a current-carrying capacity of the conductive plate is greater than that of the conductive trace. In the circuit board assembly, the conductive plate capable of carrying a relatively large operating current is provided to significantly improve a current-carrying capability of the circuit board assembly; and the conductive plate and the circuit board are manufactured separately, and then, the conductive plate is disposed in the first region of the circuit board, to implement a fastened connection between the conductive plate and the circuit board. Therefore, manufacturing costs and process difficulty are reduced, and low-cost and batch manufacturing is implemented.