Abstract: The present disclosure discloses an onboard power device and a thermal management system, wherein the thermal management system comprises the onboard power device which comprises a power assembly comprising a plurality of electronic components and a shell comprising an inner cavity and a coolant passage that are isolated from each other, wherein the power assembly is disposed in the inner cavity which is filled with insulating heat conductive fluid, the power assembly being immersed in the insulating heat conductive fluid, and wherein a coolant flows through the coolant passage. The present disclosure allows the power assembly to be sufficiently and uniformly cooled by immersing in insulating heat conductive fluid, and by circulating coolant in the coolant passage of the onboard power device.

Abstract: A charging system and a method are provided. The charging system includes a power supply device, a charging module and a battery module. The charging module is detachably connected with the power supply device, and connected with the battery module. The charging module includes a power converting unit, a voltage regulator and a charging controller. When the power supply device and the charging module are connected with each other, the power converting unit of the charging module is in the backward direction and uses the electric power of the battery module to pre-charge a bus capacitor. If the voltage of the bus capacitor is higher than or equal to a first threshold value because of pre-charge, the voltage of an adjusting terminal of the charging module is adjusted. Consequently, the charging system is in a normal working mode.

Abstract: A multi-stage power converter includes a first-stage power conversion circuit, a second-stage power conversion circuit, a second-stage analogic sampler, a pulse width modulator, a first isolator, a pulse width analyzer and a control unit. The second-stage analogic sampler samples power parameter from the second-stage power conversion circuit. The pulse width modulator converts the power parameter into a pulse width modulation signal. The pulse width analyzer receives the pulse width modulation signal through the first isolator in an isolation manner, calculates a duty ratio of the pulse width modulation signal according to a rising edge and a falling edge of the pulse width modulation signal, and calculates the power parameter according to the duty ratio. The control unit controls operations of the second-stage power conversion circuit according to the power parameter that is obtained by the pulse width analyzer.

Abstract: A charging system and a method are provided. The charging system includes a power supply device, a charging module and a battery module. The charging module is detachably connected with the power supply device, and connected with the battery module. The charging module includes a power converting unit, a voltage regulator and a charging controller. When the power supply device and the charging module are connected with each other, the power converting unit of the charging module is in the backward direction and uses the electric power of the battery module to pre-charge a bus capacitor. If the voltage of the bus capacitor is higher than or equal to a first threshold value because of pre-charge, the voltage of an adjusting terminal of the charging module is adjusted. Consequently, the charging system is in a normal working mode.

Abstract: A multi-stage power converter includes a first-stage power conversion circuit, a second-stage power conversion circuit, a second-stage analogic sampler, a pulse width modulator, a first isolator, a pulse width analyzer and a control unit. The second-stage analogic sampler samples power parameter from the second-stage power conversion circuit. The pulse width modulator converts the power parameter into a pulse width modulation signal. The pulse width analyzer receives the pulse width modulation signal through the first isolator in an isolation manner, calculates a duty ratio of the pulse width modulation signal according to a rising edge and a falling edge of the pulse width modulation signal, and calculates the power parameter according to the duty ratio. The control unit controls operations of the second-stage power conversion circuit according to the power parameter that is obtained by the pulse width analyzer.