Abstract: Embodiments of the present application provide a pre-charging method of a power conversion device and a power conversion device. The power conversion device is used for a power conversion between a charging pile and a power battery and the method includes: receiving, by the power conversion device, a first message transmitted by a battery management system of the power battery, where the first message is used to indicate a charging readiness of the battery management system; and forwarding, by the power conversion device, the first message to the charging pile and performing a pre-charging, where the pre-charging includes charging a capacitor in the power conversion device. The technical solution in embodiments of the present application is capable of ensuring normal performing of a charging process.

Abstract: The present application provide a power supply control method for a power conversion apparatus, where the power conversion apparatus is configured to conduct a power conversion between a charging apparatus and a power battery, the method includes: conducting a power-on self-test with the charging apparatus of auxiliary power by the power conversion apparatus; determining a power supply priority order of the charging power and the power battery on the basis of a state parameter of the power battery under the condition that the self-test of the power conversion apparatus succeeds; determining the one of the charging power of the charging apparatus and the power battery with a higher power supply priority as a current working power of the power conversion apparatus by the power conversion apparatus. The method of the present application can provide a stable working power for the power conversion apparatus without additional power supply device.

Abstract: A charging method is provided, which includes: acquiring a state parameter of a traction battery, the state parameter including a battery temperature; sending first charging mode demand information to a charging pile when the battery temperature is lower than a first preset threshold, where the first charging mode demand information is used for indicating a pulse charging mode, the pulse charging mode is a charging mode using a pulsed voltage or a pulsed current, and the pulsed voltage or the pulsed current is used for charging the traction battery. According to the technical solution of the embodiment of the application, the charging pile can output pulse current to charge the traction battery, so as to prevent the performance of the traction battery from being affected by directly charging the traction battery at a low temperature, thereby ensuring the performance of the traction battery.

Abstract: Embodiments of the present application provides a method for pre-charging a power conversion device and a power conversion device. The power conversion device is configured to perform power conversion between a charging pile and a traction battery, and the method includes: receiving, by the power conversion device, a first message sent by a battery management system of the traction battery, and the first message is configured to indicate that the battery management system is ready for charging; performing, by the power conversion device, a pre-charging, and the pre-charging includes: charging a capacitor in the power conversion device; and forwarding, by the power conversion device, the first message to the charging pile after the pre-charging is completed. The technical solution of the embodiments of the present application can ensure a normal charging process.