Electric automobile, charger thereof and charger control method

Abstract

The invention discloses an electric vehicle, a charger thereof, and a charger control method. The charger comprises: a pre-charging switch; a pre-charging resistor and a first pre-charging capacitor which are connected with the pre-charging switch; an alternating current switch; an alternating current module connected with the alternating current switch, the pre-charging resistor and the first pre-charging capacitor; a second pre-charging capacitor connected with the alternating current module in parallel; a high-voltage direct-current module connected with the second pre-charging capacitor inparallel and connected with a high-voltage battery pack; and a controller used for controlling the high-voltage direct-current module to pre-charge the second pre-charging capacitor, closing the pre-charging switch to charge the first pre-charging capacitor through a power grid after the voltage of the second pre-charging capacitor is greater than a first preset threshold value and less than a second preset threshold value, and closing the alternating-current switch after the first pre-charging capacitor finishes pre-charging. Therefore, the pre-charging time can be greatly shortened, so thata relatively large current is effectively prevented from being generated when a relay is attracted, the relay is prevented from being sintered, and the reliability of the system is improved.

Description

technical field [0001] The invention relates to the technical field of electric vehicles, in particular to a charger for an electric vehicle, an electric vehicle and a charger control method for the electric vehicle. Background technique [0002] With the progress of commercialization of electric vehicles, DC converters and OBC on-board chargers in electric vehicles have gradually become important components in electric vehicles. In the charging system of electric vehicles, the DC converter and the OBC on-board charger can be integrated in a topology, and the pre-charging of the first pre-charging capacitor and the second pre-charging capacitor in the charging system is a system design an essential part of the. [0003] In related technologies, the grid is generally used to precharge the first precharging capacitor and the second precharging capacitor through a precharging resistor. However, when precharging in the above way, the required precharging time is longer, result...

AI Technical Summary

Problems solved by technology

However, when precharging in the above way, the required precharging time is longer, resulting in severe heating of the precharging resistor, and the resistance becomes larger, so that the voltage division of the precharging resistor is larger. Therefore, in the system and the precharging A relay connected in parallel with resistors tends to generate a large current when it is pulled in, which in turn leads to sintering of the relay, which greatly affects the reliability of the system

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